@article { ISI:000262312300018, title = {First asymmetric total synthesis of penarolide sulfate A(1)}, journal = {European Journal of Organic Chemistry}, number = {36}, year = {2008}, month = {DEC}, pages = {6213-6224}, publisher = {WILEY-BLACKWELL}, type = {Article}, address = {COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA}, abstract = {

Penarolide sulfate A(1), with three contiguous stereogenic centers on a macrocyclic skeleton, affords promise as an alpha-glucosidase inhibitor. Herein, we describe the first asymmetric total synthesis of this natural product. A stereoselective strategy for rapid assembly of the complete framework of the 30-membered macrocyclic core is delineated herein. Sequential amidation and intramolecular Sonogashira cross-coupling reactions were pivotal to the success of our efforts. ((C) Wiley-VCH Verlag GmbH \& Co. KGaA, 69451 Weinheim, Germany, 2008)

}, keywords = {Asymmetric synthesis, C-C coupling, Dihydroxylation, epoxidation, Macrocycles, Regioselectivity, Total synthesis}, issn = {1434-193X}, doi = {10.1002/ejoc.200800680}, author = {Mohapatra, Debendra K. and Bhattasali, Debabrata and Gujar, Mukund K. and Khan, Mohammad Islam and Shashidhara, K. S.} } @article { ISI:000253382100048, title = {PdCl2(bipy) complex - an efficient catalyst for Heck reaction in glycol-organic biphasic medium}, journal = {Catalysis Today}, volume = {131}, number = {1-4}, year = {2008}, note = {4th Asia-Pacific Congress on Catalysis, Nanyang Technol Univ, Singapore, SINGAPORE, DEC 06-08, 2006}, month = {FEB}, pages = {353-359}, publisher = {ELSEVIER SCIENCE BV}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

The Palladium complex PdCl2(bipy) (1) was found to be efficient in catalyzing the Heck reaction of aryl halides in a biphasic system comprising ethylene glycol along with an organic solvent. A proper tailoring of the organic phase ensured that the leaching of the catalyst to the organic phase was negligible. The catalyst was active for the Heck reaction of a number of olefins, aryl halides, in presence of organic and inorganic bases. The PdCl2(bipy) catalyst was stable and could be recycled for five times without any loss in activity and selectivity. A major advantage of this work is that unlike hitherto reported biphasic systems; it does not employ a water-soluble ligand to achieve biphasic catalysis. (c) 2007 Elsevier B.V. All rights reserved.

}, keywords = {Biphasic catalysis, C-C coupling, Heck reaction, PdCl2(bipy) complex}, issn = {0920-5861}, doi = {10.1016/j.cattod.2007.10.043}, author = {Jagtap, Sangeeta Vijay and Deshpande, Raj Madhukar} } @article { ISI:000321434500006, title = {Palladium chloride catalyzed photochemical heck reaction}, journal = {Canadian Journal of Chemistry-Revue Canadienne De Chimie}, volume = {91}, number = {5}, year = {2013}, month = {MAY}, pages = {348-351}, publisher = {CANADIAN SCIENCE PUBLISHING, NRC RESEARCH PRESS}, address = {65 AURIGA DR, SUITE 203, OTTAWA, ON K2E 7W6, CANADA}, abstract = {

PdCl2 catalyzed carbon-carbon bond formation (Heck reaction) between substituted aryl halides and olefins was carried out without a ligand, under irradiation with UV-visible light. The results demonstrated that UV-visible light accelerated the rate of the reaction, leading to an excellent yield of corresponding products. The recovered palladium nanoparticles could be thermally recycled several times. PdCl2 gave excellent conversion up to the fifth addition of substrate.

}, keywords = {C-C coupling, Heck reaction, iodobenzene, photochemical reaction}, issn = {0008-4042}, doi = {10.1139/cjc-2012-0377}, author = {Waghmode, Suresh B. and Arbuj, Sudhir S. and Wani, Bina N. and Gopinath, Chinnakonda S.} } @article { ISI:000318393000043, title = {True water soluble palladium-catalyzed Heck reactions in aqueous-organic biphasic media}, journal = {Tetrahedron Letters}, volume = {54}, number = {21}, year = {2013}, month = {MAY}, pages = {2733-2736}, publisher = {PERGAMON-ELSEVIER SCIENCE LTD}, address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND}, abstract = {

A stable water soluble palladium catalyst has been demonstrated for the Heck reaction in a biphasic medium (water-non-polar organic solvent). Biphasic Heck reactions reported till now generally employ a non-polar solvent along with an aqueous polar water miscible organic solvent as the second phase. The efficiency of the Pd complex of TOTPS [Trisodium salt of tri-(ortho-tolyl) phosphine tri sulfonate] for the vinylation of different aryl iodides and olefins is demonstrated. The advantages of a co-solvent for this biphasic system have also been shown. The catalyst has been recycled efficiently retaining the activity with negligible loss of catalyst and without leaching of the Pd. (c) 2013 Elsevier Ltd. All rights reserved.

}, keywords = {Aqueous biphasic catalysis, C-C coupling, Heck reaction, Water-soluble catalyst}, issn = {0040-4039}, doi = {10.1016/j.tetlet.2013.03.067}, author = {Jagtap, Sangeeta Vijay and Deshpande, Raj Madhukar} } @article { ISI:000339493400008, title = {General approach to N-heterocyclic carbenes with a fused tetracyclic core: ligands for suzuki-miyaura cross-coupling reaction}, journal = {European Journal of Organic Chemistry}, number = {21}, year = {2014}, month = {JUL}, pages = {4482-4486}, publisher = {WILEY-V C H VERLAG GMBH}, address = {BOSCHSTRASSE 12, D-69469 WEINHEIM, GERMANY}, abstract = {

The synthesis of an N-heterocyclic carbene (NHC) based on a tetracyclic scaffold by using simple, general, and scalable chemistry is disclosed. The developed route is suitable for introducing multiple substitutions on the tetracyclic scaffold. The utility of the present NHC as a ligand in the Suzuki-Miyaura cross-coupling reaction is demonstrated with a low catalyst loading.

}, keywords = {C-C coupling, carbenes, Homogeneous catalysis, N ligands, synthetic methods}, issn = {1434-193X}, doi = {10.1002/ejoc.201402378}, author = {Sutar, Revannath L. and Kumar, Vinod and Shingare, Rahul D. and Thorat, Shridhar and Gonnade, Rajesh G. and Reddy, D. Srinivasa} } @article {48450, title = {Intrinsic charge polarization in Bi19S27Cl3 nanorods promotes selective C-C coupling reaction during photoreduction of CO2 to ethanol}, journal = {Advanced Materials}, volume = {35}, year = {2023}, month = {FEB}, type = {Article}, abstract = {

Obtaining multi-carbon products via CO2 photoreduction is a major catalytic challenge involving multielectron-mediated C-C bond formation. Complex design of multicomponent interfaces that are exploited to achieve this chemical transformation, often leads to untraceable deleterious changes in the interfacial chemical environment affecting CO2 conversion efficiency and product selectivity. Alternatively, robust metal centers having asymmetric charge distribution can effectuate C-C coupling reaction through the stabilization of intermediates, for desired product selectivity. However, generating inherent charge distribution in a single component catalyst is a difficult material design challenge. Here, a novel photocatalyst, Bi19S27Cl3, is presented which selectively converts CO2 to a C-2 product, ethanol, in high yield under visible light irradiation. Structural analysis through transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and X-ray absorption spectroscopy reveals the presence of charge polarized bismuth centers in Bi19S27Cl3. The intrinsic electric field induced by charge polarized bismuth centers renders better separation efficiency of photogenerated electron-hole pair. Furthermore, charge polarized centers yield better adsorption of CO* intermediate and accelerate the rate determining C-C coupling step through the formation of OCCOH intermediate. Formation of these intermediates is experimentally mapped by in situ Fourier-transform infrared spectroscopy and further confirmed by theoretical calculation.

}, keywords = {C-C coupling, charge polarization, CO2 reduction, Ethanol, Photocatalysis}, issn = {0935-9648}, doi = {10.1002/adma.202205994}, author = {Das, Kousik and Das, Risov and Riyaz, Mohd and Parui, Arko and Bagchi, Debabrata and Singh, Ashutosh Kumar and Singh, Abhishek Kumar and Vinod, Chathakudath P. and Peter, Sebastian C.} }