@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:000288015800010, title = {Kinetics of hydroformylation of 1-octene in ionic liquid-organic biphasic media using rhodium sulfoxantphos catalyst}, journal = {Chemical Engineering Science}, volume = {66}, number = {8}, year = {2011}, month = {APR}, pages = {1631-1639}, publisher = {PERGAMON-ELSEVIER SCIENCE LTD}, address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND}, abstract = {

Biphasic hydroformylation of 1-octene was performed using rhodium sulfoxantphos catalyst dissolved in [BuPy][BF(4)] ionic liquid. Preliminary experiments proved this system to retain the catalytic complex within the ionic liquid phase and to maintain a high selectivity towards the linear aldehyde (n:iso ratio of 30) over several cycles. Process parameter investigation showed a first order dependence of the initial rate with respect to the catalyst and 1-octene concentrations, but a more complex behavior with respect to hydrogen (fractional order) and carbon monoxide partial pressures (inhibition at high pressures). Different mathematical models were selected based on the trends observed and evaluated for data fitting. Also, rate models were derived from a proposed mechanism, using Christiansen matrix approach. To calculate concentrations of substrates in the catalytic phase as required by this kinetic modeling, solubility measurements were preformed for the gases (pressure drop technique), as well as for 1-octene and n-nonanal (thermogravimetry analysis). (C) 2011 Elsevier Ltd. All rights reserved.

}, keywords = {Biphasic catalysis, Butylpyridinium tetrafluoroborate, kinetics, Parameter identification, Reaction engineering, solubility}, issn = {0009-2509}, doi = {10.1016/j.ces.2010.12.040}, author = {Deshpande, R. M. and Kelkar, Ashutosh A. and Sharma, A. and Julcour-Lebigue, C. and Delmas, Henri} } @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:000306193700016, title = {Kinetics of the Heck reaction in biphasic organic-ethylene glycol medium}, journal = {Reaction Kinetics Mechanisms and Catalysis}, volume = {106}, number = {2}, year = {2012}, month = {AUG}, pages = {457-473}, publisher = {SPRINGER}, address = {VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS}, abstract = {

PdCl2(bipy) was found to be an efficient and stable catalyst in biphasic medium (organic-glycol) for the Heck reaction. The kinetics of the Heck coupling of styrene with iodobenzene using the same catalyst was studied in a biphasic medium in a temperature range of 393-413 K. The rate was found to have a first order dependence tending to a fractional order, on the iodobenzene as well as catalyst concentration. The rate was found to have a complex dependence on the styrene concentration and passes through a maximum, showing typical substrate inhibition kinetics. The rate had a first order dependence on the base (morpholine) concentration. The trends observed for the influence of the different parameters on the activity of the catalyst are in agreement with the established mechanism for Heck reaction. An empirical rate model has been proposed to fit the observed rate data. The activation energy was found to be 72.91 kJ/mol. This is the first time that kinetic modeling of Heck reaction in a biphasic medium (organic-glycol) has been attempted.

}, keywords = {Biphasic catalysis, Heck reaction, kinetics, PdCl2(bipy) complex}, issn = {1878-5190}, doi = {10.1007/s11144-012-0437-1}, author = {Jagtap, Sangeeta Vijay and Deshpande, Raj Madhukar} } @article { ISI:000325204200090, title = {Cinnamic acid derivatives via heck reaction in an aqueous-biphasic catalytic system with easy catalyst-product separation}, journal = {Asian Journal of Chemistry}, volume = {25}, number = {15, A}, year = {2013}, month = {NOV}, pages = {8633-8637}, publisher = {ASIAN JOURNAL OF CHEMISTRY}, address = {11/100 RAJENDRA NAGAR, SECTOR 3,, SAHIBABAD 201 005, GHAZIABAD, INDIA}, abstract = {

A true biphasic [aqueous-organic] system for the coupling of water soluble sodium acrylate with different aryl halides for the synthesis of cinnamic acid derivatives has been developed, employing palladium catalysts that is soluble in organic phase. Amongst them, palladacycle was found to be stable in presence of water and could be recycled for four times with no loss in the activity. Such a system facilitates easy recycle of catalyst and also the removal of the salts from the catalyst phase, ensuring high activity with respect to cumulative turn over number (TON) and turn over frequency (TOF). The reaction was facilitated by organic as well as inorganic bases. The efficiency of the catalyst, role of organic/inorganic bases on the activity is reported.

}, keywords = {Biphasic catalysis, Heck reaction, Palladacycle, Separation}, issn = {0970-7077}, author = {Jagtap, Sangeeta Vijay and Deshpande, R. M.} }