02068nas a2200253 4500008004100000022001400041245006600055210006600121260009500187300001200282490000800294520115700302653004301459653002401502653002901526653005201555653001601607653001401623100001901637700002201656700002101678700001801699856009701717 2007 eng d a0021-951700aActivation and reactivity of epoxides on solid acid catalysts0 aActivation and reactivity of epoxides on solid acid catalysts a525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USAbACADEMIC PRESS INC ELSEVIER SCIENCEcDEC a148-1600 v2523 a

The aminolysis of epoxides over novel solid catalysts (Bronsted-acidic SBA-15 functionalized with propylsulfonic acid and Lewis-acidic Ti-MCM-41) is reported. The acidic properties of these catalysts were determined by FTIR spectroscopy and temperature-programmed desorption of pyridine and NH3, respectively. The mesoporous solid acids of the present study are reusable and exhibit significantly higher catalytic activities than known catalysts for opening of the oxirane ring with nitrogen (aromatic and aliphatic amines)-containing and oxygen (alcohols)-containing nucleophiles. A range of beta-amino, alcohols with high regioselectivity and stereoselectivity were synthesized. Adsorption studies as well as the sigmoid shape of the conversion- versus-time plots show that the epoxide and amine compete for adsorption on the acidic sites (-SO3H or Ti4+) on the catalyst surface. Epoxide adsorption and activation on acid sites are the more critical processes. Catalytic activity decreases with increasing basicity of the amines and/or the alcohol, as well as the dielectric constant of the solvent. (C) 2007 Elsevier Inc. All rights reserved.

10aaminolysis and alcoholysis of epoxides10abeta-Amino alcohols10aring opening of epoxides10aSBA-15 functionalized with propylsulfortic acid10aSolid acids10aTi-MCM-411 aSaikia, Lakshi1 aSatyarthi, J., K.1 aSrinivas, Darbha1 aRatnasamy, P. uhttps://library.ncl.res.in/content/activation-and-reactivity-epoxides-solid-acid-catalysts-001968nas a2200157 4500008004100000245017700041210006900218260000800287300001300295490000800308520130400316100001901620700002101639700002001660856013001680 2007 eng d00aComparative catalytic activity of Mn(Salen) complexes grafted on SBA-15 functionalized with amine, thiol and sulfonic acid groups for selective aerial oxidation of limonene0 aComparative catalytic activity of MnSalen complexes grafted on S cAUG a 225-2350 v1043 aSBA-15 molecular sieves were functionalized with propylamine, propylthiol and propylsulfonic acid groups. Mn(Salen)Cl complexes were grafted on these organo-functionalized SBA-15. The support and the type of organo-functional group influenced the electronic structure (oxidation state and redox behavior) and chemo selectivity of the Mn-complexes in the oxidation of limonene. The Mn ions were reduced from +3 to +2, the extent of this reduction on different supports decreasing in the order: SBA- 15-pr-SH > SBA- 15-prSO(3)H > SBA-15-pr-NH2- Mn(Salen)Cl supported on propylthiol-functionalized SBA-15 yielded the 1,2-limonene epoxide with 100% chemo- and regioselectivity. Higher electron density at the site of Mn ions and the consequent lower redox potential of the Mn-complexes on immobilization are the probable causes for their efficient and selective catalytic activity. Solvents, additives (N-MeIm) and co-reagents (iso-butyraldehyde), which facilitated formation of Mn2+ ions, enhance the catalytic activity. A part of the Mn complexes was leached out of the solid phase during the reaction and the extent of this with different catalysts decreased in the order: SBA-l5-pr-NH2-Mn(Salen)Cl > SBA- 15-pr-SO3H-Mn(Salen)Cl > SBA- 15-pr-SH-Mn(Salen)Cl. (C) 2007 Elsevier Inc. All rights reserved1 aSalkia, Lakshi1 aSrinivas, Darbha1 aRatnasamy, Paul uhttps://library.ncl.res.in/content/comparative-catalytic-activity-mnsalen-complexes-grafted-sba-15-functionalized-amine-thiol01262nas a2200229 4500008004100000022001400041245010100055210006900156260007300225300001200298490000800310520038700318653002700705653003700732653001400769653003600783100002800819700001900847700002100866700001800887856012700905 2007 eng d a0926-860X00aRegio- and stereoselective synthesis of beta-amino alcohols over titanosilicate molecular sieves0 aRegio and stereoselective synthesis of betaamino alcohols over t aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcOCT a145-1510 v3303 a

A novel application of titanosilicate molecular sieves in the synthesis of P-amino alcohols via aminolysis of epoxides, at mild and solvent-free conditions, is reported, for the first time. A range of beta-amino alcohols with nearly 100% regio- and stereoselectivity was produced over these reusable solid catalysts in high yields. (C) 2007 Elsevier B.V. All rights reserved.

10aAminolysis of epoxides10asynthesis of beta-amino alcohols10aTi-MCM-4110atitanosilicate molecular sieves1 aSatyarthi, Jitendra, K.1 aSaikia, Lakshi1 aSrinivas, Darbha1 aRatnasamy, P. uhttps://library.ncl.res.in/content/regio-and-stereoselective-synthesis-beta-amino-alcohols-over-titanosilicate-molecular-002333nas a2200301 4500008004100000022001400041245011200055210006900167260009500236300001200331490000800343520120700351653002801558653001901586653003101605653003101636653003301667653002001700100002101720700002901741700002001770700002801790700002601818700001901844700001801863700002001881856013001901 2008 eng d a0021-951700aActive sites in vanadia/titania catalysts for selective aerial oxidation of beta-picoline to nicotinic acid0 aActive sites in vanadiatitania catalysts for selective aerial ox a525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USAbACADEMIC PRESS INC ELSEVIER SCIENCEcOCT a165-1730 v2593 a

Vanadia/titania catalysts with varying vanadium content were prepared by impregnation using three different titania carrier materials of varying surface area, The structure of active vanadium species for beta-picoline oxidation was investigated. Vanadium is mainly in the +5 oxidation state as revealed by electron paramagnetic resonance (EPR) and V-51 magic-angle spinning nuclear magnetic resonance (V-51 MAS NMR) spectroscopy techniques. Diffuse reflectance UV-visible (DRUV-vis) spectroscopy and spectral deconvolution enabled identification of at least five different types of vanadium oxide species in these catalysts: monomeric tetrahedral VO43-, polymeric distorted tetrahedral VO3-, square pyramidal V2O5, octahedral V2O62- and V4+ oxide species. While both VO43- and VO3- species are active in beta-picoline oxidation, the latter having a distorted tetrahedral geometry yielded the desired products-picolinaldehyde and nicotinic acid. High surface area, anatase structure for the support and dispersed, distorted tetrahedral vanadium oxide species are the key parameters determining the activity and selectivity of these oxidation catalysts. (C) 2008 Elsevier Inc. All rights reserved.

10aActive vanadium species10aNicotinic acid10aOxidation of beta-picoline10aSelective aerial oxidation10aSpectroscopic investigations10aVanadia/titania1 aSrinivas, Darbha1 aHoelderich, Wolfgang, F.1 aKujath, Steffen1 aValkenberg, Michael, H.1 aRaja, Thirumalaiswamy1 aSaikia, Lakshi1 aHinze, Ramona1 aRamaswamy, Veda uhttps://library.ncl.res.in/content/active-sites-vanadiatitania-catalysts-selective-aerial-oxidation-beta-picoline-nicotinic-001523nas a2200253 4500008004100000022001400041245012700055210006900182260005700251300001000308490000800318520054500326653002400871653003100895653004400926653003500970653003001005100001901035700002201054700002401076700002101100700001801121856013001139 2008 eng d a1011-372X00aDouble metal cyanides as efficient solid acid catalysts for synthesis of beta-amino alcohols under solvent-free conditions0 aDouble metal cyanides as efficient solid acid catalysts for synt a233 SPRING ST, NEW YORK, NY 10013 USAbSPRINGERcJUN a24-310 v1233 a

A novel application of Fe-Zn double metal cyanide complexes as solid, acid catalysts for regioselective synthesis of beta-amino alcohols under solvent-free conditions via ring-opening of epoxides with amines is reported for the first time. The conversion of epoxides to beta-amino alcohols is nearly 100%. In the reaction with styrene oxide, regioselective beta-amino alcohol formation is higher with aromatic than with aliphatic amines. Strong Lewis acidic Zn(2+) ions in the catalyst are probably the active sites in this reaction.

10abeta-Amino alcohols10adouble metal cyanide (DMC)10aregioselective ring-opening of epoxides10aSingle crystal x-ray structure10asolid Lewis-acid catalyst1 aSaikia, Lakshi1 aSatyarthi, J., K.1 aGonnade, Rajesh, G.1 aSrinivas, Darbha1 aRatnasamy, P. uhttps://library.ncl.res.in/content/double-metal-cyanides-efficient-solid-acid-catalysts-synthesis-beta-amino-alcohols-under-002209nas a2200217 4500008004100000022001400041245009400055210006900149260007500218300001200293490000700305520136100312653003101673653003001704653003201734653002401766653003301790100002101823700001901844856012801863 2008 eng d a1571-101300aFunctionalized SBA-15 and its catalytic applications in selective organic transformations0 aFunctionalized SBA15 and its catalytic applications in selective a233 SPRING ST, NEW YORK, NY 10013 USAbSPRINGER/PLENUM PUBLISHERScJUN a114-1300 v123 a

Ordered, mesoporous SBA-15 functionalized with organic and inorganic moieties exhibits efficient catalytic activity in a variety of organic transformations. In this account, reviewing our own work, three-sets of surface-modified SBA-15 materials have been investigated. The first-set of materials consists of SBA-15 modified with organo-acidic (propyl thiol and propyl sulfonic acid) and basic (propyl amine and propyl adenine) moieties. The second-set of materials was prepared by grafting Mn complexes to the organo-functionalized SBA-15. The third-set composes of nanocrystalline metal oxides supported on SBA-15. All these catalysts have been characterized by structural and spectroscopic techniques. Catalytic activities of the first-set of solid materials have been investigated in acid/base-catalyzed reactions viz., ring-opening of epoxides with amines (producing beta-amino alcohols), esterification, three-component-Mannich reactions and cycloaddition of CO(2) to epoxides. The Mn complexes grafted on organofunctionalized SBA-15 are efficient catalysts for the chemo-, regio- and stereoselective aerial oxidation of monoterpenes at ambient conditions. TiO(x), VO(x), MoO(x) and WO(x) supported on SBA-15 catalyzed biomimetic oxyhalogenation of aromatic compounds. In all these reactions, the functionalized SBA-15 showed high selectivity.

10agrafted Mn-Salen complexes10aOrdered mesoporous silica10aorganofunctionalized SBA-1510aoxidation catalysts10aOxyhalogenation of aromatics1 aSrinivas, Darbha1 aSaikia, Lakshi uhttps://library.ncl.res.in/content/functionalized-sba-15-and-its-catalytic-applications-selective-organic-transformations-002289nas a2200265 4500008004100000022001400041245013500055210006900190260007300259300001200332490000800344520125900352653001801611653003201629653004501661653003001706653001501736653002201751100002401773700002801797700002401825700002101849700002201870856013101892 2009 eng d a0022-286000aMagnetic phase transition in valence tautomers as polymorphs of 3-iodolawsone: Single crystal X-ray structure, DSC and EPR studies0 aMagnetic phase transition in valence tautomers as polymorphs of  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcDEC a328-3350 v9383 a

Three polymorphs of 3-iodolawsone (I-III) have been isolated and characterized by single crystal X-ray diffraction, electron paramagnetic resonance (EPR) spectroscopy and differential scanning calorimetry (DSC) techniques. Polymorphs I and II were crystallized from methanol in two different valence tautomeric forms: hydroxynaphthoquinone (HNQ) and hydroxynaphthoseimquinone (HNSQ) as needles and thick plates, respectively. Polymorph III was crystallized from ethanol in HNQ form, as thin plates Chiral crystals of I belongs to the orthorhombic P2(1)2(1)2(1) space group: II and III belong to the monochnic non-centrosymmetric space group Cc. The molecules are packed via O-H O bonding and pi . pi stacking interactions. The study reveals that relatively stronger intermolecular H-bonding (2.02 angstrom) and most favoured pi . pi stacking (similar to 3 49 angstrom) interactions lead II to HNSQ radicals, presence of which was confirmed by EPR (g = 2.0052) spectroscopy. Interestingly, these materials exhibit crystal-to-crystal magnetic phase transition from polymorph I (diamagnetic) to polymorph II (paramagnetic structure) at 171.1 degrees C as identified by DSC and X-ray crystallographic studies (C) 2009 Elsevier B.V. All rights reserved

10a3-Iodolawsone10aHydroxynaphthoquinone (HNQ)10aHydroxynaphthosemiquinone radical (HNSQ)10aMagnetic phase transition10aPolymorphs10aValence tautomers1 aZaware, Santosh, B.1 aDagade-Waghmode, Shobha1 aGonnade, Rajesh, G.1 aSrinivas, Darbha1 aRane, Sandhya, Y. uhttps://library.ncl.res.in/content/magnetic-phase-transition-valence-tautomers-polymorphs-3-iodolawsone-single-crystal-x-ray-002449nas a2200229 4500008004100000022001400041245009600055210006900151260011700220300000900337490000800346520152700354653001301881653004301894653002501937653002401962653002001986653004102006100002002047700002102067856013102088 2009 eng d a0920-586100aSelective oxidations over zeolite- and mesoporous silica-based catalysts: selected examples0 aSelective oxidations over zeolite and mesoporous silicabased cat aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbCatalysis Soc India; Petrotech Soc; Indo US Sci & Technol ForumcMAR a3-110 v1413 a

Selective oxidation of hydrocarbons/terpenes in the liquid phase are reported over three categories of zeolite- and mesoporous silica-based catalysts: (1) transition metal complexes (metal phthalocyanines, copper acetate dimers and Co/Mn acetate trimer) encapsulated in zeolite-Y, (2) transition metal complexes (Mn-Salen), grafted on SBA-15, and (3) transition metal ions in framework positions of zeolites and mesoporous molecular sieves like Ti-silicates. Upon heterogenization, the metal complexes exhibited enhanced catalytic acitivity/selectivity. The causes for the enhanced catalytic activity/product selectivity have been explored. Dimer formation (copper acetate) or geometric distortion in the zeolite cavities (metal phthalocyanines) and consequent changes in energy levels and redox potentials are shown to modify the catalytic activity (in the selective oxidation of hydrocarbons) of the encapsulated metal complexes. In the case of Mn-Salen grafted on SBA-15, increasing the acidity of the siliceous surface (by -SO(3)H groups, for example) leads to a more facile reduction of the Mn ions and, thereby, enhanced catalytic activity in the selective epoxidation of limonene. When Ti ions are introduced in framework positions, reactive metal-oxo species are formed on contact with H(2)O(2) or O(2), Which influence the mode of O-O cleavage (heterolytic/homolytic) and product selectivity. The structure-function relationships in these catalysts are reported. (c) 2008 Elsevier B.V. All rights reserved.

10aMn-Salen10aOxidation of hydrocarbons and limonene10aReactive oxo species10aSelective oxidation10aTitanosilicates10aZeolite-encapsulated metal complexes1 aRatnasamy, Paul1 aSrinivas, Darbha uhttps://library.ncl.res.in/content/selective-oxidations-over-zeolite-and-mesoporous-silica-based-catalysts-selected-examples-000982nas a2200157 4500008004100000022001400041245011300055210006900168260011000237300001400347520027500361100001600636700002100652700002000673856013100693 2009 eng d a1359-734500aSynthesis of framework Ti-substituted, 3-D hexagonal, mesoporous Ti-SBA-12 for selective catalytic oxidation0 aSynthesis of framework Tisubstituted 3D hexagonal mesoporous TiS aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcSEP a6484-64863 a

Framework Ti-substituted, 3-D hexagonal mesoporous, Ti-SBA-12, obtained for the first time by direct hydrothermal synthesis, oxidises bulky molecules such as cyclohexene and cyclooctene to the epoxides with >96% selectivity at high conversion levels (>60%).

1 aKumar, Anuj1 aSrinivas, Darbha1 aRatnasamy, Paul uhttps://library.ncl.res.in/content/synthesis-framework-ti-substituted-3-d-hexagonal-mesoporous-ti-sba-12-selective-catalytic-001673nas a2200169 4500008004100000022001400041245009800055210006900153260007100222300001400293490000700307520099800314100002801312700002101340700002001361856012201381 2010 eng d a0887-062400aInfluence of surface hydrophobicity on the esterification of fatty acids over solid catalysts0 aInfluence of surface hydrophobicity on the esterification of fat a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcMAR a2154-21610 v243 a

The relative roles of surface acidity and hydrophobicity in the methylation of fatty acids (C(8) - C(18)) to the corresponding methyl esters were investigated over three solid acid catalysts: Fe-Zn double-metal cyanide (DMC), sulfated zirconia (SZ), and Al-MCM-41. The esterification reaction was faster and the apparent activation energy was lower over SZ and Al-MCM-41 than on DMC because of their higher acid strength, specific surface area, and pore diameter. Over SZ and Al-MCM-41, the apparent activation energy for esterification increased with the chain length of the fatty acid. A reverse trend, however, was observed over DMC. The relative adsorption of methanol and fatty acids (compared to water) was higher on DMC than on SZ and Al-MCM-41. Hence, in addition to the acidic and textural properties, surface hydrophobicity and relative surface coverage by reactants/products also play an important role in reactions of long-chain fatty acids with alcohols on solid catalysts.

1 aSatyarthi, Jitendra, K.1 aSrinivas, Darbha1 aRatnasamy, Paul uhttps://library.ncl.res.in/content/influence-surface-hydrophobicity-esterification-fatty-acids-over-solid-catalysts-001304nas a2200241 4500008004100000022001400041245010700055210006900162260005700231300001200288490000800300520042400308653002800732653003000760653003300790653001100823653002700834100001900861700001500880700002100895700001800916856012800934 2010 eng d a1011-372X00aRegiospecific oxyhalogenation of aromatics over SBA-15-supported nanoparticle group IV-VI metal oxides0 aRegiospecific oxyhalogenation of aromatics over SBA15supported n a233 SPRING ST, NEW YORK, NY 10013 USAbSPRINGERcJUL a190-2010 v1373 a

TiO(x), VO(x), MoO(x) and WO(x) supported on SBA-15 exhibit efficient catalytic activity for oxyhalogenation of aromatics with the H(2)O(2)-halide ion system. Unlike the hitherto known solid catalysts, these reusable catalysts yield the para-halogenated product with 100% selectivity at 298 K and moderate acidic pH (3-5). The catalytic activity was enhanced by five orders of magnitude when supported on SBA-15.

10aHaloperoxidase activity10aOrdered mesoporous silica10aOxyhalogenation of aromatics10aSBA-1510aSupported metal oxides1 aSaikia, Lakshi1 aRajesh, M.1 aSrinivas, Darbha1 aRatnasamy, P. uhttps://library.ncl.res.in/content/regiospecific-oxyhalogenation-aromatics-over-sba-15-supported-nanoparticle-group-iv-vi-002754nas a2200193 4500008004100000022001400041245011400055210006900169260011000238300001400348490000700362520194900369100002402318700002402342700002102366700002102387700002202408856013002430 2011 eng d a1144-054600aAntioxidant and anticancer activities of supramolecularly controlled magnetostructural halo-oximes of lawsone0 aAntioxidant and anticancer activities of supramolecularly contro aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcMAY a1615-16230 v353 a

Crystal engineering based on halogen bonding together with host-guest interactions of water molecules via H-bonding, stabilizing supramolecular architecture in chloro 1, bromo 2 and iodo 3 oximes of lawsone, is discussed. 1 and 2 crystallize in orthorhombic, non-centrosymmetric space group Pna2(1) while 3 crystallizes in monoclinic P2(1)/n space group. Non-covalent competitive interactions of asymmetric solvation and halogen bonding can have a large influence on the spin distribution in 1, 2 and 3 derivatives of spin carrier lawsone live polymer as revealed by single crystal X-ray and EPR studies. The significant C3-Cl/Br center dot center dot center dot O, C3-Cl/Br center dot center dot center dot H, O-H center dot center dot center dot O-C, C-H center dot center dot center dot pi and pi center dot center dot center dot pi interactions have been identified in the molecular assemblies leading to net magnetostructures of halo-oximes. Dimer-of-dimer-type tetrameric radical assembly of 3 and interacting bi- and monoradical chain on 2(1) axis in 1 and 2 have been identified. The proton-coupled electron transfers possibly govern the antioxidant nature in halooximes of spin carrier lawsone in terms of oxygen reduction to water molecules. Such activity is found to be directly proportional to the spin (radical) concentrations in 1 to 3 and increases in order 1 < 2 < 3 according to halogen bonding effect. The antioxidant chemical DPPH assays for scavenging of such free radicals result in similar trend of increasing order like 1 < 2 < 3, but the chemical in vitro as well as ex vivo SOD antioxidant activities and biological anticancer activity on MCF-7, Hela and HL-60 cell lines show the increasing order 3 < 2 < 1 according to H-bonding effect. This probably could be attributed to the conversion of superoxide radical ions into H(2)O(2), which leads to greater oxidative stress leading to apoptosis.

1 aZaware, Santosh, B.1 aGonnade, Rajesh, G.1 aSrinivas, Darbha1 aKhan, Ayesha, A.1 aRane, Sandhya, Y. uhttps://library.ncl.res.in/content/antioxidant-and-anticancer-activities-supramolecularly-controlled-magnetostructural-halo-002009nas a2200277 4500008004100000022001400041245011400055210006900169260007300238300001200311490000900323520098100332653002201313653004401335653002301379653004001402653001601442100002201458700001801480700002401498700002101522700002001543700002101563700001801584856012901602 2011 eng d a0022-286000aAzide derivatized anticancer agents of vitamin K-3: X-ray structural, DSC, resonance spectral and API studies0 aAzide derivatized anticancer agents of vitamin K3 Xray structura aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcDEC a288-2960 v10063 a

Compound 1 [1-imino (acetyl hydrazino)-Vitamin K-3], displays valence tautomerically related electronic isomers as Form land Form II. Form I exhibits 2D packing fragment with 1D ribbon chains of N-H center dot center dot center dot O hydrogen bonds and shows EPR silent features. While Form II is EPR active and exhibits biradical nature with double quantum transitions at g = 2.0040. H-1 NMR of compound 2, [1-imino (hydrazino carboxylate)-Vitamin K-3] and Form II exhibit pi delocalization via resonance assisted H-bonding [RAHB] effect compared to Form I. Molecular interactions in Form I and II are visualized by DSC. The electronic structures of compounds 1 and 2 have been correlated to their API values by measuring anticancer activities, mitochondrial potentials and DNA shearing patterns. Form II and compound 2 indicate mitochondria mediated apoptosis (similar to 75% cell death) while Form I causes 35% cell death. (C) 2011 Elsevier B.V. All rights reserved.

10aAnticancer agents10aAPI (Active Pharmaceutical Ingredients)10aElectronic isomers10aRAHB (resonance assisted H-bonding)10aVitamin K-31 aBadave, Kirti, D.1 aPatil, Yogesh1 aGonnade, Rajesh, G.1 aSrinivas, Darbha1 aDasgupta, Rajan1 aKhan, Ayesha, A.1 aRane, Sandhya uhttps://library.ncl.res.in/content/azide-derivatized-anticancer-agents-vitamin-k-3-x-ray-structural-dsc-resonance-spectral-002012nas a2200229 4500008004100000022001400041245010700055210006900162260007500231300001200306490000700318520115700325653001401482653002501496653001901521653001501540653002501555653002401580100002101604700002801625856012901653 2011 eng d a1571-101300aBiodiesel production from vegetable oils and animal fat over solid acid double-metal cyanide catalysts0 aBiodiesel production from vegetable oils and animal fat over sol a233 SPRING ST, NEW YORK, NY 10013 USAbSPRINGER/PLENUM PUBLISHERScSEP a145-1600 v153 a

Biodiesel comprises of fatty acid alkyl esters prepared from vegetable oils or animal fat by esterification/transesterification with short-chain alcohols (methanol or ethanol, for example). It is a biodegradable renewable fuel. Its production is growing exponentially due to greater concerns about environmental protection and depletion of fossil fuel resources. Further, its production from non-edible oils and animal fat is more desirable than from edible oils due to lower cost of non-edible feedstocks and elimination of food verses fuel issues. Solid acid catalysts are ideal for conversion of such low-grade oils to biodiesel. Biodiesel from non-edible oils can be produced by two methods: (1) simultaneous esterification of fatty acids and transesterification of fatty acid glycerides and (2) hydrolysis of glycerides followed by esterification. This account reports the catalytic performance of solid, Fe-Zn double-metal cyanide (DMC) complexes and other acid catalysts in these transformations for biodiesel production. The factors influencing the catalytic performance of the solid acid catalysts in biodiesel production are discussed.

10aBiodiesel10aDouble-metal cyanide10aEsterification10aHydrolysis10asolid acid catalysts10atransesterification1 aSrinivas, Darbha1 aSatyarthi, Jitendra, K. uhttps://library.ncl.res.in/content/biodiesel-production-vegetable-oils-and-animal-fat-over-solid-acid-double-metal-cyanide-001418nas a2200169 4500008004100000022001400041245009600055210006900151260007100220300001400291490000700305520073500312100003101047700002601078700002101104856012301125 2011 eng d a0887-062400aFactors Influencing the Kinetics of Esterification of Fatty Acids over Solid Acid Catalysts0 aFactors Influencing the Kinetics of Esterification of Fatty Acid a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcSEP a4106-41120 v253 a

The kinetics of esterification of fatty acids with alcohols over three different solid acid catalysts, viz., large pore zeolite-beta (H beta), micro-mesoporous Fe-Zn double-metal cyanide (DMC), and mesoporous Al-MCM-41, have been reported. Hydrophobicity of these catalysts increases in the order: Al-MCM-41 < H beta < DMC. The chain lengths of the fatty acid (C(8.0)-C(18.1)) and alcohol (C(1)-C(8)) molecules have been varied, and their influence on kinetic parameters has been studied. The present study reveals that porosity and surface hydrophobicity of the catalyst are the two important factors other than acid properties (concentration and strength of acid centers) that influence the esterification reaction.

1 aSatyarthi, Jitendra, Kumar1 aRadhakrishnan, Sambhu1 aSrinivas, Darbha uhttps://library.ncl.res.in/content/factors-influencing-kinetics-esterification-fatty-acids-over-solid-acid-catalysts-001490nas a2200157 4500008004100000022001400041245013800055210006900193260007100262300001400333490000700347520079800354100002801152700002101180856013101201 2011 eng d a0887-062400aFourier transform infrared spectroscopic method for monitoring hydroprocessing of vegetable oils to produce hydrocarbon-based biofuel0 aFourier transform infrared spectroscopic method for monitoring h a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcJUL a3318-33220 v253 a

A novel Fourier transform infrared spectroscopic method is reported, for the first time, to estimate the conversion of vegetable oil (soybean oil, for example) to hydrocarbon-based biofuel via hydroprocessing. The infrared peak attributed to the carboxyl group (O-C=O) is used as a marker to determine the conversion of fatty acid glycerides in soybean oil to hydrocarbons. Unlike the conventional gas chromatographic method, this new method of estimation is fast and requires no derivatization of the sample and predetermination of response factors of each chemical component in vegetable oil/product samples. H-1 and C-13 nuclear magnetic resonance spectroscopy techniques are also reported to substantiate and confirm the purity and product formation in the hydroprocessing reaction.

1 aSatyarthi, Jitendra, K.1 aSrinivas, Darbha uhttps://library.ncl.res.in/content/fourier-transform-infrared-spectroscopic-method-monitoring-hydroprocessing-vegetable-oils-001006nas a2200157 4500008004100000022001400041245012100055210006900176260011000245300001600355490000700371520031000378100002000688700002100708856011900729 2011 eng d a1359-734500aNovel application of a Fe-Zn double-metal cyanide catalyst in the synthesis of biodegradable, hyperbranched polymers0 aNovel application of a FeZn doublemetal cyanide catalyst in the  aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcAUG a10449-104510 v473 a

The use of Fe-Zn double-metal cyanide as a solid catalyst for synthesizing biodegradable, hyperbranched polymers from diacids and glycerol has been reported, for the first time, wherein acidity, micro-mesoporosity and hydrophobicity of the catalyst played an important role in controlling gelation.

1 aSebastian, Joby1 aSrinivas, Darbha uhttps://library.ncl.res.in/content/novel-application-fe-zn-double-metal-cyanide-catalyst-synthesis-biodegradable-001978nas a2200241 4500008004100000022001400041245011100055210006900166260009500235300001200330490000800342520104800350653002701398653002301425653003101448653002101479653004101500653001401541653001401555100001601569700002101585856013001606 2012 eng d a0021-951700aAminolysis of epoxides catalyzed by three-dimensional, mesoporous titanosilicates, Ti-SBA-12 and Ti-SBA-160 aAminolysis of epoxides catalyzed by threedimensional mesoporous  a525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USAbACADEMIC PRESS INC ELSEVIER SCIENCEcSEP a126-1400 v2933 a

The application of three-dimensional, mesoporous titanosilicates (Ti-SBA-12 and Ti-SBA-16) as reusable, solid catalysts for the synthesis of a range of beta-amino alcohols in high yields and selectivity through ring-opening of epoxides with amines at ambient and solvent-free conditions is reported, for the first time. These mesoporous titanosilicates (Si/Ti = 20-80) were prepared by a direct hydrothermal synthesis route adjusting the concentration of HCl (0.05-2 M) used in the synthesis. Ti ions in these catalysts were mostly substituted for Si in the framework. Water adsorption and Si-29 magic-angle spin nuclear magnetic resonance spectroscopy revealed that Ti-SBA-16 is more hydrophobic than Ti-SBA-12. Mesoporosity, three-dimensional architecture, surface hydrophobicity and easy access of Lewis acidic, framework-substituted Ti sites are the factors responsible for the superior activity of Ti-SBA-16 compared to Ti-SBA-12 and the hitherto known solid catalysts for this reaction. (C) 2012 Elsevier Inc. All rights reserved.

10aAminolysis of epoxides10abeta-Amino alcohol10aMesoporous titanosilicates10aMolecular sieves10aRing opening of epoxides with amines10aTi-SBA-1210aTi-SBA-161 aKumar, Anuj1 aSrinivas, Darbha uhttps://library.ncl.res.in/content/aminolysis-epoxides-catalyzed-three-dimensional-mesoporous-titanosilicates-ti-sba-12-and-001194nas a2200253 4500008004100000022001400041245005600055210005600111260011000167300001200277490000700289520032600296653001400622653001300636653001800649653001900667653002000686653002000706653004800726653002400774100002100798700003100819856009000850 2012 eng d a0376-471000aChallenges and opportunities in biofuels production0 aChallenges and opportunities in biofuels production aDR K S KRISHNAN MARG, PUSA CAMPUS, NEW DELHI 110 012, INDIAbNATL INST SCIENCE COMMUNICATION-NISCAIRcJAN a174-1850 v513 a

Biofuels are attractive alternative to petroleum diesel. They are renewable, non-toxic, biodegradable, carbon neutral and lead to reduced tailpipe emissions. This article presents the current state-of-art processes of their production and discusses the opportunities and future challenges in this area of research.

10aBiodiesel10abiofuels10aDeoxygenation10aHydrotreatment10aRenewable fuels10aSolid catalysts10aTransesterification (fatty acid glycerides)10aVegetable oils/fats1 aSrinivas, Darbha1 aSatyarthi, Jitendra, Kumar uhttps://library.ncl.res.in/content/challenges-and-opportunities-biofuels-production-002000nas a2200241 4500008004100000022001400041245014400055210006900199260007300268300001000341490000800351520108600359653003401445653002501479653002101504653002401525653001401549653001401563653002001577100001601597700002101613856012401634 2012 eng d a0920-586100aSelective oxidation of cyclic olefins over framework Ti-substituted, three-dimensional, mesoporous Ti-SBA-12 and Ti-SBA-16 molecular sieves0 aSelective oxidation of cyclic olefins over framework Tisubstitut aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcDEC a59-680 v1983 a

Framework Ti-substituted, three-dimensional, mesoporous titanosilicates, Ti-SBA-12 and Ti-SBA-16, were prepared by direct hydrothermal synthesis method. These catalysts showed catalytic activity higher than the hitherto known titanosilicates for the oxidation of cyclic olefins (cyclohexene and cyclooctene) with tert.-butyl hydroperoxide. An epoxide selectivity of 100% and olefin conversion greater than 92% were obtained. Cubic Ti-SBA-16 with interconnected cage-like mesopore structure was more active than hexagonal Ti-SBA-12. X-ray diffraction and diffuse reflectance UV-vis, Fourier transform infrared, Raman and electron paramagnetic resonance spectroscopies provided evidence for the substitution of Ti4+ (for Si4+) in the framework locations. The catalytic activity correlated with the concentration of framework-substituted, tetrahedral Ti4+ ions. Easy accessibility of the active sites and the three-dimensional mesoporous structure are the possible causes for the superior activity of these titanosilicate catalysts. (C) 2012 Elsevier B. V. All rights reserved.

10aEpoxidation of cyclic olefins10amesoporous materials10aMolecular sieves10aSelective oxidation10aTi-SBA-1210aTi-SBA-1610aTitanosilicates1 aKumar, Anuj1 aSrinivas, Darbha uhttps://library.ncl.res.in/content/selective-oxidation-cyclic-olefins-over-framework-ti-substituted-three-dimensional-001943nas a2200253 4500008004100000022001400041245009700055210006900152260007300221300001000294490000700304520104600311653001901357653002201376653002201398653003601420653001001456100001501466700002101481700002701502700002001529700002401549856011601573 2013 eng d a1566-736700aCatalytic activity of ZIF-8 in the synthesis of styrene carbonate from CO2 and styrene oxide0 aCatalytic activity of ZIF8 in the synthesis of styrene carbonate aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcFEB a36-400 v323 a

The catalytic activity of ZIF-8 in the synthesis of styrene carbonate from carbon dioxide and styrene oxide is presented. ZIF-8 crystals displayed catalytic activity even at temperatures as low as 50 degrees C, with styrene carbonate yields as high as similar to 54% at 100 degrees C. In contrast to many prior-art catalysts, solvents or co-catalysts were not required. Pyridine and ammonia were used as probe molecules to estimate the type and density of acid sites in fresh and reused ZIF-8 catalysts. DRIFT spectroscopy of adsorbed pyridine revealed the presence of both Bronsted (B) and Lewis (L) acid sites. The B-sites have nearly vanished in the case of recycled ZIF-8 catalysts. The simultaneous presence of both the acid sites and the nitrogen basic moieties from the imidazole linker in ZIF-8 promoted the adsorption of the CO2 on the solid surface and its further conversion to the cyclic carbonate. The ZIF-8 catalysts could be recycled and reused without significant loss in catalytic activity. Published by Elsevier B.V.

10aCO2 conversion10acyclic carbonates10aStyrene carbonate10aZeolitic imidazolate frameworks10aZIF-81 aZhu, Minqi1 aSrinivas, Darbha1 aBhogeswararao, Seemala1 aRatnasamy, Paul1 aCarreon, Moises, A. uhttps://library.ncl.res.in/content/catalytic-activity-zif-8-synthesis-styrene-carbonate-co2-and-styrene-oxide-001398nas a2200229 4500008004100000022001400041245009400055210006900149260007300218300001000291490000700301520054200308653002100850653002000871653001700891653004500908653003400953100001600987700002101003700002101024856012301045 2013 eng d a1566-736700aDirect synthesis of amides from amines using mesoporous Mn-SBA-12 and Mn-SBA-16 catalysts0 aDirect synthesis of amides from amines using mesoporous MnSBA12  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcJUL a36-400 v373 a

Manganese incorporated SBA-12 and SBA-16 catalyze the tandem reaction of aliphatic primary amine, aerial oxygen and ammonia solution at moderate conditions producing amide in yields as high as 50 mol%. The Mn-SBA-12 and Mn-SBA-16 catalysts with Si/Mn output molar ratio in the range 230 to 748 were prepared by the direct hydrothermal synthesis method and characterized. Weak acidity and Mn in +3 oxidation state are the key factors enable the synthesis of product amide in high yields. (C) 2013 Elsevier B.V. All rights reserved.

10aAerial oxidation10aAmide synthesis10aBenzyl amine10aManganese incorporated SBA-12 and SBA-1610aMesoporous Mn-silica catalyst1 aKumar, Anuj1 aNepak, Devadutta1 aSrinivas, Darbha uhttps://library.ncl.res.in/content/direct-synthesis-amides-amines-using-mesoporous-mn-sba-12-and-mn-sba-16-catalysts-001095nas a2200169 4500008004100000022001400041245013400055210006900189260011000258300001600368490000600384520034400390100002800734700002000762700002100782856012200803 2013 eng d a2046-206900aEfficient, direct synthesis of dimethyl carbonate from CO2 using a solid, calcined zirconium phenylphosphonate phosphite catalyst0 aEfficient direct synthesis of dimethyl carbonate from CO2 using  aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcOCT a23993-239960 v33 a

Direct synthesis of dimethyl carbonate (DMC) from CO2 and methanol with 100 mol% selectivity using a solid, reusable, hydrophobic, calcined zirconium phenylphosphonate phosphite catalyst is reported for the first time. DMC yield as high as 26 mmol g(-1) catalyst correlated with the concentration of acid and base sites is obtained.

1 aUnnikrishnan, Pulikkeel1 aVarhadi, Poonam1 aSrinivas, Darbha uhttps://library.ncl.res.in/content/efficient-direct-synthesis-dimethyl-carbonate-co2-using-solid-calcined-zirconium-001819nas a2200229 4500008004100000022001400041245008800055210006900143260007300212300001200285490000800297520095700305653005101262653002101313653003901334653003701373653001401410653001401424100001601438700002101454856011401475 2013 eng d a1381-116900aHydroxylation of phenol with hydrogen peroxide catalyzed by Ti-SBA-12 and Ti-SBA-160 aHydroxylation of phenol with hydrogen peroxide catalyzed by TiSB aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcMAR a112-1180 v3683 a

We report here, for the first time, the application of ordered, three-dimensional, mesoporous titanosilicates, Ti-SBA-12 and Ti-SBA-16, as reusable solid catalysts, for hydroxylation of phenol, an industrially important organic transformation. The reactions were conducted using 30% aqueous H2O2 as oxidant. The catalysts of this work are more efficient than the hitherto known mesoporous Ti-silicates. They are more para-product selective than TS-1 and other titanosilicates. Ti-SBA-12 exhibited higher activity and hydroquinone/catechol selectivity (by nearly two times) than Ti-SBA-16. H2O2 efficiency of similar to 90 mol% was obtained. Our study reveals that framework substituted Ti with pseudo-tetrahedral geometry, three-dimensional mesoporosity as well as surface structure are the unique features responsible for the high catalytic activity and selectivity of these titanosilicate catalysts. (C) 2012 Elsevier B.V. All rights reserved.

10aCatalytic liquid-phase hydroxylation of phenol10aMolecular sieves10aOrdered mesoporous titanosilicates10aOxidation with hydrogen peroxide10aTi-SBA-1210aTi-SBA-161 aKumar, Anuj1 aSrinivas, Darbha uhttps://library.ncl.res.in/content/hydroxylation-phenol-hydrogen-peroxide-catalyzed-ti-sba-12-and-ti-sba-16-001751nas a2200217 4500008004100000022001400041245014800055210006900203260007300272300001000345490000800355520086600363653001501229653002501244653002801269653003601297653002701333100002001360700002101380856013201401 2013 eng d a0926-860X00aInfluence of method of preparation of solid, double-metal cyanide complexes on their catalytic activity for synthesis of hyperbranched polymers0 aInfluence of method of preparation of solid doublemetal cyanide  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcAUG a51-600 v4643 a

Catalytic activity of a series of Fe-Zn double-metal cyanide (DMC) complexes with varying structural and acidic properties has been investigated for the synthesis of hyperbranched polyesters (HPs) from glycerol and succinic acid/adipic acid. The DMC complexes were prepared using different complexing and co-complexing agents. Hydrophobicity of the surface, Lewis acidity and micro-mesoporous architecture are the critical features of DMC enabled control on gelation process in preparing HPs of high degree of branching. The micro-mesoporous architecture of DMC acts as a nano-reactor for reactant molecules to form primary condensation products which further polymerize yielding dendrimers. Hyperbranched polyesters of degree of branching as high as 90% could be achieved without gelation using DMC catalysts. (C) 2013 Elsevier B.V. All rights reserved.

10aDendrimers10aDouble-metal cyanide10aheterogeneous catalysis10aHydrophobic solid acid catalyst10aHyperbranched polymers1 aSebastian, Joby1 aSrinivas, Darbha uhttps://library.ncl.res.in/content/influence-method-preparation-solid-double-metal-cyanide-complexes-their-catalytic-activity-001651nas a2200253 4500008004100000022001400041245011400055210006900169260011000238300001200348490000700360520067200367100002201039700002301061700002101084700002101105700002501126700002401151700002601175700002301201700002401224700002201248856012701270 2014 eng d a1144-054600aCu(II) conjugation along the transformation of a vitamin K-3 derivative to a dinaphthoquinone methide radical0 aCuII conjugation along the transformation of a vitamin K3 deriva aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcJAN a277-2840 v383 a

1,1'-Methide-bi-vitamin K-3 (B) has been isolated as a dinaphthoquinone methide radical (DNQM) by the transformation of 1-imino(acetylhydrazino)-vitamin K-3 (A). The transformation follows a biomimetic activation pathway mediated via Cu(II) ion catalyzed oxidative coupling. Single crystal X-ray and electron spin resonance (ESR) experiments combined with density functional calculations elucidate the ``resonance structure'' of the DNQM radical (B). Fluorescence investigations reveal that DNQM facilitates interaction with the cysteine residue. As compared to the parent substrate, B shows a depletion in the level of GSH, triggering apoptosis in HeLa cells.

1 aBadave, Kirti, D.1 aPatil, Shalaka, S.1 aKhan, Ayesha, A.1 aSrinivas, Darbha1 aButcher, Raymond, J.1 aGonnade, Rajesh, G.1 aPuranik, Vedavati, G.1 aPinjari, Rahul, V.1 aGejji, Shridhar, P.1 aRane, Sandhya, Y. uhttps://library.ncl.res.in/content/cuii-conjugation-along-transformation-vitamin-k-3-derivative-dinaphthoquinone-methide-002079nas a2200229 4500008004100000022001400041245013900055210006900194260007300263300001200336490000800348520116000356653001901516653002001535653005001555653002501605653001801630653003601648100002001684700002101704856012401725 2014 eng d a0926-860X00aEffects of method of preparation on catalytic activity of Co-Zn double-metal cyanide catalysts for copolymerization of CO2 and epoxide0 aEffects of method of preparation on catalytic activity of CoZn d aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcJUL a300-3080 v4823 a

Co-Zn double-metal cyanide (DMC) complexes are well-known catalysts for ring-opening polymerization of epoxides and co-polymerization of CO2 and epoxides. This work provides an insight on structure-activity relationship of DMC for poly(cyclohexene carbonate) synthesis. Seven samples of DMC were prepared by different methods and mode of reagent addition. Highly active catalyst could be synthesized even without using a co-complexing agent. CO2 adsorption studies revealed that higher the guest-host interaction higher would be the catalytic activity. High density and strength of Lewis acid sites, moderate crystallinity, low crystal symmetry (rhombohedral/monoclinic), Cl- ions and coordinated tert.-butanol (complexing agent) control the catalytic activity for polycarbonates. Chloride in the structure avoided induction period by increasing acidity of the catalyst and thereby, improving the guest-host interactions. Polycarbonates with CO2 incorporation as high as 86 mol%, average molecular weight of 20900 and polydispersity index of 1.8 were prepared at complete conversion of cyclohexene oxide. (C) 2014 Elsevier B.V. All rights reserved.

10aCarbon dioxide10aCO2 utilization10aCopolymerization of CO2 and cyclohexene oxide10aDouble-metal cyanide10aPolycarbonate10aStructure-activity relationship1 aSebastian, Joby1 aSrinivas, Darbha uhttps://library.ncl.res.in/content/effects-method-preparation-catalytic-activity-co-zn-double-metal-cyanide-catalysts-002468nas a2200157 4500008004100000022001400041245013200055210006900187260011000256300001600366490000600382520175200388100002102140700002102161856012802182 2015 eng d a2046-206900aEffect of alkali and alkaline earth metal ions on benzyl alcohol oxidation activity of titanate nanotube-supported Au catalysts0 aEffect of alkali and alkaline earth metal ions on benzyl alcohol aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcMAY a47740-477480 v53 a

Sodium titanate nanotubes (NaTNTs) were prepared by alkali treatment of anatase titania. They were then ion-exchanged with alkali and alkaline earth metal ions to get ATNTs (A = Li+, K+, Cs+, Mg2+, Ca2+, Sr2+ and Ba2+). Gold (1-5 wt%) was supported on these nanotubes by a deposition-precipitation method and investigated as a catalyst for the selective oxidation of benzyl alcohol with air/molecular oxygen (1 atm) under solvent-and alkali-free conditions. Detailed characterization by X-ray powder diffraction, high resolution transmission electron microscopy, N-2-physisorption, diffuse reflectance UV-visible spectroscopy, X-ray photoelectron spectroscopy and CO2-temperature-programmed desorption techniques revealed that the basicity of the catalyst influences the uptake, mean particle size, electronic properties and oxidation activity of the supported gold. Benzaldehyde formed with a selectivity of about 99%. The catalytic activity (turnover frequency) was found to have a direct relationship with the basicity and an inverse relationship with the Au particle size. Among the catalysts investigated, Au/BaTNTs, having higher basicity, smaller Au particles and higher metal dispersion, showed enhanced catalytic activity than the other Au/ATNT catalysts. Pd addition to Au leading to Au-Pd/BaTNTs increased the activity (TOF) but lowered the selectivity for benzaldehyde (80 wt%). Titanate nanotubes donate electron density to Au particles, yielding electron rich Au ions, which are responsible for activating molecular oxygen and oxidizing benzyl alcohol. Au/BaTNTs, having higher basicity and lower size Au nanoparticles than the other Au/ATNT, activates molecular oxygen more easily and thereby enhances the catalytic activity.

1 aNepak, Devadutta1 aSrinivas, Darbha uhttps://library.ncl.res.in/content/effect-alkali-and-alkaline-earth-metal-ions-benzyl-alcohol-oxidation-activity-titanate-001775nas a2200205 4500008004100000022001400041245013400055210006900189260007300258300001200331490000800343520094400351653002001295653004101315653002501356653001801381100002001399700002101419856012901440 2015 eng d a0926-860X00aFactors influencing catalytic activity of Co-Zn double-metal cyanide complexes for alternating polymerization of epoxides and CO20 aFactors influencing catalytic activity of CoZn doublemetal cyani aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcOCT a163-1720 v5063 a

Co-Zn double-metal cyanides (DMCs) show good catalytic activity towards copolymerization of epoxides and CO2. A deep insight into the structural aspects of the catalysts that control their catalytic performance is addressed in this work. Method of preparation of DMC catalysts was found to have influence on their structure, which in turn dictated their catalytic activity. Complexing agent (t-BuOH) and density of strong acid sites of DMC catalysts were found critical factors responsible for their activity. Selectivity of DMC towards polycarbonates depends on the amount of alkali ion content in their composition. Induction period of the catalysts was governed by the strength of acid sites and by the presence of dispersed ZnCl2 in the composition. This study provides an understanding of the prime features of DMC catalysts that can be tuned for high productivity of polycarbonates. (C) 2015 Elsevier B.V. All rights reserved.

10aCO2 utilization10aCopolymerization of epoxides and CO210aDouble-metal cyanide10aPolycarbonate1 aSebastian, Joby1 aSrinivas, Darbha uhttps://library.ncl.res.in/content/factors-influencing-catalytic-activity-co-zn-double-metal-cyanide-complexes-alternating-001613nas a2200205 4500008004100000245016200041210006900203260000800272300001200280490000700292520082600299100001901125700002301144700002001167700002801187700002601215700002101241700002101262856012401283 2016 eng d00aEffects of thermal treatment of ZnO-ZnCr2O4 catalyst on the particle size and product selectivity in dehydrocyclization of crude glycerol and ethylenediamine0 aEffects of thermal treatment of ZnOZnCr2O4 catalyst on the parti cSEP a602-6090 v573 aThe ZnO-ZnCr2O4 (Zn-Cr-O) sample obtained by decomposition of Zn-Cr hydrotalcite precursor was subjected to the thermal treatment at different temperatures and the physico-chemical properties of the Zn-Cr-O system were compared with its catalytic behavior in dehydrocyclization of crude glycerol and ethylenediamine (EDA). Upon high temperature treatment of Zn-Cr-O the Cr6+ ions underwent autoreduction to form stable Cr3+ species and the particle size of both ZnO and ZnCr2O4 increased dramatically. Thermal effect did not influence the intermolecular cyclisation of EDA to form pyrazine. By contrast, an inversely proportional dependence was found between the rate of formation of 2-methylpyrazine and the particle size of Zn-Cr-O whereas the rate of 2-pyrazinylmethanol was directly proportional to the particle size.1 aSarkari, Reema1 aKrishna, Vankudoth1 aSudhakar, Medak1 aRao, Tumula, Venkateshw1 aPadmasri, Aytam, Hari1 aSrinivas, Darbha1 aVenugopal, Akula uhttps://library.ncl.res.in/content/effects-thermal-treatment-zno-zncr2o4-catalyst-particle-size-and-product-selectivity01879nas a2200217 4500008004100000022001400041245011700055210006900172260007300241300001000314490000800324520104600332653002101378653002801399653001701427653002201444653002301466100002101489700002101510856013001531 2016 eng d a0926-860X00aSpectroscopy and catalytic activity study of gold supported on barium titanate nanotubes for styrene epoxidation0 aSpectroscopy and catalytic activity study of gold supported on b aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcAUG a61-720 v5233 a

Gold (0.5-5 wt.%) supported on barium titanate nanotubes (Au/BaTNT) were prepared, characterized and for the first time, investigated as catalysts for selective oxidation of styrene with oxygen (O-2 or H-2 + O-2) and peroxides (H2O2 or TBHP). Conversion of styrene enhanced when H-2 was co-added to O-2 in the reactions. Au/BaTNT activated O-2 and H-2 and produced H2O2 in situ for use in oxidations. Peroxides were found better oxidants than O-2. At optimized conditions, styrene oxide selectivity of 80.1 wt.% at styrene conversion of 60.5 wt.% was achieved over Au(1 wt.%)/BaTNT using TBHP. Au particles (5.0-7.4 nm) were dispersed and decorated on the walls of BaTNT. They exhibited superior performance to the known Au catalysts in styrene oxidation. Reactive oxygen species formed during oxidation reactions were followed with in situ spectral characterizations (diffuse reflectance UV-vis and FT -Raman). Au/BaTNT was reusable in four recycles with little loss in catalytic activity. (C) 2016 Elsevier B.V. All rights reserved.

10aAu Nanoparticles10areactive oxygen species10aspectroscopy10aStyrene Oxidation10aTitanate nanotubes1 aNepak, Devadutta1 aSrinivas, Darbha uhttps://library.ncl.res.in/content/spectroscopy-and-catalytic-activity-study-gold-supported-barium-titanate-nanotubes-styrene01786nas a2200217 4500008004100000022001400041245013300055210006900188260000800257300001200265490000800277520101600285653001301301653001801314653003001332653001601362653001601378100002201394700002101416856013101437 2017 eng d a0920-586100aSelective and reusable Pt-WO x /Al 2 O 3 catalyst for deoxygenation of fatty acids and their esters to diesel-range hydrocarbons0 aSelective and reusable PtWO x Al 2 O 3 catalyst for deoxygenatio cJUN a219-2260 v3093 aTungsten oxide promoted platinum catalysts (Pt-WOx/Al2O3) of varying composition were prepared by wet impregnation method and reduced in hydrogen atmosphere. X-ray powder diffraction and photoelectron spectroscopy revealed that Pt is completely reduced to metallic state while tungsten is in +6 and +5 oxidation state. Pt crystallite and particle sizes increased (from 1.2 to 1.4 nm and 2.5 to 3 nm, respectively) in presence of WOx (CO-chemisorption and transmission electron microscopy). Tungsten addition augmented strong acid sites. It enhanced significantly the catalytic activity of Pt/Al2O3 in deoxygenation of fatty acids and their methyl esters. Tungsten altered the reaction pathway from decarbonylation/decarboxylation to hydrodeoxygenation. A catalyst with 4 wt% Pt and 8 wt% W exhibited high catalytic performance. Complete conversion of oleic acid and octadecane product selectivity in the range 67.1 − 80.8% was obtained. Pt-WOx/Al2O3 is a stable and reusable fatty acid deoxygenation catalyst.10abiofuels10aDeoxygenation10aDiesel-range hydrocarbons10aFatty acids10aPt catalyst1 aJanampelli, Sagar1 aSrinivas, Darbha uhttps://library.ncl.res.in/content/selective-and-reusable-pt-wo-x-al-2-o-3-catalyst-deoxygenation-fatty-acids-and-their-esters00611nas a2200157 4500008004100000245008600041210006900127260000800196300002800204490000800232100002400240700003200264700002100296700002500317856011100342 2018 eng d00aModern trends in inorganic chemistry: celebration of inorganic chemistry in India0 aModern trends in inorganic chemistry celebration of inorganic ch cJUL aArticle Number: UNSP 750 v1301 aChikkali, Samir, H.1 aAnand, Venkataramanarao, G.1 aSrinivas, Darbha1 aKumbhar, Avinash, S. uhttps://library.ncl.res.in/content/modern-trends-inorganic-chemistry-celebration-inorganic-chemistry-india