@article { ISI:000277325500008, title = {Dibutyltin oxide catalyzed aminolysis of oxalate to carbamate, oxamate and derivatives of imidazolidine trione}, journal = {Applied Organometallic Chemistry}, volume = {24}, number = {5}, year = {2010}, month = {MAY}, pages = {402-407}, publisher = {JOHN WILEY \& SONS LTD}, address = {THE ATRIUM, SOUTHERN GATE, CHICHESTER PO19 8SQ, W SUSSEX, ENGLAND}, abstract = {

Catalytic aminolysis of oxalates by simple and substituted ureas has been shown to give carbamates, oxamates and derivatives of imidazolidine trione. Various substituted ureas and oxalates were screened to verify the applicability of the protocol. The role of dibutyltin oxide as catalyst, effect of solvent and reaction conditions on product distribution pattern has been discussed. Copyright (C) 2010 John Wiley \& Sons, Ltd.

}, keywords = {Aminolysis, carbamate, derivative of imidazolidine trione, oxalate, oxamate, transfunctionalyzation, Urea}, issn = {0268-2605}, doi = {10.1002/aoc.1629}, author = {Kunde, Lalita B. and Kalyani, Vishwanath S. and Gupte, Sunil P.} } @article { ISI:000292011000004, title = {Eutectic mixture-directed kinetics of Diels-Alder reaction}, journal = {Indian Journal of Chemistry Section A-Inorganic Bio-Inorganic Physical Theoretical \& Analytical Chemistry}, volume = {50}, number = {6}, year = {2011}, month = {JUN}, pages = {788-792}, publisher = {NATL INST SCIENCE COMMUNICATION-NISCAIR}, address = {DR K S KRISHNAN MARG, PUSA CAMPUS, NEW DELHI 110 012, INDIA}, abstract = {

In the search for environmentally benign solvent media, a new class of solvents composed of mixtures of carbohydrates with urea or methylated urea has been noted to be effective in enhancing the reaction rates of a bimolecular organic reaction like the Diels-Alder reaction of cyclopentadiene with methyl acrylate. The viscosity of these media appears to be an important parameter in controlling the second order kinetics.

}, keywords = {carbohydrates, Cycloaddition, Diels-Alder reaction, Dimethylurea, kinetics, Reaction rates, solvent effects, Urea, viscosity}, issn = {0376-4710}, author = {Nagare, Amit S. and Kumar, Anil} } @article { ISI:000286850000004, title = {Oxidative carbonylation of amine using water-soluble palladium catalysts in biphasic media}, journal = {Journal of Molecular Catalysis A-Chemical}, volume = {334}, number = {1-2}, year = {2011}, month = {JAN}, pages = {20-28}, publisher = {ELSEVIER SCIENCE BV}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

Application of water-soluble palladium catalysts for oxidative carbonylation of aniline to N,N{\textquoteright} diphenyl urea (DPU) has been reported. The water-soluble palladium catalysts prepared from sulfonated N-containing ligands were found to be highly stable under reaction conditions and easily recyclable due to insoluble urea product in the reaction medium. This is in contrast to the sulfonated phosphine ligands, which are vulnerable to oxidation under reaction conditions, showing poor activity and stability. Commercially available as well as laboratory synthesized ligands were used for preparing water-soluble palladium catalysts, for oxidative carbonylation of aniline. The best activity was obtained for Pd complex with disodium 2,2{\textquoteright}-bipyridine-4,4{\textquoteright}-disulfonate (Bipy-DS) ligand. Under optimized conditions Pd(BipyDS)Pd(OAc)(2) catalyst gave TOF of similar to 210h(-1) with aniline conversion of similar to 97\% with similar to 91\% selectivity for N.N{\textquoteright}-diphenyl urea. It was found that the catalyst was easily reusable up to five times, with negligible loss in the catalytic activity. The effect of reaction parameters was investigated and a plausible reaction mechanism has been proposed. (C) 2010 Elsevier B.V. All rights reserved.

}, keywords = {Amine, Biphasic catalysis, Carbonylation, Urea, Water-soluble palladium catalyst}, issn = {1381-1169}, doi = {10.1016/j.molcata.2010.10.018}, author = {Didgikar, Mahesh R. and Joshi, Sunil S. and Gupte, Sunil P. and Diwakar, Makarand M. and Deshpande, Raj Madhukar and Chaudhari, Raghunath V.} } @article { ISI:000314743000016, title = {Solvent-free, highly efficient one-pot multi-component synthesis of 1-amido- and 1-carbamato-alkyl naphthols/phenols catalyzed by ethylammonium nitrate as reusable ionic liquid under neat reaction condition at ambient temperature}, journal = {Tetrahedron Letters}, volume = {54}, number = {7}, year = {2013}, month = {FEB}, pages = {672-675}, publisher = {PERGAMON-ELSEVIER SCIENCE LTD}, address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND}, abstract = {

A solvent-free, environmentally clean, mild, and simple one-pot multi-component protocol has been developed for the efficient synthesis of 1-amido- and 1-carbamato-alkyl naphthols/phenols in excellent yields via one-pot three-component condensation of various aldehydes, amides/carbamates/urea, and naphthols/phenols using ethylammonium nitrate (EAN) as a reusable ionic liquid catalyst under neat reaction condition at ambient temperature. (c) 2012 Elsevier Ltd. All rights reserved.

}, keywords = {Aldehyde, amide, Carbamate Phenol, Ethylammonium nitrate (EAN), Urea}, issn = {0040-4039}, doi = {10.1016/j.tetlet2012.12.004}, author = {Mulla, Shafeek Abdul Rashid and Salama, Tarek A. and Pathan, Mohsinkhan Y. and Inamdar, Suleman M. and Chavan, Santosh S.} } @article { ISI:000353289100023, title = {Interesting viscosity changes in the aqueous urea-ionic liquid system: effect of alkyl chain length attached to the cationic ring of an ionic liquid}, journal = {Journal of Solution Chemistry}, volume = {44}, number = {3-4, SI}, year = {2015}, month = {APR}, pages = {742-753}, publisher = {SPRINGER/PLENUM PUBLISHERS}, address = {233 SPRING ST, NEW YORK, NY 10013 USA}, abstract = {

In the present article, we demonstrate the effect of urea on the structure of the ionic liquids in their aqueous solutions through viscometric methods. We unravel the structure altering effect of urea in its aqueous solutions of ionic liquids possessing higher alkyl chains. The finding is an attempt to discern the anomalous behavior of urea as shown in the past with the help of many techniques. Interestingly, in the aqueous solutions of the imidazolium based ionic liquids having substitution of -C4H9 and -C6H13 groups on the imidazolium ring, urea exhibits kosmotropic behavior. Further increase in the substituted alkyl group such as -C8H17 alters the urea behavior to be chaotropic.

}, keywords = {Alkyl chain length, ionic liquids, Structure-breaker, Structure-maker, Urea, viscosity}, issn = {0095-9782}, doi = {10.1007/s10953-015-0320-6}, author = {Nanda, Raju and Rai, Gitanjali and Kumar, Anil} }