@article { ISI:000230685200006, title = {Biphenyl hydrogenation over supported transition metal catalysts under supercritical carbon dioxide solvent}, journal = {Applied Catalysis A - General}, volume = {288}, number = {1-2}, year = {2005}, month = {JUL}, pages = {43-47}, publisher = {ELSEVIER SCIENCE BV}, type = {Article}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

Catalytic hydrogenation of biphenyl to bicyclohexyl, an organic hydrogen storage medium, was examined over supported transition metal catalysts in supercritical carbon dioxide solvent. The yield of bicyclohexyl was almost 100\% over the charcoal-supported rhodium (Rh/C) and ruthenium (Ru/C) catalysts at the temperature of 323 K, which was much lower than that required for biphenyl hydrogenation in organic solvents (573 K). The initial activity was higher over the Rh/C catalyst, while the initial selectivity to bicyclohexyl was higher over the Ru/C catalyst. The conversion of biphenyl increased with increase in hydrogen and carbon dioxide pressures, while the selectivity to bicyclohexyl was independent of hydrogen and carbon dioxide pressures over both catalysts. (c) 2005 Elsevier B.V. All rights reserved.

}, keywords = {bicyclohexyl, biphenyl, charcoal-supported rhodium catalyst, charcoal-supported ruthenium catalyst, Hydrogen storage, Hydrogenation, Supercritical carbon dioxide}, issn = {0926-860X}, doi = {10.1016/j.apcata.2005.04.021}, author = {Hiyoshi, Norihito and Rode, C. V. and Sato, O. and Shirai, M.} } @article { ISI:000233927900005, title = {Synthesis, characterization and catalytic application of Ru-II-ethylenediamine complex - mesoporous silica as heterogeneous catalyst system in chemo-selective hydrogenation of alpha,beta-unsaturated carbonyl compounds}, journal = {Microporous and Mesoporous Materials}, volume = {87}, number = {1}, year = {2005}, month = {DEC}, pages = {33-44}, publisher = {ELSEVIER SCIENCE BV}, type = {Article}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

An efficient heterogeneous catalyst system for chemo-selective hydrogenation of alpha,beta-unsaturated aldehydes was synthesized, involving anchoring of a Ru-II-phosphine complex on the inner surfaces of organo-functionalized (propylamine and propylethylenediamine) mesoporous MCM-41 and MCM-48 materials. Powder XRD, SEM and TEM experiments reveal highly ordered hexagonal and cubic patterns of the organically modified MCM-41 and MCM-48 materials, respectively, even after incorporation of Ru complexes. Moreover, the integrity of the Ru complex was retained after anchoring into the mesoporous hosts, which was supported by FTIR, P-31 CP MAS NMR and XPS analyses. This heterogeneous catalyst shows promising activity and chemo-selectivity towards hydrogenation of carbonyl groups in alpha,beta-unsaturated aldehydes. The effects of reaction temperature, reaction time and hydrogen pressure on the activity and selectivity were studied in detail. The anchored solid catalysts can be recycled effectively and reused several times without any loss in activity and selectivity. Although, the initial activity of the same Ru complex when grafted onto the organically modified surfaces of fumed silica is comparable to corresponding MCM41/MCM-48 catalysts, the activity and chemo-selectivity significantly decrease during recycle of the catalyst due to leaching. (c) 2005 Elsevier Inc. All rights reserved.

}, keywords = {chemo-selective, heterogeneous catalysis, Heterogenization, Hydrogenation, mesoporous materials, organo-functionalization, Ru-II-ethylenediamine complex, unsaturated aldehyde}, issn = {1387-1811}, doi = {10.1016/j.micromeso.2005.06.042}, author = {Ghosh, Anirban and Kumar, R} } @article { ISI:000239179300033, title = {Enantioselective synthesis of (+)-(S,S)-reboxetine}, journal = {Synlett}, number = {11}, year = {2006}, month = {JUL}, pages = {1771-1773}, publisher = {GEORG THIEME VERLAG KG}, type = {Article}, address = {RUDIGERSTR 14, D-70469 STUTTGART, GERMANY}, abstract = {

An efficient enantioselective synthesis leading directly to (+)-(S,S)-reboxetine has been described from commercially available trans-cinnammyl bromide using Sharpless asymmetric dihydroxylation as the key step.

}, keywords = {coupling, Dihydroxylation, Hydrogenation, reboxetine, trans-cinnamyl bromide}, issn = {0936-5214}, doi = {10.1055/s-2006-944210}, author = {Siddiqui, Shafi A. and Narkhede, Umesh C. and Lahoti, Rajgopal J. and Srinivasan, Kumar V.} } @article { ISI:000239869200024, title = {Low temperature hydrogenation of tetralin over supported rhodium catalysts in supercritical carbon dioxide solvent}, journal = {Applied Catalysis A-General}, volume = {310}, year = {2006}, month = {AUG}, pages = {194-198}, publisher = {ELSEVIER SCIENCE BV}, type = {Article}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

Hydrogenation of tetralin was studied over supported rhodium catalysts in supercritical carbon dioxide solvent at 333 K. The results were compared with those in an organic solvent and under neat conditions. Higher cis-decalin yield was obtained in supercritical carbon dioxide solvent than under non-supercritical conditions. It was observed that higher hydrogen concentration at the surface in supercritical carbon dioxide solvent led to fast direct hydrogenation of tetralin to cis-decalin; the flipping of the intermediate, octalin, to give trans-decalin could be prevented. (C) 2006 Elsevier B.V. All rights reserved.

}, keywords = {cis-decalin, Hydrogen storage, Hydrogenation, Supercritical carbon dioxide, supported rhodium catalysts, tetralin}, issn = {0926-860X}, doi = {10.1016/j.apcata.2006.05.040}, author = {Hiyoshi, Norihito and Mine, Eiichi and Rode, Chandrashekhar V. and Sato, Osamu and Shirai, Masayuki} } @article { ISI:000238416100033, title = {Ring hydrogenation of naphthalene and 1-naphthol over supported metal catalysts in supercritical carbon dioxide solvent}, journal = {Catalysis Today}, volume = {115}, number = {1-4}, year = {2006}, note = {8th International Conference on Carbon Dioxide Utilization, Univ Oslo, Oslo, NORWAY, JUN 20-23, 2005}, month = {JUN}, pages = {248-253}, publisher = {ELSEVIER SCIENCE BV}, type = {Article}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

Catalytic ring hydrogenations of naphthalene and 1-naphthol were studied over several supported metal catalysts in supercritical carbon dioxide solvent at low temperature. Higher concentration of hydrogen in supercritical carbon dioxide and lower reaction temperature were responsible for higher catalyst activity and selectivities to the desired partial ring hydrogenated products as compared with those observed in organic solvent for the same catalyst. (c) 2006 Elsevier B.V. All rights reserved.

}, keywords = {1-naphthol, Hydrogenation, Naphthalene, Supercritical carbon dioxide, supported metal catalyst}, issn = {0920-5861}, doi = {10.1016/j.cattod.2006.02.048}, author = {Shirai, M. and Rode, C. V. and Mine, Eiichi and Sasaki, A. and Sato, O. and Hiyoshi, Norihito} } @article { ISI:000252252400015, title = {Highly chemoselective catalytic system for hydrogenation of diketones to ketols: an environmentally benevolent system}, journal = {Catalysis Letters}, volume = {120}, number = {3-4}, year = {2008}, month = {JAN}, pages = {257-260}, publisher = {SPRINGER}, type = {Article}, address = {233 SPRING STREET, NEW YORK, NY 10013 USA}, abstract = {

Ru(Phen)(2)Cl-2 [Phen = Phenanthroline] anchored in organo-functionalized MCM-41 [Ru(Phen)(2)Cl-NH-MCM-41] efficiently catalyzes highly chemoselective hydrogenation of diketones to ketols (Sel. similar to 99\%) under environmentally benign tri-phasic (solid-liquid-liquid) reaction condition in aqueous medium.

}, keywords = {Chemoselective, dione, Hydrogenation, ketol, ruthenium phenanthroline, Water}, issn = {1011-372X}, doi = {10.1007/s10562-007-9278-3}, author = {Deshmukh, Amit A. and Kinage, Anil K. and Kumar, Rajiv} } @article { ISI:000260452200009, title = {[Ru(salen)(NO)] complex encapsulated in mesoporous SBA-16 as catalyst for hydrogenation of ketones}, journal = {Catalysis Communications}, volume = {10}, number = {1}, year = {2008}, month = {OCT}, pages = {45-48}, publisher = {ELSEVIER SCIENCE BV}, type = {Article}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

SBA-16 mesoporous silica with cubic lm3m structure was synthesized using Pluronic F127 poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) triblock copolymer (EO106PO70EO106) and it blends with Pluronic P123 triblock copolymer (EO20PO70EO20) as supramolecular templates. The resulting material was used for encapsulating [Ru(salen)(NO)] complex and used in the hydrogenation of ketones to the corresponding alcohols. The pore entrance size of SBA-16 was precisely tailored by silylation with diphenyldichlorosilane to trap [Ru(salen)(NO)] complex in the cage of SBA-16. Small angle XRD, N-2 sorption measurements, UV-Vis and FT-IR analysis evidences the structural integrity of mesoporous silica as well as the complex. (C) 2008 Elsevier B.V. All rights reserved.

}, keywords = {Encapsulation, Hydrogenation, Ketones, SBA-16, [Ru(salen)(NO)] complex}, issn = {1566-7367}, doi = {10.1016/j.catcom.2008.07.029}, author = {Bordoloi, Ankur and Amrute, Amol P. and Halligudi, Shivaraj B.} } @article { ISI:000283589900009, title = {Chemoselective hydrogenation of cinnamaldehyde over Pd/CeO2-ZrO2 catalysts}, journal = {Catalysis Letters}, volume = {140}, number = {1-2}, year = {2010}, month = {NOV}, pages = {55-64}, publisher = {SPRINGER}, address = {233 SPRING ST, NEW YORK, NY 10013 USA}, abstract = {

Selective hydrogenation of cinnamaldehyde over Pd (2 wt\%) supported on CeO2, ZrO2 and CeO2-ZrO2 catalysts is reported for the first time. In general, the olefinic (C=C) group of cinnamaldehyde is preferentially hydrogenated compared to the carbonyl (C=O) group. This selectivity preference could, however, be altered or reversed by adding alkali additives to the catalyst. The influence of additive on the structure and redox properties of the active sites and correlation of that with selective hydrogenation activity is investigated.

}, keywords = {alpha, beta-Unsaturated aldehyde, Ceria-zirconia, Cinnamaldehyde, Hydrogenation, palladium catalyst}, issn = {1011-372X}, doi = {10.1007/s10562-010-0423-z}, author = {Bhogeswararao, Seemala and Srinivas, D.} } @article { ISI:000284052600021, title = {Covalently immobilized triphenylphosphine rhodium complex: synthesis, characterization, and application in catalytic olefin hydrogenation}, journal = {Chemcatchem}, volume = {2}, number = {11}, year = {2010}, month = {NOV}, pages = {1477-1482}, publisher = {WILEY-BLACKWELL}, address = {COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA}, abstract = {

A trimethoxysilane functionalized triphenylphosphine was coordinated to rhodium(I) and the resulting rhodium complex was covalently bound to a mesoporous SBA-15 support. The catalytic activity of this hybrid material was studied for the hydrogenation of 2-cyclohexen-1-one and compared with the corresponding homogeneous catalyst. According to the (31)P-MAS NMR data, the catalytically active species was stable against oxidation; no structural change could be detected after exposing it to air for more than two months. Transmission electron microscopy (TEM) measurements on the used catalyst confirmed that the rhodium species was also stable against reduction to the metal because the formation of rhodium nanoparticles during the catalysis could be excluded. The kinetic curves of the recycled system confirmed that this hybrid catalyst shows excellent activity, selectivity, stability, and reusability, and is truly heterogeneous in the hydrogenation reaction.

}, keywords = {alkenes, heterogeneous catalysis, Hydrogenation, mesoporous materials, Rhodium}, issn = {1867-3880}, doi = {10.1002/cctc.201000133}, author = {Wang, Lei and Jia, Mingjun and Shylesh, Sankaranarayanapillai and Philippi, Thomas and Seifert, Andreas and Ernst, Stefan and Singh, Anand Pal and Thiel, Werner R.} } @article { ISI:000285772600015, title = {Heterogenized Ru(II) phenanthroline complex for chemoselective hydrogenation of diketones under biphasic aqueous medium}, journal = {Journal of Molecular Catalysis A-Chemical}, volume = {333}, number = {1-2}, year = {2010}, month = {DEC}, pages = {114-120}, publisher = {ELSEVIER SCIENCE BV}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

The chemoselective hydrogenation of acetylacetone to 4-hydroxypentan-2-one over immobilized ruthenium phenanthroline metal complexes in amino functionalized MCM-41 in biphasic aqueous reaction medium was investigated. The catalyst was characterized by XRD, TEM, surface analysis, FT-IR and UV-vis to understand the morphology, complex geometry, and XPS such that the oxidation state of the metal complex inside the MCM-41 framework could be understood. The use of water as a solvent, not only gives high activity and selectivity for hydrogenation of acetylacetone, but also gives a path for an environmentally safer process. The optimizations of ligand, metal to ligand ratio, the choice of solvent and other reaction parameters were studied in detail. The heterogeneous catalytic system gave a higher degree of chemoselectivity (99\%) towards 4-hydroxypentan-2-one as compared to homogeneous catalyst when hydrogenation was carried out using water as a solvent. The immobilized ruthenium-phenanthroline complex was easily separated and reused. (C) 2010 Elsevier B.V. All rights reserved.

}, keywords = {4-Hydroxypentan-2-one, acetylacetone, Chemoselective, Diketone, Hydrogenation, Phenanthroline, ruthenium, Water}, issn = {1381-1169}, doi = {10.1016/j.molcata.2010.10.005}, author = {Deshmukh, Amit A. and Kinage, Anil K. and Kumar, Rajiv and Meijboom, Reinout} } @article { ISI:000274292700015, title = {Polymer-supported palladium-imidazole complex catalyst for hydrogenation of substituted benzylideneanilines}, journal = {Journal of Molecular Catalysis A-Chemical}, volume = {317}, number = {1-2}, year = {2010}, month = {FEB}, pages = {111-117}, publisher = {ELSEVIER SCIENCE BV}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

The polymer-supported palladium-imidazole complex catalyst was synthesized and characterized by various techniques Such as elemental analysis, IR spectroscopy and TG analysis. The physico-chemical properties such as bulk density, Surface studies by BET method and swelling studies of catalyst in different solvents were investigated. XPS Studies were carried out to identify the oxidation state of palladium in the catalyst. The morphology of the support and the catalyst was studied using scanning electron microscope. Using the synthesized catalyst, hydrogenation of benzylideneaniline and a few of its para Substituted derivatives was carried out at ambient conditions. The influence of variation in temperature, concentration of the catalyst as well as the substrate on the rate of reaction Was Studied. The catalyst showed an excellent recycling efficiency over six cycles without leaching of metal from the polymer support. (C) 2009 Elsevier B.V. All rights reserved.

}, keywords = {Benzylideneaniline, Hydrogenation, kinetics, Polymer-supported palladium-imidazole complex catalyst}, issn = {1381-1169}, doi = {10.1016/j.molcata.2009.10.030}, author = {Udayakumar, V. and Alexander, S. and Gayathri, V. and Shivakumaraiah and Patil, K. R. and Viswanathan, B.} } @article { ISI:000281783500005, title = {Short and efficient synthesis of (S)-(+)-2-(Hydroxymethyl)-6-piperidin-2-one}, journal = {Synthesis-Stuttgart}, number = {15}, year = {2010}, month = {AUG}, pages = {2512-2514}, publisher = {GEORG THIEME VERLAG KG}, address = {RUDIGERSTR 14, D-70469 STUTTGART, GERMANY}, abstract = {

A concise synthesis of (S)-(+)-2-(hydroxymethyl)-6-piperidin-2-one is described that employs L-aspartic acid as chiral pool starting material and Wittig reaction as the key step.

}, keywords = {Amino acid, Hydrogenation, L-aspartic acid, pipecolate, piperidone, Wittig reaction}, issn = {0039-7881}, doi = {10.1055/s-0029-1218823}, author = {Upadhyay, Puspesh K. and Kumar, Pradeep} } @article { ISI:000288141700012, title = {Synthesis, characterisation of polymer-supported palladium-2-methylimidazole complex catalyst for the hydrogenation of aromatic nitro compounds}, journal = {Journal of Chemical Research}, number = {2}, year = {2011}, month = {FEB}, pages = {112-115}, publisher = {SCIENCE REVIEWS 2000 LTD}, address = {PO BOX 314, ST ALBANS AL1 4ZG, HERTS, ENGLAND}, abstract = {

A polymer-supported palladium-2-methylimidazole complex was synthesised and characterised by various physicochemical methods. The complex was successfully used as a catalyst for the hydrogenation of nitrobenzene and a few of its derivatives under ambient conditions. Results reveal that the electronic as well as the steric effects of the substitutent control the rate of hydrogenation of the nitro group in the studied nitro compounds. The kinetics of hydrogenation and the reusability of the catalyst were also studied.

}, keywords = {aromatic nitro compounds, Hydrogenation, polymer-supported complex catalyst, transition metal complexes}, issn = {1747-5198}, doi = {10.3184/174751911X556855}, author = {Velua, Udayakumar and Stanislaus, Alexander and Virupaiah, Gayathri and Shivakumaraiah and Patil, Kashinath Rangu and Balasubramanian, Viswanathan} } @article { ISI:000306771600005, title = {Covalently anchored ruthenium-phosphine complex on mesoporous organosilica: catalytic applications in hydrogenation reactions}, journal = {Catalysis Communications}, volume = {25}, year = {2012}, month = {AUG}, pages = {22-27}, publisher = {ELSEVIER SCIENCE BV}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

New heterogeneous catalysts for alkene hydrogenation reactions were prepared by the immobilization of trimethoxysilane functionalized triphenylphosphine eta(6)-p-cymene ruthenium complex on mesoporous organosilica (PMO-Ru). Characterization techniques confirmed the structural integrity of the organosilica material and proved the successful anchoring of ruthenium complex. Catalytic activity and stability of PMO-Ru sample investigated in the hydrogenation of various olefins showed higher activity than a neat and MCM-41 supported ruthenium catalyst. High catalytic activity and stability of organosilica supported ruthenium catalyst are attributed to the hydrophobic environments and to the unique structural features imparted from the presence of organic groups in the framewall positions. (C) 2012 Elsevier B.V. All rights reserved.

}, keywords = {Heterogenization, Hydrogenation, Organosilica, ruthenium, Triphenyl phosphine}, issn = {1566-7367}, doi = {10.1016/j.catcom.2012.04.002}, author = {Sisodiya, Sheetal and Lazar, Anish and Shylesh, Sankaranarayanapillai and Wang, Lei and Thiel, Werner R. and Singh, Anand Pal} } @article { ISI:000300074300005, title = {Intramolecular selective hydrogenation of cinnamaldehyde over CeO2-ZrO2-supported Pt catalysts}, journal = {Journal of Catalysis}, volume = {285}, number = {1}, year = {2012}, month = {JAN}, pages = {31-40}, publisher = {ACADEMIC PRESS INC ELSEVIER SCIENCE}, address = {525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA}, abstract = {

Selective liquid phase hydrogenation of cinnamaldehyde is reported, for the first time, over CeO2, ZrO2, and CeO2-ZrO2-supported Pt catalysts. Cinnamyl alcohol is the selective product. These catalysts are highly active and selective even at 25 degrees C and found to be superior to most of the hitherto known supported Pt catalysts. Alkali addition (NaOH) has enhanced the performance of these catalysts. At an optimized reaction condition, 95.8\% conversion of cinnamaldehyde and 93.4\% selectivity of cinnamyl alcohol have been obtained. Acidity of the support (due to the presence of ZrO2 component) and higher electron density at Pt (due to CeO2 component) are attributed to be responsible for the superior catalytic activity of Pt supported on CeO2-ZrO2 composite material. (C) 2011 Elsevier Inc. All rights reserved.

}, keywords = {alpha, beta-Unsaturated aldehyde, Ceria-zirconia, Cinnamaldehyde, Hydrogenation, Promotion by alkali ions, Supported Pt catalyst}, issn = {0021-9517}, doi = {10.1016/j.jcat.2011.09.006}, author = {Bhogeswararao, Seemala and Srinivas, D.} } @article { ISI:000305033900088, title = {Kinetics of hydrogenation of lauric acid in a batch slurry reactor using Ru-Sn/TiO2 catalyst}, journal = {Asian Journal of Chemistry}, volume = {24}, number = {6}, year = {2012}, month = {JUN}, pages = {2767-2771}, publisher = {ASIAN JOURNAL OF CHEMISTRY}, address = {11/100 RAJENDRA NAGAR, SECTOR 3,, SAHIBABAD 201 005, GHAZIABAD, INDIA}, abstract = {

Ru-Sn catalyst was prepared in-house by impregnation method. This catalyst was found to be stable for four recycles. The rate of hydrogenation of lauric acid (LAC) using Ru-Sn/TiO2 catalyst was found to be linearly dependent on catalyst loading, lauric acid concentration old hydrogen partial pressure. The rate data obtained from kinetic study were fitted to simple rate equation based on Langmuir-Hinshelwood (L-H) type model. Based on kinetic data the hydrogenation of lauric acid over Ru-Sn/TiO2 catalyst is proposed to occur by I dual site mechanism the activation energy for hydrogenation of lauric acid to lauryl alcohol (LAOH) using Rii-Sn/TiO2 catalyst was found to be 77.2 kJ/mol.

}, keywords = {Hydrogenation, kinetics, Langmuir-Hinshelwood model, Ru-Sn/TiO2 catalyst}, issn = {0970-7077}, author = {Shinde, S. B. and Deshpande, R. M.} } @article { ISI:000309370500010, title = {Reactions in supercritical carbon dioxide}, journal = {Indian Journal of Chemistry Section A-Inorganic Bio-Inorganic Physical Theoretical \& Analytical Chemistry}, volume = {51}, number = {9-10, SI}, year = {2012}, month = {SEP}, pages = {1298-1305}, publisher = {NATL INST SCIENCE COMMUNICATION-NISCAIR}, address = {DR K S KRISHNAN MARG, PUSA CAMPUS, NEW DELHI 110 012, INDIA}, abstract = {

Use of conventional organic solvents often leads to the formation of hazardous waste, the disposal of which is a matter of environmental concern. Carbon dioxide is considered to be a green reaction medium and a good replacement for conventional organic solvents as it is benign and leads to elimination/reduction of hazardous wastes. Use of CO2 at near/above critical conditions has several additional advantages as the reactions can be pressure-tuned to eliminate transport resistance, increase solvent power and heat capacity. Hence, there has been considerable interest in the use of supercritical carbon dioxide as either a replacement of conventional organic solvent or as a co-solvent in reactions. Herein, recent developmenst in this area during the last decade is reviewed, specifically in gas-liquid (organic hydrogenation, hydroformylation and oxidation) and liquid-liquid (carbon-carbon coupling, alkylation, acetylation, esterification) reactions.

}, keywords = {Alkylation, Carbon dioxide, Hydroformylation, Hydrogenation, Oxidation, Supercritical carbon dioxide}, issn = {0376-4710}, author = {Mayadevi, S.} } @article { ISI:000304401600015, title = {Surface species of supported ruthenium catalysts in selective hydrogenation of levulinic esters for bio-refinery application}, journal = {Catalysis Letters}, volume = {142}, number = {6}, year = {2012}, month = {JUN}, pages = {779-787}, publisher = {SPRINGER}, address = {233 SPRING ST, NEW YORK, NY 10013 USA}, abstract = {

Several supported noble metal catalysts were screened for the hydrogenation of methyl levulinate to gamma-valerolactone (GVL). Among these catalysts 5 \% Ru/C showed the highest conversion of 95 \% of methyl levulinate with 91 \% selectivity to GVL. A detailed characterization was carried out using TPR, XRD, XPS and BET techniques. XPS studies revealed that higher extent of Ru-0 species in case of carbon supported Ru was responsible for its higher hydrogenation activity as compared to Ru on other supports. Effect of process parameters such as temperature, H-2 pressure, catalyst and substrate concentration and metal loading on methyl LA conversion and selectivity to GVL also has been studied. 5 \% Ru/C catalyst was found to be stable up to five reuses.

}, keywords = {5 \% Ru/C, Biofeedstock, gamma-Valerolactone, H-2-TPR, Hydrogenation, Methyl levulinate, XPS}, issn = {1011-372X}, doi = {10.1007/s10562-012-0822-4}, author = {Hengne, Amol M. and Biradar, Narayan S. and Rode, Chandrashekhar V.} } @article {CSIR, title = {Hydrogenation of polar bonds catalysed by ruthenium-pincer complexes}, journal = {Ruthenium in Catalysis}, volume = {48}, number = {5}, year = {2014}, note = {3rd International Conference on Advances in Computing, Communications and Informatics (ICACCI), New Delhi, INDIA, SEP 24-27, 2014}, month = {MAR}, pages = {19-43}, publisher = {IEEE Commun Soc; IEEE Syst Man \& Cybernet Soc; Galgotias Coll Engn \& Technol; Hochschule Offenburg Univ Appl Sci; Int Neural Network Soc; India Chapter \& Res Publishing Serv; Madhyam; WizIQ; ICACCI; IEEE}, address = {HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY}, abstract = {

Catalytic hydrogenation of polar bonds using molecular hydrogen is an important, atom-economical synthetic reaction. Classical reduction methods of polar bond often require reactive metal-hydride reagents in stoichiometric amount and produce copious waste. Hydrogenation of carbonyl compounds in particular provides {\textquoteleft}green{\textquoteright} approaches to synthetically important building blocks, such as alcohols and amines. We have designed and synthesized several ruthenium-based pincer catalysts for unprecedented hydrogenation reactions including: (1) amides to alcohols and amines, (2) biomass-derived di-esters to 1,2-diols and (3) CO2 and CO derivatives to methanol. These atom-economical reactions operate under neutral, homogeneous conditions, at mild temperatures, mild hydrogen pressures, and can operate in absence of solvent with no generation of waste. The postulated mechanisms involve metal-ligand cooperation (MLC) by aromatization-dearomatization of the heteroaromatic pincer core.

}, keywords = {Amides, Carbon dioxide, Esters, Hydrogen, Hydrogenation, Metal-ligand cooperation, Pincer complexes, ruthenium}, isbn = {978-3-319-08482-4; 978-3-319-08481-7}, issn = {1436-6002}, doi = {10.1007/3418_2014_77}, author = {Balaraman, Ekambaram and Milstein, David}, editor = {Bruneau, C. and Dixneuf, P. H.} } @article {45975, title = {Palladium nanoparticles supported on magnesium hydroxide fluorides: a selective catalyst for olefin hydrogenation}, journal = {ChemCatChem}, volume = {6}, year = {2014}, month = {NOV}, pages = {3182-3191}, type = {Article}, abstract = {

A one-pot synthesis of palladium nanoparticles supported on magnesium hydroxide fluoride has been performed with the fluorolytic sol-gel method. The prepared catalysts were characterized by using various physicochemical techniques. The sol-gel method led to high surface area (\>135 m(2)g(-1)), mesoporous catalysts (pore volume=0.19-0.23 cm(3)g(-1), pore diameter=3-5 nm) with uniformly dispersed palladium nanoparticles approximately 2 nm in diameter on the surface. The catalysts synthesized by using different concentrations of aqueous hydrofluoric acid exhibited changing surface and acidic properties. Very high dispersion of palladium on magnesium fluoride (47\%) was obtained with 1 wt\% palladium loading. The catalysts were used for hydrogenation of various olefins in the presence of other organic functionalities at room temperature and atmospheric hydrogen pressure. Various substituted olefins were hydrogenated with almost 100\% conversion and selectivity. The catalysts were recycled efficiently over five cycles without appreciable loss in catalytic activity. There was no palladium leaching under the reaction conditions, which was confirmed by inductively coupled plasma atomic emission spectroscopy analysis. Activation of olefin on the catalyst surface could not be observed by in situ FTIR studies, indicating facile activation of hydrogen on the palladium supported on magnesium hydroxide fluoride.

}, keywords = {alkenes, heterogeneous catalysis, Hydrogenation, magnesium fluorides, Palladium}, issn = {1867-3880}, doi = {10.1002/cctc.201402469}, author = {Acham, Vaibhav R. and Biradar, Ankush V. and Dongare, Mohan K. and Kemnitz, Erhard and Umbarkar, Shubhangi B.} } @article { ISI:000330812400022, title = {Single-pot formation of THFAL via catalytic hydrogenation of FFR over Pd/MFI catalyst}, journal = {ACS Sustainable Chemistry \& Engineering}, volume = {2}, number = {2}, year = {2014}, month = {FEB}, pages = {272-281}, publisher = {AMER CHEMICAL SOC}, address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA}, abstract = {

Furfural (FFR) was selectively hydrogenated in a single pot to tetrahydrofurfuryl alcohol (THFAL) over a Si MFI molecular sieve supported Pd catalyst. Studies on catalyst screening revealed that both the metal function and the support were critical for directing the selectivity to the ringhydrogenated product, THFAL. The structural feature of MFI as shown by XRD was completely retained in the used sample of the 3\% Pd/MFI catalyst confirming its stability under reaction conditions. XRD, along with SEM characterization of the used samples, established retention of morphology of the structured silicate, suggesting a strong interaction between hexagonal porous silicate and Pd particles. The complete conversion of FFR with an enhanced selectivity of 95\% to THFAL could be achieved by recycling the crude of the first hydrogenation experiment over the same 3\% Pd/MFI catalyst.

}, keywords = {Biomass conversion, Hydrogenation, Pd/MFI, Recyclability, THFAL}, issn = {2168-0485}, doi = {10.1021/sc400302b}, author = {Biradar, Narayan S. and Hengne, Amol M. and Birajdar, Shobha N. and Niphadkar, Prashant S. and Joshi, Praphulla N. and Rode, Chandrashekhar V.} } @article { ISI:000337551800010, title = {Solid base supported metal catalysts for the oxidation and hydrogenation of sugars}, journal = {Journal of Molecular Catalysis A-Chemical}, volume = {388}, number = {SI}, year = {2014}, month = {JUL}, pages = {90-99}, publisher = {ELSEVIER SCIENCE BV}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

Pt impregnated on gamma-Al2O3 (acidic support) and hydrotalcite (basic support) catalysts were synthesized, characterized and used in the oxidation and hydrogenation reactions of C5 and C6 sugars. In the absence of homogeneous base, 83\% yield for gluconic acid; an oxidation product of glucose can be achieved over Pt/hydrotalcite (HT) catalyst at 50 degrees C under atmospheric oxygen pressure. Similarly, 57\% yield for xylonic acid, an oxidation product of xylose is also possible over Pt/HT catalyst. Hydrogenation of glucose conducted using Pt/gamma-Al2O3 + HT catalytic system showed 68\% sugar alcohols (sorbitol + mannitol) formation. The 82\% yield for C5 sugar alcohols (xylitol + arabitol) was obtained by subjecting xylose to hydrogenation over Pt/gamma-Al2O3 + HT at 60 degrees C. UV analysis helped to establish the fact that under alkaline conditions sugars prefer to remain in open chain form in the solution and thus exposes -CHO group which further undergoes oxidation and hydrogenation reactions to yield acids and alcohols. (c) 2013 Elsevier B.V. All rights reserved.

}, keywords = {Hydrogenation, Oxidation, Solid base, Sugars, Supported metal catalysts}, issn = {1381-1169}, doi = {10.1016/j.molcata.2013.09.014}, author = {Tathod, Anup and Kane, Tanushree and Sanil, E. S. and Dhepe, Paresh Laxmikant} } @article { ISI:000356739400008, title = {Catalytic conversion of furfural to industrial chemicals over supported Pt and Pd catalysts}, journal = {Journal of Catalysis}, volume = {327}, year = {2015}, month = {JUL}, pages = {65-77}, publisher = {ACADEMIC PRESS INC ELSEVIER SCIENCE}, address = {525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA}, abstract = {

Several industrial chemicals were prepared by hydrogenation of furfural over gamma-Al2O3-supported Pt and Pd catalysts. These catalysts were active even at room temperature (25 degrees C). While the Pt catalysts were selective for C=O hydrogenation (yielding furfuryl alcohol), Pd facilitated ring hydrogenation (producing tetrahydrofurfuryl alcohol). At high temperature (240 degrees C), the Pd catalyst exhibited excellent decarbonylation activity forming furan with 85\% yield. The catalyst was reusable even in the absence of external hydrogen. The presence of hydrogen led to ring-opened products. Furan was quantitatively converted at 25 degrees C to tetrahydrofuran. Acidity of the support made a marked influence on the activity and selectivity. Pt on SO4-ZrO2 favored hydrogenolysis yielding 2-methyl furan along with furan with \>75 wt\% selectivity. Particle size, metal dispersion, and solvent influenced catalytic activity. Differences in structure and mode of furfural adsorption were also the causes for variations in selectivity of these supported Pt and Pd catalysts. (C) 2015 Elsevier Inc. All rights reserved.

}, keywords = {Biomass to fuels and chemicals, Decarbonylation, furfural, Hydrogenation, Hydrogenolysis, Supported Pt and Pd catalysts}, issn = {0021-9517}, doi = {10.1016/j.jcat.2015.04.018}, author = {Bhogeswararao, Seemala and Srinivas, D.} } @article { ISI:000347150700005, title = {Efficient method for the conversion of agricultural waste into sugar alcohols over supported bimetallic catalysts}, journal = {Bioresource Technology}, volume = {178}, year = {2015}, month = {FEB}, pages = {36-44}, publisher = {ELSEVIER SCI LTD}, address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND}, abstract = {

Promoter effect of Sn in the PtSn/gamma-Al2O3 (AL) and PtSn/C bimetallic catalysts is studied for the conversion of variety of substrates such as, C5 sugars (xylose, arabinose), C6 sugars (glucose, fructose, galactose), hemicelluloses (xylan, arabinogalactan), inulin and agricultural wastes (bagasse, rice husk, wheat straw) into sugar alcohols (sorbitol, mannitol, xylitol, arabitol, galactitol). In all the reactions, PtSn/AL showed enhanced yields of sugar alcohols by 1.5-3 times than Pt/AL. Compared to C, AL supported bimetallic catalysts showed prominent enhancement in the yields of sugar alcohols. Bimetallic catalysts characterized by X-ray diffraction study revealed the stability of catalyst and absence of alloy formation thereby indicating that Pt and Sn are present as individual particles in PtSn/AL. The TEM analysis also confirmed stability of the catalysts and XPS study disclosed formation of electron deficient Sn species which helps in polarizing carbonyl bond to achieve enhanced hydrogenation activity. (C) 2014 Elsevier Ltd. All rights reserved.

}, keywords = {Agricultural waste, Bimetallic catalyst, Hydrogenation, Monosaccharides, Polysaccharides}, issn = {0960-8524}, doi = {10.1016/j.biortech.2014.10.036}, author = {Tathod, Anup P. and Dhepe, Paresh Laxmikant} } @article { ISI:000374626200020, title = {Role of surface synergistic effect on the performance of Ni-based hydrotalcite catalyst for highly efficient hydrogenation of furfural}, journal = {Journal of Molecular Catalysis A-Chemical}, volume = {417}, year = {2016}, month = {JUN}, pages = {153-162}, publisher = {ELSEVIER SCIENCE BV}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

The selective vapor phase hydrogenation of furfural at ambient pressure has been investigated using a facile and robust hydrotalcite derived Ni containing mixed oxide catalyst. The systematic characterization results conferred that the difficulty in the reduction of Ni species due to the strong interaction between Ni and support, which facilitated from the homogeneous distribution of hydrotalcite structure. It was also found that the structure and catalytic performance of the catalysts were greatly influenced by Ni loading. Through fine-tuned surface elemental sites and reaction conditions, furfural conversion of 98\% with 95\% of furfuryl alcohol selectivity was achieved over a MAN-2 catalyst containing two molar ratio of Ni. The results have demonstrated that the incorporation of Mg significantly enhances the Ni-support interaction, Ni dispersion and catalytic performance. The high efficiency of the Ni-based hydrotalcite derived catalyst was mainly attributed to the surface synergistic interaction between the catalytically active metallic Ni sites and the strong basic sites, which furnished an eco-benign and sustainable catalyst for the selective hydrogenation of furfural. Furthermore, the spent catalyst analysis substantiated that no significant difference in the catalyst phase was observed even after 48 h of reaction stream. (C) 2016 Elsevier B.V. All rights reserved.

}, keywords = {alcohol-hydrotalcites-selective, Biomass-frurfural-furfuryl, Hydrogenation}, issn = {1381-1169}, doi = {10.1016/j.molcata.2016.03.019}, author = {Manikandan, Marimuthu and Venugopal, Ashok Kumar and Prabu, Kandasamy and Jha, Ratnesh Kumar and Thirumalaiswamy, Raja} } @article { ISI:000381165300025, title = {Studies of synergy between metal-support interfaces and selective hydrogenation of HMF to DMF in water}, journal = {Journal of Catalysis}, volume = {340}, year = {2016}, month = {AUG}, pages = {248-260}, publisher = {ACADEMIC PRESS INC ELSEVIER SCIENCE}, address = {525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA}, abstract = {

Metal-support interfaces play a very important role in heterogeneous catalysis. The interfacial interactions not only are responsible for stabilizing the necessary oxidation state to facilitate the reaction but also enhance the stability of the catalyst system. Nano dispersion of Ni on mesoporous nitrogen-rich carbon material has been achieved using two different synthesis methods. It was observed that nickel (0) gets stabilized by strong interfacial interaction with the nitrogen atoms of the support material, and the material was found to be very economic and efficient for the conversion of HMF to DMF in aqueous medium. The material shows \>= 99\% conversion to 5-(hydroxymethyl) furfural (HMF) within 6 h of reaction with 98.7\% DMF selectivity. A unique correlation between synthesis methods and particle sizes with catalytic performance has been observed for these newly developed materials. Furthermore, a DFT calculation has been performed to predict the reaction mechanism. (C) 2016 Elsevier Inc. All rights reserved.

}, keywords = {biofuels, Biomass, Hydrogenation, mesoporous carbon, Ni-CNx}, issn = {0021-9517}, doi = {10.1016/j.jcat.2016.05.012}, author = {Goyal, Reena and Sarkar, Bipul and Bag, Arijit and Siddiqui, Nazia and Dumbre, Deepa K. and Lucas, Nishita and Bhargava, Suresh Kumar and Bordoloi, Ankur} } @article {44038, title = {Less frustration, more Activity{\textemdash}theoretical insights into frustrated lewis pairs for hydrogenation catalysis}, journal = {ChemCatChem}, volume = {9}, year = {2017}, month = {AUG}, pages = { 3013-3022}, type = {Journal Article}, abstract = {The field of frustrated Lewis pair (FLP) chemistry has seen rapid development in only a few years. FLPs have performed most spectacularly in hydrogenation catalysis: a wide variety of FLP-based systems can catalyze the hydrogenation of a range of different substrates, including imines, enamines, ketones, alkynes, and alkenes. However, FLP-based hydrogenation catalysts are yet to match the efficiency of their transition-metal counterparts. The current investigation reveals an important aspect of FLPs that can be exploited to improve their efficiency, that is, the more sterically hindered the FLP catalyst is, the lower is its turnover frequency. Full quantum chemical calculations with DFT for a family of different, experimentally known hydrogenation FLP catalysts shows that superior FLP catalysts can be designed by reducing the frustration (by reducing the steric demand and acid/base strength) in the FLP. However, as lowering the steric demand without reduction in the frustration can result in unwanted side reactions, the design of the most efficient FLP catalysts depends on tuning the system so that both the steric demand and the frustration are reduced appropriately.}, keywords = {Boranes, Hydrogenation, reaction mechanism, Steric Hindrance}, doi = {10.1002/cctc.201700289}, author = {Mane, M.V.}, editor = {Vanka, K.} } @article {44194, title = {Marginally hydrogenated triphasic titania nanotubes for effective visible-light photocatalytic hydrogen generation}, journal = {Energy Technology}, volume = {6}, year = {2018}, month = {FEB}, pages = {280-288}, type = {Article}, abstract = {

We report the first demonstration of hydrogen-annealed triphase TiO nanotubes (anatase-rutile-brookite) (T-ARB) as a visible-light-active photocatalyst for water splitting with high quantum efficiency. As-synthesized T-ARB was annealed under hydrogen atmosphere at 250 and 4508 degrees C for 2 h. We found that the tubular structures were retained in the hydrogenated TiO2 samples. It was observed that the concentrations of Ti3+ and the oxygen vacancies and their distribution significantly increased with respect to the hydrogen annealing temperature. Such changes in defects were found to be critical in enhancing the photocatalytic activity of the hydrogen-annealed triphase TiO2 nanotubes. The triphase TiO2 nanotubes hydrogen annealed at 450 degrees C were 16 times more efficient than pristine TiO2. Such an increase in the photocatalytic activity was explained by a triphase band diagram with defect states below the conduction band of each phase, which facilitated visible-light activity and easy transfer of charge carriers from one phase to another. Our study showed that the well-designed multiphase construction with oxygen vacancies enhanced the photocatalytic activity tremendously owing to the presence of a higher number of phase junctions.

}, keywords = {charge transfer, Defects, Hydrogenation, titania, water splitting}, issn = {2194-4288}, doi = {10.1002/ente.201700406}, author = {Preethi, Laguduva K. and Mathews, Tom and Walczak, Lukasz and Gopinath, Chinnakonda S.} } @article {44025, title = {One pot conversion of furfural to 2-methylfuran in the presence of PtCo bimetallic catalyst}, journal = {Clean Technologies and Environmental Policy}, volume = {20}, year = {2018}, month = {MAY}, pages = {703-713}, type = {Article in Press}, abstract = {

Biomass-derived furfural (FAL) is the platform chemical for synthesis of various value-added chemicals and fuels. One of the FAL-derived chemicals, i.e., 2-methylfuran (2-MF), is the potential biofuel due to its attractive chemical and physical properties. Various methods are reported for conversion of FAL to 2-MF which are operated at high temperature and high H2 pressure. In present work, one pot catalytic method was developed in batch mode process for conversion of FAL to 2-MF. Reactions are carried out in the presence of PtCo/C bimetallic catalyst under 0.5{\textendash}1 MPa H2 pressure. Monometallic and bimetallic catalysts with different Pt and Co loading were prepared by wet impregnation method, and catalysts were characterized by transmission electron microscopy, BET surface area, X-ray photoelectron spectroscopy, X-ray diffraction and inductive coupled plasma atomic emission spectroscopy techniques. 59\% 2-MF yield was achieved at 180 {\textdegree}C and lower (0.5 MPa) H2 pressure.

}, keywords = {2-Methylfuran, Bimetallic catalyst, Co-impregnation, furfural, Hydrodeoxygenation, Hydrogenation}, doi = {10.1007/s10098-017-1408-z}, author = {Dohade, M.G. and Dhepe, P. L.} } @article {44592, title = {Ti-doped Pd-Au catalysts for one-pot hydrogenation and ring opening of furfural}, journal = {Catalysts}, volume = {8}, year = {2018}, month = {JUN}, pages = {252}, abstract = {

Pd-Au bimetallic catalysts with different Pd/Au atomic ratios, supported on ordered structured silica (Hexagonal mesoporous silica-HMS, or Santa Barbara Amorphous-15-SBA-15) were evaluated for one-pot hydrogenation of furfural to 1,2-pentanediol. The surface and structural properties of the catalysts were deeply investigated by X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), N-2 adsorption isotherms (BET), Infrared spectroscopy (IR), and acid capacity measurements. XPS studies revealed that Ti doped supports had higher dispersion of the active phase, particularly in the case of Pd-Au materials in which Ti played an important role in stabilizing the metallic species. Among the various process conditions studied, such as temperature (160 degrees C), catalyst amount (10\% w/w), and reaction time (5 h), H-2 pressure (500 psi) was found to improve the 1,2-pentanediol selectivity. The SBA silica bimetallic Ti-doped system showed the best performance in terms of stability and reusability, after multiple cycles. Under specific reaction conditions, the synergism between Pd-Au alloy and Ti doping of the support allowed the ring opening pathway towards the formation of 1,2-pentanediol in furfural hydrogenation.

}, keywords = {Bimetallic catalyst, furfural, Hydrogenation, ring-opening}, issn = {2073-4344}, doi = {10.3390/catal8060252}, author = {Date, Nandan Shreehari and La Parola, Valeria and Rode, Chandrashekhar Vasant and Testa, Maria Luisa} } @article {47290, title = {3 d transition metal-catalyzed hydrogenation of nitriles and alkynes}, journal = {Chemistry-An Asian Journal}, volume = {15}, year = {2020}, month = {MAR}, pages = {690-708}, type = {Review}, abstract = {

Selective hydrogenation of nitriles and alkynes is crucial considering the vast applications of reduced products in industries and in the synthesis of bioactive compounds. Particularly, the late 3d transition metal catalysts (manganese, iron, cobalt, nickel and copper) have shown promising activity for the hydrogenation of nitriles to primary amines, secondary amines and imines. Similarly, semihydrogenation of alkynes to E- and Z-alkenes by 3d metals is adequately successful both via the transfer hydrogenation and by using molecular hydrogen. The emergence of 3d transition metals in the selective synthesis of industrially relevant amines, imines and alkenes makes this protocol more attractive. Herein, we provide a concise overview on the late 3d transition metal-catalyzed hydrogenation of nitriles to amines and imines as well as semihydrogenation of alkynes to alkenes.

}, keywords = {3d transition metal, Alkynes, Hydrogenation, nitriles, Semihydrogenation}, issn = {1861-4728}, doi = {10.1002/asia.201901762, Early Access Date = FEB 2020}, author = {Sharma, Dipesh M. and Punji, Benudhar} } @article {46965, title = {Efficient synthesis of gamma-valerolactone-a potential fuel from biomass derived levulinic acid using catalytic transfer hydrogenation over Hf@CCSO3H catalyst}, journal = {Catalysis Letters}, volume = {150}, year = {2020}, month = {JUL}, pages = {2038-2044}, type = {Article}, abstract = {

A new hafnium based carbonaceous catalyst (Hf@CCSO3H) was prepared by simultaneous carbonization and sulfonation of readily available glucose, followed by incorporation of hafnium metal on the surface of catalyst. The catalyst was well characterized using FT-IR, PXRD, EDX, SEM, C-13 CPNMR, XPS and BET analysis. The catalytic activity of Hf@CCSO3H was evaluated for synthesis of gamma-valerolactone-a potential fuel and green solvent. gamma-valerolactone was synthesized from biomass derived levulinic acid by catalytic transfer hydrogenation using 150 wt\% of catalyst at 200 celcius for 24 h in isopropanol solvent as a hydrogen donor. 100\% conversion of levulinic acid was achieved with an excellent yield of 96\% with more than 99\% selectivity of gamma-valerolactone as evident from GC analysis. The method developed is simple, efficient and economical. [GRAPHICS] .

}, keywords = {gamma-Valerolactone, Hydrogenation, levulinic acid, Transfer}, issn = {1011-372X}, doi = {10.1007/s10562-020-03119-w, Early Access Date = FEB 2020}, author = {Jori, Popat K. and Jadhav, Vrushali H.} } @article {47027, title = {Magnetically separable catalyst for condensation of renewable aldehydes and 2-methylfuran to saturated cyclic oxygenates}, journal = {Fuel Processing Technology}, volume = {197}, year = {2020}, month = {JAN}, pages = {106191}, type = {Article}, abstract = {

The saturated cyclic ethers produced from biomass derived aldehydes and 2-methylfuran are the potential diesel fuel candidates. The synthesis of saturated cyclic ethers is a two step process which involves acid catalyzed condensation of aldehydes with 2-methylfuran and the subsequent selective furan ring hydrogenation of the condensation products. Here, we designed a novel recyclable magnetic solid acid catalyst such as [Fe3O4@SiO2-Pr-Py-H][2HSO(4)(2-)] and employed for the condensation of 2-methylfuran with formaldehyde as model substrates and reaction parameters were optimized. Under the set reaction conditions, condensation of 2-methylfuran with several other aldehydes were also successfully achieved with very good yields. Further, several supported noble metal catalysts were screened in order to find suitable catalyst system for selective furan ring hydrogenation of condensation products. Among those, 5\% Pd/C was found to be very active and selective for furan ring hydrogenation without formation of ring opened products under very low hydrogen pressure at room temperature. Prepared catalysts were thoroughly characterized with sophisticated techniques.

}, keywords = {fuel additives, Hydrogenation, Hydroxyalkylation-alkylation, Magnetic solid acid, Organosilica}, issn = {0378-3820}, doi = {10.1016/j.fuproc.2019.106191}, author = {Tarade, Komal and Shinde, Suhas and Rode, Chandrashekhar} } @article {46738, title = {One pot hydrogenation of furfural to 2-methyl tetrahydrofuran over supported mono- and Bi-metallic catalysts}, journal = {ChemistrySelect}, volume = {5}, year = {2020}, month = {AUG }, pages = {9590-9600}, type = {Article}, abstract = {

2-Methyltetrahydrofuran is a valuable commercial product that can be obtained by direct hydrogenation of furfural. In the present study, among several carbon supported bimetallic Ir-Ni catalysts with different loadings screened, 4\% Ir-4\% Ni/C catalyst showed excellent activity in terms of direct conversion (99\%) to 2-MeTHF with a maximum selectivity of similar to 74\% at 220 degrees C and 750 psig, suppressing the formation of side chain as well as ring opening products. The catalytic activity was found to be mainly affected by catalyst preparation methods, metal loadings, surface composition, temperature, pressure and catalyst loading. HR-TEM and STEM revealed well dispersed Ir-Ni NPs having the particle sizes in the range of 2 to 5 nm. Different phases of Ir i. e. Ir degrees and IrO(2)as well as oxygen vacancies were found to be responsible for hydrogenation of furfural to 2-methyl furan while, Ni degrees and NiO were responsible for further hydrogenation to 2-MeTHF. The synergic effect between Ir and Ni was established through XPS, H-2-TPR analysis. With the help of some control experiments, the plausible reaction pathway was also proposed. The catalyst prepared by co-impregnation method found more effective than prepared by sequential addition method. At lower Ni loadings of 1\% and 2\%, low temperature of 160 degrees C as well as at low H(2)pressure of 250 psig, mixture of furfuryl alcohol and 2-methyl furan were formed selectively. Catalyst could be successfully reused up to 3 times without leaching of metals.

}, keywords = {2-Methyltetrahydrofuran, Bimetallic catalyst, furfural, Hydrogenation, OER type mechanism}, issn = {2365-6549}, doi = {10.1002/slct.202002322}, author = {Date, Nandan S. and Hengne, Amol M. and Huang, K. -W. and Chikate, Rajeev C. and Rode, Chandrashekhar V.} } @article {47686, title = {Active and recyclable gold metal nanoparticles catalyst supported on nitrogen-doped mesoporous carbon for chemoselective hydrogenation of cinnamaldehyde to cinnamyl alcohol}, journal = {Chemistry-An Asian Journal}, volume = {16}, year = {2021}, month = {SEP }, pages = {2702-2722}, type = {Article}, abstract = {Several supported gold metal catalysts with different Au nanoparticles sizes were prepared and evaluated for the chemoselective hydrogenation of cinnamaldehyde (CA) to cinnamyl alcohol (CAL). To investigate the structure-activity relationship, stability of catalyst, heterogeneity and recyclability, the structural characteristics of materials and Au catalysts (fresh and spent catalysts) were studied by employing variety of physico-chemical techniques. The interrelationship among Au nanoparticles size (nm) with turnover frequency (h(-1)) of Au catalysts has also been explored. Among the various Au catalysts tested, nitrogen-doped mesoporous carbon (NMC) supported Au catalyst having homogeneously dispersed (78.8\%) Au nanoparticles (1.6 nm) synthesized by sol-immobilization method (Au-NMC-SI) demonstrated improved catalytic activity affording 78\% CAL selectivity and 94.2\% CA conversion without using any promoter. Moreover, Au-NMC-SI catalyst exhibited good recyclability and stability. The catalyst synthesis approach described in this investigation opens up a novel strategy for the design of highly efficient metal nano-catalysts supported on NMC materials.}, keywords = {Au Nanoparticles, heterogeneous catalysis, Hydrogenation, Nitrogen-doped mesoporous carbon, Support-Metal interaction}, issn = {1861-4728}, doi = {10.1002/asia.202100552}, author = {Nagpure, Atul S. and Gogoi, Pranjal and Chilukuri, Satyanarayana V.} } @article {47746, title = {CuO as a reactive and reusable reagent for the hydrogenation of nitroarenes}, journal = {Applied Catalysis B-Environmental}, volume = {297}, year = {2021}, month = {NOV}, pages = {120417}, type = {Article}, abstract = {{Copper oxide (CuO) is used as a reusable solid reagent for hydrogenation of nitroarenes to aminoarenes. The use of CuO resulted in 100 \% conversion of 2.9 mmol of nitrobenzene to aniline in 45 s at room temperature using hydrazine hydrate as the reducing agent. During the reaction, CuO is converted to inactive metallic Cu which can be regenerated to active CuO by thermal oxidation. DFT simulations indicated facile formation of oxygen vacancies (EO}, keywords = {Copper vacancy, CuO, Hydrogenation, Nitroarene reduction, Oxygen defects, Reactive solids}, issn = {0926-3373}, doi = {10.1016/j.apcatb.2021.120417}, author = {Rajendran, K. and Pandurangan, N. and Vinod, C. P. and Khan, Tuhin S. and Gupta, Shelaka and Haider, M. Ali and Jagadeesan, D.} } @article {47439, title = {Elucidating the effect of solid base on the hydrogenation of C5 and C6 sugars over Pt{\textendash}Sn bimetallic catalyst at room temperature}, journal = {Carbohydrate Research}, volume = {505}, year = {2021}, month = {JUL}, pages = {108341}, type = {Article}, abstract = {

Conversion of sugars into\ sugar alcohols\ at room temperature with exceedingly high yields are achieved over Pt{\textendash}Sn/γ-Al2O3\ catalyst in the presence of calcined\ hydrotalcite. pH of the reaction mixture significantly affects the conversion and selectivity for sugar alcohols. Selection of a suitable base is the key to achieve optimum yields. Various solid bases in combination with Pt{\textendash}Sn/γ-Al2O3\ catalysts were evaluated for hydrogenation of sugars. Amongst all combinations, the mixture (1:1\ wt/wt) of Pt{\textendash}Sn/γ-Al2O3\ and calcined hydrotalcite showed the best results. Hydrotalcite helps to make the pH of reaction mixture alkaline at which sugar molecules undergo ring opening. The sugar molecule in open chain form has\ carbonyl group\ which can be polarized by Sn in Pt{\textendash}Sn/γ-Al2O3\ and Pt facilitates the hydrogenation. In the current work, effect of both; solid base and Sn as a promoter has been studied to improve the yields of sugar alcohols from various C5 and C6 sugars at very mild reaction conditions.

}, keywords = {Bimetallic catalyst, Hydrogenation, Hydrotalcites, Sugar, Sugar alcohols}, issn = {0008-6215}, doi = {10.1016/j.carres.2021.108341}, author = {Tathod, Anup P. and Dhepe, Paresh L.} } @article {47038, title = {Phosphorus ligands in hydroformylation and hydrogenation: a personal account}, journal = {Chemical Record}, year = {2021}, month = {MAR}, type = {Article; Early Access}, abstract = {

Metal-catalyzed hydroformylation and hydrogenation heavily rely on ligands, among which phosphorous ligands play a pivotal role. This personal account presents a selection of three distinct classes of phosphorous ligands, namely, monodentate meta-substituted phosphinites, bis-phosphites, and P-chiral supramolecular phosphines, developed in our group. The synthesis of these ligands, isolation, characterization, and their performance in transition metal-catalyzed hydroformylation, isomerizing hydroformylation, and asymmetric hydrogenation of olefins is summarized. The state of the art development in iron-catalyzed hydroformylation of alkenes and our contributions to the field is discussed. Use of phosphines enabled iron-catalyzed hydroformylation of alkenes under mild conditions. Thus, this account demonstrates the central role of phosphorus ligands in industrially relevant transformations such as hydrogenation and hydroformylation. The seemingly matured field of ligand discovery still holds significant potential and will steer the field of homogeneous catalysis.

}, keywords = {Homogeneous catalysis, Hydroformylation, Hydrogenation, Olefins, Phosphorus ligands}, issn = {1527-8999}, doi = {10.1002/tcr.202100007, Early Access Date = MAR 2021}, author = {Tewari, Tanuja and Kumar, Rohit and Chandanshive, Amol C. and Chikkali, Samir H.} } @article {47427, title = {Short enantioselective total synthesis of (+)-tofacitinib}, journal = {Tetrahedron Letters}, volume = {67}, year = {2021}, month = {MAR}, pages = {152838}, type = {Article}, abstract = {

An enantioselective total synthesis of Tofacitinib (CP-690,550), a Janus tyrosine kinase (JAK3) specific inhibitor has been achieved from the readily available 4-piperidone. Proline catalysed hydroxylation is the key step for the synthesis of enantiopure 1-benzyl-4-methylpiperidin-3-ol. (C) 2021 Elsevier Ltd. All rights reserved.

}, keywords = {aminohydroxylation, Hydrogenation, L-proline, piperidone}, issn = {0040-4039}, doi = {10.1016/j.tetlet.2021.152838}, author = {Mane, Kishor D. and Kamble, Rohit B. and Suryavanshi, Gurunath} } @article {47679, title = {Upgrading lignin derived monomers over basic supported metal catalysts}, journal = {Fuel}, volume = {306}, year = {2021}, month = {DEC}, pages = {121588}, type = {Article}, abstract = {Catalytic upgradation of aromatic monomers derived from lignin depolymerization is of high interest for the production of sustainable fuels and chemicals. Basic support has potential to provide advantages of better substrate-support interaction and reduced coke formation. Hence, we report the effect of various basic supports for metal catalysts (Pt, Pd, Ru) on the upgradation of phenol, guaiacol and eugenol. The complete hydrogenation product is achieved due to the strong interaction of the substrate with catalyst. Phenol is converted (55\%) into cyclohexanol (49\% yield) with low loading of Pt catalyst (1 wt\%), supported by the higher TON of 1 wt\% Pt/NaX (TON = 14844) than 3 wt\% Pt/NaX (TON = 5128). Effect of basic support with moderate (NaX) and strong (CHT) basic strengths are corelated for the higher cyclohexanone formation. Presence of strong basic sites and higher TON of 3 wt\% C-HT (TON = 6806) directs the significant substrate-support interaction. Catalytic activity and recyclability are supported by the comparable performance of recycle runs and characterizations of the fresh and spent catalysts.}, keywords = {aromatic monomers, Hydrogenation, lignin, Solid bases, supported metal catalyst, Upgradation}, issn = {0016-2361}, doi = {10.1016/j.fuel.2021.121588}, author = {Chaudhary, Richa and Dhepe, Paresh L.} } @article {47722, title = {Hydrogen solubility in biphasic liquid reaction mixture of cinnamaldehyde hydrogenation: experimental and mathematical modeling study}, journal = {Journal of Chemical Sciences}, volume = {134}, year = {2022}, month = {MAR}, pages = {1}, type = {Article}, abstract = {The solubility of hydrogen in the biphasic reaction mixture of cinnamaldehyde hydrogenation at 298 to 353 K has been determined in this work experimentally and by using a thermodynamic model. It is evident from many studies that the addition of extra phase, aqueous KOH as the fourth phase, to the three-phase cinnamaldehyde hydrogenation mixture [gas (hydrogen)-liquid (cinnamaldehyde + toluene)-solid (catalyst)] leads to enhancement of cinnamyl alcohol selectivity to a great extent. Determination of hydrogen solubility in this biphasic (organic-aqueous) reaction mixture is crucial to understand the intrinsic reaction kinetics of this reaction. The solubility of hydrogen was experimentally determined using a pressure drop method and reported in terms of Henry{\textquoteright}s constant. Firstly, hydrogen solubility was determined in pure components viz. toluene, cinnamaldehyde, and water followed by determination of its solubility in the cinnamaldehyde-toluene mixture, aqueous KOH, and eventually, in the reaction mixture containing the two immiscible liquid phases. The effect of changing concentrations in these mixtures and changing phase holdups in the total reaction mixture on hydrogen solubility was studied. Starting from pure components to the reaction mixture, the hydrogen solubility was predicted using a two-step thermodynamic approach involving regular solution theory and the theory of corresponding states. The solubility predictions from this thermodynamic model will be helpful in the accurate estimation of kinetic parameters.}, keywords = {biphasic liquid mixture, gas-liquid-liquid-solid [GLLS], hydrogen solubility, Hydrogenation, thermodynamic model}, issn = {0974-3626}, doi = {10.1007/s12039-021-01987-2}, author = {Khan, Muzammil Y. and Joshi, Sunil S. and Ranade, Vivek V.} } @article {47935, title = {Ionic liquids for the sustainable transformation of levulinic acid to gamma-valerolactone (GVL)}, journal = {Current Opinion in Green and Sustainable Chemistry}, volume = {35}, year = {2022}, month = {JUN}, pages = {100607}, type = {Article}, abstract = {

This short review is focused on recent findings on the role of ionic liquids (ILs) in catalysing the hydrogenation of levulinic acid (LA) to gamma valerolactone (GVL), which is a cascade reaction involving more than one type of reaction. A brief introduction on green aspects of IL as a catalyst followed by various types of ILs being used for hydrogenation of LA to GVL are discussed. The unique characteristics of ILs responsible for hydrogenation reaction are also explained along with the current and upcoming scenario of IL catalysed hydrogenation of LA to GVL.

}, keywords = {Biomass, Gamma valerolactone, Hydrogenation, Ionic liquid, levulinic acid}, issn = {2452-2236}, doi = {10.1016/j.cogsc.2022.100607}, author = {Kondawar, Sharda and Rode, Chandrashekhar} } @article {48133, title = {Reactivity of four coordinate iridium complex towards hydrogen: an experimental and computational study}, journal = {Journal of Organometallic Chemistry}, volume = {965}, year = {2022}, month = {MAY}, pages = {122317}, type = {Article}, abstract = {

Reaction of a four coordinate, 16-electron Ir complex, [Ir-(iPr)4(POCOP)(PPh3)] (4 ) (((iPr)4)(POCOP= 2,6-bis(di-isopropyl phosphinito)benzene, kappa(3)-C6H3-1,3-[OP((iPr))(2)](2)), with H-2 resulted in an oxidative addition product, cis-dihydride complex, cis-[Ir(H)(2) ((iPr)4)(POCOP)(PPh3)] ( cis-5 ) presumably via the intermediacy of a sigma complex, [Ir(eta(2)-H-2)((iPr)4)(POCOP)(PPh3)]. The cis-dihydride complex completely isomerizes to the trans-dihydride complex trans-[Ir(H)(2) ((iPr)4)(POCOP)(PPh3)] ( trans-5 ) under ambient conditions in about 3 h. It was found that the steric and electronic features on the iridium center have significant influence on the approach of H-2 onto the metal center followed by oxidative addition and isomerization. The isomerization process was studied in detail and all the mechanistic aspects have been elucidated using a combination of both experimental work and computation. The cis-dihydride complex isomerizes to the trans-dihydride by compensating the trans influence of the strongly trans-directing hydride ligand. A mechanism involving the exchange of the position of PPh3 with a hydride ligand cis to itself via PPh3 dissociation and re-coordination thereby resulting in the formation of the trans-dihydride complex, has been proposed for the isomerization. The cis-dihydride was found to be a highly active catalyst for hydrogenation of ethy-lene. A competing reactivity study of cis-dihydride between isomerization versus insertion of C2H4 into the Ir-H bond, was studied experimentally and computationally. (c) 2022 Elsevier B.V. All rights reserved.

}, keywords = {Hydrogenation, Insertion, iridium complex, isomerization, Oxidative addition, Reductive elimination}, issn = {0022-328X}, doi = {10.1016/j.jorganchem.2022.122317}, author = {Agrawal, Nisha K. and Dash, Soumya R. and Vanka, Kumar and Nethaji, Munirathinam and Jagirdar, Balaji R.} } @article {48065, title = {Reduction of carbon dioxide to dimethylformamide using ruthenium doped Mg/Al hydrotalcites under supercritical conditions}, journal = {Journal of CO2 Utilization}, volume = {61}, year = {2022}, month = {JUL}, pages = {102055}, type = {Article}, abstract = {

The utilization of carbon dioxide is one of the developing areas due to its significant contribution to global warming. Reducing carbon dioxide (CO2) to formic acid and its derivatives has gained importance because of its thermodynamic limitations and high industrial demand. In this article, we report the synthesis of dime-thylformamide (DMF) using ruthenium doped Mg/Al calcined hydrotalcite by CO2 hydrogenation in the presence of dimethylamine (DMA). At optimized conditions, complete conversion of dimethylamine was achieved with more than 92\% product yield at 170 degrees C and 13 MPa pressure with a reaction time of 6 h. Key catalyst properties were determined using X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), CO2-temper-ature programmed desorption (TPD), H-2 temperature-programmed reduction (TPR) and Fourier transform infrared (FTIR). The determination of surface morphology was carried out using field emission scanning electron microscope (FE-SEM) and high-resolution transmission electron microscopy (HR-TEM). At the same time, the chemical composition was verified by energy-dispersive X-ray (EDS). In addition, kinetic modeling is performed using the two site Langmuir-Hinshelwood-Hougen-Watson model. The regressed kinetic parameters gave an appropriate fit with experimental concentration values and activation energy is calculated as 413 kJ/mol K-1.

}, keywords = {Dimethylformamide, Hydrogenation, hydrotalcite, Langmuir-Hinshelwood-Hougen-Watson model, Supercritical carbon dioxide}, issn = {2212-9820}, doi = {10.1016/j.jcou.2022.102055}, author = {Chaudhary, Sagar D. and Rahatade, Shardul S. and Joshi, Sunil S. and Mali, Nilesh A.} } @article {48271, title = {Hydrogenation of levulinic acid to gamma-valerolactone over nickel supported organoclay catalyst}, journal = {Catalysis Today}, volume = {408}, year = {2023}, month = {JAN }, pages = {36-49}, type = {Article}, abstract = {

In this work, a series of Ni/Organoclay catalysts with different Nickel loadings were prepared by the wetimpregnation method for the catalytic hydrogenation of levulinic acid (LA) to gamma-valerolactone (GVL). Reaction parameters such as reaction temperature, pressure, solvent effect, and wt\% of catalyst were optimized to get excellent conversion of levulinic acid selectively to gamma-valerolactone. Ni/Organoclay with 30\% Nickel loading exhibited 100\% conversion of LA with 100\% selectivity towards GVL at 140 degrees C and 3.0 MPa H2 pressure using 1,4-dioxane as a solvent in 5 h. Different bulk and surface characterization techniques such as XRD, BET, FE-SEM, HR-TEM, XPS, XRF, NH3-TPD, and H2-Chemisorption were used to characterize the Ni/Organoclay catalyst. BET and NH3-TPD analysis showed that the pre-treatment of bentonite with surfactant (CTAB) improved the pore volume, surface area, and acidity of Organoclay which assisted in improving the conversion and selectivity of LA and GVL respectively.

}, keywords = {?-Valerolactone (GVL), Bentonite, Hydrogenation, Levulinic acid (LA), Nickel, organoclay}, issn = {0920-5861}, doi = {10.1016/j.cattod.2022.10.004}, author = {Kamble, Paresh A. and Vinod, C. P. and Rathod, Virendra K. and Kantam, Mannepalli Lakshmi} }