@article { ISI:000251244900020, title = {Environmentally benign catalytic hydroformylation-oxidation route for naproxen synthesis}, journal = {Industrial \& Engineering Chemistry Research}, volume = {46}, number = {25}, year = {2007}, note = {Joint 6th International Symposium on Catalysis in Multiphase Reactors/5th International Symposium on Multifunctional Reactors (CAMURE-6/ISMR-5-), Pune, INDIA, JAN 14-17, 2007}, month = {DEC}, pages = {8480-8489}, publisher = {AMER CHEMICAL SOC}, type = {Article}, address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA}, abstract = {

Hydroformylation of 6-methoxy-2-vinylnaphthalene (MVN), using homogeneous Rh(CO)acac) as a catalyst and a chelating bidentate ligand (1,2-bis-(diphenylphosphino) ethane, dppe), followed by oxidation of the product (2-(6-methoxynaphthyl) propanal, 2-MNP) has been studied as an alternative route for the synthesis Of D,L-naproxen. The feasibility of the MVN hydroformylation route has been demonstrated, and a detailed study has been reported on the key hydroformylation step. The roles of the catalyst, ligands, and solvents, as well as the effect of reaction conditions on the reaction rate and regioselectivity of the product 2-MNP, have been investigated. With Rh(CO)2(acac) as a catalyst and dppe as a ligand, \> 98\% selectivity to 2-MNP (an important precursor to D,L-naproxen) has been achieved. A possible mechanism to explain the variation in regioselectivity with Rh(CO)(2)(acac) as a catalyst and dppe as a ligand has been discussed. The kinetics of the hydroformylation step has been investigated and a rate equation has been proposed. The second step in the proposed route for naproxen-the oxidation of 2-MNP to 2-(6-methoxynaphthyl) propanoic acid (2-MNPA, or naproxen) - has been studied using Na2WO4 as a catalyst and tetrabutyl ammonium hydrogen sulfate (TBAHS) as the phase-transfer catalyst with H2O2 as the oxidant for the first time. Screening of the catalysts that consisted of the early transition metals, such as salts of tungsten, vanadium, and molybdenum showed that Na2WO4 gives the best performance for the oxidation step with \> 80\% selectivity to 2-(6-methoxynaphthyl)propanoic acid (2-MNPA/naproxen). This study would be valuable in developing a new environmentally benign route for naproxen synthesis.

}, issn = {0888-5885}, doi = {10.1021/ie0700866}, author = {Rajurkar, Kalpendra B. and Tonde, Sunil S. and Didgikar, Mahesh R. and Joshi, Sunil S. and Chaudhari, Raghunath V.} } @article { ISI:000268905100015, title = {Kinetics of arylation of 3-bromo-benzophenone with n-butylacrylate using NC palladacycle catalyst}, journal = {Journal of Molecular Catalysis A-Chemical}, volume = {309}, number = {1-2}, year = {2009}, month = {AUG}, pages = {111-116}, publisher = {ELSEVIER SCIENCE BV}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

The kinetics of arylation of n-butylacrylate (n-BA) with 3-bromo-benzophenone (BBP) using a monomeric palladacycle complex [Pd(ppy)(PPh(3))(OTs)](ppy=2-phenylpyridine) catalyst has been studied. The effect of concentration of the substrate, base (NaOAc), and catalyst was studied at three different temperatures (413-433 K). The rate was found to be first order with respect to catalyst, first order tending to zero order with respect to n-butylacrylate and NaOAc concentrations. The rate passed through a maximum with variation of BBP concentration. The observed results have been explained on the basis of formation of Pd species (PdX(2), PdX(3)(-), PdX(4)(2-), and Pd(2)X(6)(2-)) which are inactive for the Heck reaction. Various empirical rate equations were considered to fit the rate data and the best fitting model has been selected. The rates predicted by model were found to be in good agreement with the observed experimental data. (C) 2009 Elsevier B.V. All rights reserved.

}, keywords = {Arylation, Heck reaction, kinetics, Palladacycle}, issn = {1381-1169}, doi = {10.1016/j.molcata.2009.05.003}, author = {Atla, Shashi B. and Rajurkar, Kalpendra B. and Kelkar, Ashutosh A. and Chaudhari, Raghunath V.} } @conference { ISI:000287122200023, title = {Dynamic modeling of hydro- formylation of 1-decene on Rh/C catalyst in bubble colunm slurry reactor}, booktitle = {International Conference on Modeling, Optimization, and Computing}, series = {AIP Conference Proceedings}, volume = {1298}, year = {2010}, note = {International Conference on Modeling, Optimization, and Computing, Durgapur, INDIA, OCT 28-30, 2010}, month = {OCT}, pages = {143-150}, publisher = {Natl Inst Technol Durgapur; SERC, Dept Sci \& Technol; Caledonian Coll Engn; BRNS, Dept Atom Energy; DRDO, Minist Defence}, organization = {Natl Inst Technol Durgapur; SERC, Dept Sci \& Technol; Caledonian Coll Engn; BRNS, Dept Atom Energy; DRDO, Minist Defence}, address = {2 Huntington Quadrangle, STE 1NO1, Melville, NY 11747-4501 USA}, abstract = {

A dynamic model has been developed for the bubble column slurry reactor operating under non-isothermal conditions. The model consists of mass and heat balance equations for the gas and liquid phases and the catalyst particle. The model equations consisted of partial differential equations (PDE) which were converted to ordinary differential equations (ODE) by using finite difference relationships for the spatial derivatives and the ordinary differential equations for the time derivatives (Numerical Method of Lines-NMoL). The model was applied to describe the dynamic behaviour of bubble column slurry reactor during the hydroformylation of 1-decene on Rh/C catalyst. Model simulations were performed to obtain a meaningful path to steady state and to reproduce the other characteristics of the dynamic behaviour of the reactor. Under given conditions, the reaction required approximately 3750 seconds to reach the steady state concentrations at various reactor positions. It was observed with increase in the fluid velocities, the dynamics of the system was altered to 2500 seconds to reach the steady state condition. The effect of axial dispersion on the substrate concentration and the temperature rise along the reactor was further studied and discussed.

}, keywords = {axial dispersion, bubble column slurry reactor, Dynamic modeling, method of line, PDE solutions}, isbn = {978-0-7354-0854-8}, issn = {0094-243X}, doi = {10.1063/1.3516292}, author = {Upkare, Makarand M. and Rajurkar, Kalpendra B. and Das, Samir K. and Jaganathan, Rengaswamy}, editor = {Paruya, S. and Kar, S. and Roy, S.} } @conference { ISI:000287122200024, title = {Mathematical modeling and simulation of bubble column reactor for aerial liquid phase cyclohexane oxidation}, booktitle = {International Conference on Modeling, Optimization, and Computing}, series = {AIP Conference Proceedings}, volume = {1298}, year = {2010}, note = {International Conference on Modeling, Optimization, and Computing, Durgapur, INDIA, OCT 28-30, 2010}, month = {OCT}, pages = {151-159}, publisher = {Natl Inst Technol Durgapur; SERC, Dept Sci \& Technol; Caledonian Coll Engn; BRNS, Dept Atom Energy; DRDO, Minist Defence}, organization = {Natl Inst Technol Durgapur; SERC, Dept Sci \& Technol; Caledonian Coll Engn; BRNS, Dept Atom Energy; DRDO, Minist Defence}, address = {2 Huntington Quadrangle, STE 1no1, Melville, NY 11747-4501 USA}, abstract = {

Cyclohexane oxidation is an important but complex commercial reaction, wherein the desired product, K-A oil appears as an intermediates of the reaction sequence. A mathematical model has been developed for the bubble column reactor operating under isothermal conditions. The mass and energy model equations consisted of stiff ODEs. The model was applied to describe the behavior of bubble column reactor for aerial liquid phase cyclohexane oxidation. Effect of initial substrate concentration, catalyst loading and temperature was studied and discussed in detail. Conclusions were presented at the end of the study.

}, keywords = {K-A Oil Selectivity, Mathematical modeling, substrate conversion and product yield analysis}, isbn = {978-0-7354-0854-8}, issn = {0094-243X}, doi = {10.1063/1.3516293}, author = {Upkare, Makarand M. and Rajurkar, Kalpendra B. and Gupta, Pankaj R. and Jaganathan, Rengaswamy}, editor = {Paruya, S. and Kar, S. and Roy, S} } @article {46889, title = {Kinetics of hydroformylation of camphene using rhodium-phosphite catalyst}, journal = {International Journal of Chemical Kinetics}, volume = {52}, year = {2020}, month = {JUL}, pages = {485-495}, type = {Article}, abstract = {

Kinetics of hydroformylation of camphene was investigated in the presence of [Rh(CO)(2)(acac)]/P(OPh)(3) catalyst in a temperature range of 363-383 K. The influence of parameters such as stirring speed, camphene, catalyst, ligand concentrations, and partial pressures of H-2 and CO on the activity and selectivity of the catalyst has been studied. The rate showed a first-order dependence with respect to catalyst and camphene concentrations. The effect of partial pressure of hydrogen showed fractional order dependence. The plots of rate versus excess ligand, that is, (P(OPh)(3)) concentration and rate versus CO partial pressure passed through maxima and showed typical substrate/ligand inhibited kinetics. An empirical rate equation has been proposed and found to be in good agreement with the observed rate data. The kinetic parameters and activation energy were also evaluated.

}, keywords = {camphene, homogeneous, Hydroformylation, kinetics, rhodium-phosphite}, issn = {0538-8066}, doi = {10.1002/kin.21364, Early Access Date = APR 2020}, author = {Pagar, Nitin S. and Rajurkar, Kalpendra B. and Deshpande, Raj M.} }