@article {42844, title = {Au(I)/Ag(I) co-operative catalysis: interception of Ag-bound carbocations with α-gold(I) enals in the imino-alkyne cyclizations with N-allenamides}, journal = {Chemical Communications}, volume = {52}, year = {2016}, month = {NOV}, pages = {14462-14465}, doi = {10.1039/C6CC08385D}, author = {Bagle, Pradip N. and Mane, Manoj V. and Vanka, Kumar and Shinde, Dinesh R. and Shaikh, Samir R. and Gonnade, Rajesh G. and Patil, Nitin T.} } @article {42693, title = {Expedient cobalt-catalyzed C{\textendash}H alkynylation of (enantiopure) benzylamines}, journal = {Organic Letters}, volume = {18}, year = {2016}, month = {OCT}, pages = {5252-5255}, abstract = {

A unified strategy for cobalt-catalyzed ortho-C-H bond alkynylation of benzylamines is reported. Simple, commercially available CoBr2 was used as a cobalt source. The developed alkynylation strategy is robust and efficient and has a broad substrate scope including 1 degrees, 2 degrees, and 3 degrees benzylamines. The mechanistic study shows that C-H bond cleavage is reversible, and the kinetic study illustrates that the rate of reaction depends solely on the catalyst.

}, keywords = {Terminal Alkynes; Bond Activation; Directed Functionalization;Aminoquinoline Benzamides; Ortho-C(Sp(2))-H Bonds; Mechanistic Insights; Selective Access; Carbon-Hydrogen; Nickel; Annulation}, doi = {10.1021/acs.orglett.6b02549}, author = {Landge, Vinod Gokulkrishna and Midya, Siba Prasad and Rana, Jagannath and Shinde, Dinesh R. and Balaraman, Ekambaram} } @article { ISI:000371754000043, title = {Gold vs rhodium catalysis: tuning reactivity through catalyst control in the C-H alkynylation of isoquinolones}, journal = {Organic Letters}, volume = {18}, number = {5}, year = {2016}, month = {MAR}, pages = {1056-1059}, publisher = {AMER CHEMICAL SOC}, address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA}, abstract = {

A site-selective C-4/C-8 alkynylation of isoquinolones catalyzed by gold and rhodium complexes is reported. A broad range of synthetically useful functional groups (-F, -Cl, -Br, -CF3, -OMe, alkyl, etc.) were tolerated, providing an efficient and robust protocol for the synthesis either C-4- or C-8-alkynylated isoquinolones.

}, issn = {1523-7060}, doi = {10.1021/acs.orglett.6b00175}, author = {Shaikh, Aslam C. and Shinde, Dinesh R. and Patil, Nitin T.} } @article {42949, title = {New dinor-cis-labdane diterpene and flavonoids with antimycobacterium activity from colebrookea oppositifolia}, journal = {Planta Medica Letters}, volume = {3}, year = {2016}, month = {MAR}, pages = {e20-e24}, abstract = {

The new 14,15-dinor-cis-labdane diterpene, named (+)-14,15-dinor-9α-hydroxy-cis-labd-11(E)-en-13-one (1), was isolated from the acetone extract of the aerial parts of Colebrookea oppositifolia, along with the known compounds alnustin (2), mosloflavone (3), flindulatin (4), 5,6,7-trimethoxy baicalein (5), tanetin (6), scutellarein 4'-methyl ether (7), apigenin (8), caffeic acid (9), anisofolin A (10), apigetrin (11), and forsythoside A (12). Structures of the new and known compounds were established by detailed analysis of 1D and 2D nuclear magnetic resonance studies. The isolated compounds 1{\textendash}12 were evaluated for their antimycobacterium activity against Mycobacterium tuberculosis H37Ra and Mycobacterium bovis in both dormant and active phases. Compounds 1, 7, and 8 exhibited inhibitory activity against M. tuberculosis with IC50 values in the range of 8.1{\textendash}55.0 {\textmu}M (MIC 14.4{\textendash}119.7 {\textmu}M) in the active phase and 7.4{\textendash}43.5 {\textmu}M (MIC 11.5{\textendash}123.3 {\textmu}M) in the dormant phase. Similarly 1, 7, and 8 exhibited inhibitory activity against M. bovis with IC50 values in the range of 4.1{\textendash}98.5 {\textmu}M (MIC 13.7{\textendash}161.0 {\textmu}M) in the active phase and 4.1{\textendash}111.1 {\textmu}M (MIC 13.0{\textendash}166.4 {\textmu}M) in the dormant phase.

}, doi = {10.1055/s-0042-102200}, author = {Chinchansure, Ashish A. and Arkile, Manisha A. and Shinde, Dinesh R. and Sarkar, Dhiman and Joshi, Swati P.} } @article { ISI:000374349600022, title = {Residue dependent hydrogen-bonding preferences in orthanilic acid-based short peptide beta-turn motifs}, journal = {RSC Advances}, volume = {6}, number = {42}, year = {2016}, month = {MAR}, pages = {35328-35331}, publisher = {ROYAL SOC CHEMISTRY}, address = {THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND}, abstract = {

This communication describes the competition between native beta-turn (C10) and 2-aminobenzenesulfonic acid (SAnt)( orthanilic acid)-based pseudo beta-turn (C11) in their hybrid peptides. Solid-state crystal structure and solution-state NMR studies revealed that C10 and C11 can be simultaneously observed under appropriate conditions. The variable temperature NMR coefficient data suggest that the isolated C11/C14 hydrogen bond is weaker in comparison with the consecutive C10 and C11 turns.

}, issn = {2046-2069}, doi = {10.1039/c6ra05684a}, author = {Jedhe, Ganesh S. and Vijayadas, Kuruppanthara N. and Kotmale, Amol S. and Sangtani, Ekta and Shinde, Dinesh R. and Gonnade, Rajesh G. and Rajamohanan, Pattuparambil R. and Sanjayan, Gangadhar J.} } @article {43880, title = {Coumarin-appended stable fluorescent self-complementary quadruple-hydrogen-bonded molecular duplexes}, journal = {Journal of Organic Chemistry}, volume = {82}, year = {2017}, month = {JUN}, pages = {6403-6408}, type = {Article}, abstract = {In this paper we report a coumarin-conjugated self-assembling system adorned with valuable features such as high duplex stability and a built-in fluorophore, which would augment its application potential. This system forms a highly :stalik molecular duplex in a nonpolar solvent (K-dim > 1.9 X 10(7) M-1 in CDCl3). Due to the fluorescent property of coumarin, these new structural motifs may find potential application in material chemistry and supramolecular chemistry.}, doi = {10.1021/acs.joc.7b01249}, author = {Kheria, Sanjeev and Rayavarapu, Suresh and Kotmale, Amol S. and Shinde, Dinesh R. and Gonnade, Rajesh G. and Sanjayan, Gangadhar J.} } @article {44154, title = {H-Bonding assisted self-assembly of anionic and neutral ligand on metal: a comprehensive strategy to mimic ditopic ligands in olefin polymerization}, journal = {Inorganic Chemistry}, volume = {56}, year = {2017}, month = {OCT}, pages = {12448-12456}, type = {Article}, abstract = {Self-assembly of two neutral ligands on a metal to mimic bidentate ligand coordination has been frequently encountered in the recent past, but self-assembly of an anionic ligand on a metal template alongside a neutral ligand remains an elusive target. Such a self-assembly is hampered by additional complexity, wherein a highly negatively charged anion can form intermolecular hydrogen bonding with the supramolecular motif, leaving no scope for self-assembly with neutral ligand. Presented here is the self-association of anionic ligand 3-ureidobenzoic acid (2a) and neutral ligand 1-(3-(diphenylphosphanyl)phenyl)urea (1a) on a metal template to yield metal complex [{COOC6H4-NH(CO)NH2}{Ph2PC6H4NH(CO)NH2}PdMeDMSO] (4a). The identity of 4a was established by NMR and mass spectroscopy. Along the same lines, 3-(3-phenylureido)benzoic acid (2b) and 1-(3-(diphenylphosphanyl)phenyl)-3-phenylurea (1b) self-assemble on a metal template to produce palladium complex [{COOC6H4NH(CO)NHPh}{Ph2PC6H4NH(CO)NHPh}PdMePy] (5c). The existence of 5c was confirmed by Job plot, 1-2D NMR spectroscopy, deuterium labeling, IR spectroscopy, UV-vis spectroscopy, model complex synthesis, and DFT calculations. These solution and gas phase investigations authenticated the presence of intramolecular hydrogen bonding between hydrogen{\textquoteright}s of 1b and carbonyl oxygen of 2b. The generality of the supramolecular approach has been validated by preparing six complexes from four monodentate ligands, and their synthetic utility was demonstrated in ethylene polymerization. Complex 4a was found to be the most active, leading to the production of highly branched polyethylene with a molecular weight of 55700 g/mol and melting temperature of 112 degrees C.}, doi = {10.1021/acs.inorgchem.7b01923}, author = {Mote, Nilesh R. and Patel, Ketan and Shinde, Dinesh R. and Gaikwad, Shahaji R. and Koshti, Vijay S. and Gonnade, Rajesh G. and Chikkali, Samir H.} } @article {44146, title = {Isomerizing hydroformylation of cashew nut shell liquid}, journal = {ChemCatChem}, volume = {9}, year = {2017}, month = {OCT}, pages = {3997-4004}, type = {Article}, abstract = {A small library of bisphosphorus ligands was evaluated in the rhodium-catalyzed isomerizing hydroformylation (I-HF) of cashew nut shell liquid (CNSL). The rhodium complex of 1,2-bis((di-tert-butylphosphanyl)methyl)benzene (BDTBPMB; L4) outperformed the other bisphosphite and bisphosphine ligands and unveiled a moderate selectivity of 28\% and 50\% in the I-HF of CNSL monoene and methoxy-protected monoene, respectively. The resultant aldehyde 16-(3-methoxyphenyl)hexadecanal P1 was isolated and its identity was fully established. Application of bis-phosphine ligand L4 in the I-HF of highly challenging CNSL cardanol (S3) and methoxy-protected CNSL cardanol yielded a linear selectivity of 74\%, although with reduced conversion. To demonstrate the synthetic utility of our strategy, the obtained aldehyde (derived from S3) was subjected to hydrogenation and the resultant 3-(16-hydroxyhexadecyl) phenol (P8) was isolated in 89\% isolated yield. High-pressure NMR investigation revealed selective formation of a bis-equatorial BDTBPMB-rhodium complex, which might be responsible for the excellent linear selectivity.}, doi = {10.1002/cctc.201700717}, author = {Pandey, Swechchha and Shinde, Dinesh R. and Chikkali, Samir H.} } @article {44114, title = {Modular approach towards functionalized highly stable self-complementary quadruple hydrogen bonded systems}, journal = {Organic \& Biomolecular Chemistry}, volume = {15}, year = {2017}, month = {DEC}, pages = {10087-10094}, type = {Article}, abstract = {Self-complementary quadruple hydrogen bonded systems have shown potential as key building blocks for developing various supramolecular polymers. Opportunities for the introduction of multiple functionalities would further augment, in principle, their application potential. Herein, we report a novel modular approach to simultaneously introduce two closely aligned side chains into AADD-type self-complementary quadruple hydrogen-bonding systems. Dithiane-tethered ureidopyrimidinone has been used as a reactive intermediate to efficiently attach closely aligned side chains by simply reacting with amines to form highly stable molecular duplexes. These duplexes featuring AADD-type arrays of hydrogen bonding codes are highly stable in non-polar solvents (K-dim > 1.9 x 10(7) M-1 in CDCl3) as well as in polar solvents (K-dim > 10(5) in 10\% DMSO-d(6)/CDCl3). Another notable feature of these self-assembling systems is their insensitivity to prototropy-related issues owing to their prototropic degeneracy, which will enhance their application potential in supramolecular chemistry.}, doi = {10.1039/c7ob02358h}, author = {Rayavarapu, Suresh and Kheria, Sanjeev and Shinde, Dinesh R. and Gonnade, Rajesh G. and Sanjayan, Gangadhar J.} } @article {44511, title = {Iron Catalyzed Hydroformylation of Alkenes under Mild Conditions: Evidence of an Fe(II) Catalyzed Process}, journal = {Journal of the American Chemical Society}, volume = {140}, year = {2018}, month = {MAR }, pages = {4430-4439}, abstract = {

Earth abundant, first row transition metals offer a cheap and sustainable alternative to the rare and precious metals. However, utilization of first row metals in catalysis requires harsh reaction conditions, suffers from limited activity, and fails to tolerate functional groups. Reported here is a highly efficient iron catalyzed hydroformylation of alkenes under mild conditions. This protocol operates at 10-30 bar syngas pressure below 100 degrees C, utilizes readily available ligands, and applies to an array of olefins. Thus, the iron precursor [HFe(CO)(4)](-)[Ph3PNPPh3](+) (1) in the presence of triphenyl phosphine catalyzes the hydroformylation of 1-hexene (S2), 1-octene (S1), 1-decene (S3), 1-dodecene (S4), 1-octadecene (S5), trimethoxy(vinyl)silane (S6), trimethyl(vinyl)silane (S7), cardanol (S8), 2,3-dihydrofuran (S9), allyl malonic acid (S10), styrene (S11), 4-methylstyrene (S12), 4-iBu-styrene (S13), 4-tBu-styrene (S14), 4-methoxy styrene (S15), 4-acetoxy styrene (S16), 4-bromo styrene (S17), 4-chloro styrene (S18), 4-vinylbenzonitrile (S19), 4-vinylbenzoic acid (S20), and allyl benzene (S21) to corresponding aldehydes in good to excellent yields. Both electron donating and electron withdrawing substituents could be tolerated and excellent conversions were obtained for S11-S20. Remarkably, the addition of 1 mol \% acetic acid promotes the reaction to completion within 16-24 h. Detailed mechanistic investigations revealed in situ formation of an iron-dihydride complex [H2Fe(CO)(2)(PPh3)(2)] (A) as an active catalytic species. This finding was further supported by cyclic voltammetry investigations and intermediacy of an Fe(0)-Fe(II) species was established. Combined experimental and computational investigations support the existence of an iron-dihydride as the catalyst resting state, which then follows a Fe(II) based catalytic cycle to produce aldehyde.

}, issn = {0002-7863}, doi = {10.1021/jacs.8b01286}, author = {Pandey, Swechchha and Raj, K. Vipin and Shinde, Dinesh R. and Vanka, Kumar and Kashyap, Varchaswal and Kurungot, Sreekumar and Vinod, C. P. and Chikkali, Samir H.} } @article {44384, title = {Unravelling the nucleophilicity of buten tides for 1,6-conjugate addition to p-quinone methides: a direct access to diversely substituted butenolide-derived diarylmethanes}, journal = {Organic Letters}, volume = {20}, year = {2018}, month = {MAY}, pages = {2787-2791}, abstract = {A Lewis acid catalyzed regioselective C-C bond is constructed through beta-addition of deconjugated butenolides with p-quinone methides in a 1,6-conjugate addition manner. Interestingly, Lewis acid catalyzed vinylogous Mukaiyama-Michael reaction of silyloxyfurans with p-QMs proceeds selectively through the alpha or gamma position exclusively. The reaction is mild with broad substrate scope, thus allowing easy access to a wide range of bis-arylated alpha-/beta-/gamma-substituted butenolides.}, doi = {10.1021/acs.orglett.8b00745}, author = {Sharma, Brijesh M. and Shinde, Dinesh R. and Jain, Ruchi and Begari, Eeshwaraiah and Satbhaiya, Shruti and Gonnade, Rajesh G. and Kumar, Pradeep} } @article {48713, title = {Synthesis of N-functionalized 2,3-disubstituted benzofurans/naphthofurans from para-quinone methides and isocyanides via the [4+1] annulation pathway}, journal = {Organic Chemistry Frontiers}, volume = {10}, year = {2023}, month = {JUL}, pages = {3746-3751}, type = {Article}, abstract = {

A scandium triflate catalyzed [4 + 1] cycloaddition reaction of 2-hydroxy-substituted para-quinone methides and isocyanides has been developed. This operationally simple, efficient and practical protocol provides straightforward access to a variety of N-functionalized 2,3-disubstituted benzofuran/naphthofuran derivatives with broad functional group compatibility and good scalability.

}, issn = {2052-4129}, doi = {10.1039/d3qo00048f}, author = {Kale, Someshwar B. and Kumar, Manish and Shinde, Dinesh R. and Krishna, Gamidi Rama and Das, Utpal} }