Research Article Microwave Assisted Enzymatic Kinetic Resolution of (±)-1-Phenyl-2-propyn-1-ol in Nonaqueous Media Saravanan Devendran and Ganapati D. Yadav Department of Chemical Engineering, Institute of Chemical Technology, Matunga, Mumbai 400 019, India Correspondence should be addressed to Ganapati D. Yadav; gdyadav@yahoo.com Received 12 April 2013; Revised 20 October 2013; Accepted 2 December 2013; Published 23 February 2014 Academic Editor: Luciana Rocha Barros Gonc ¸alves Copyright © 2014 S. Devendran and G. D. Yadav. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Kinetic resolution of 1-phenyl-2-propyn-1-ol, an important chiral synthon, was studied through trans-esterifcation with acyl acetate to investigate synergism between microwave irradiation and enzyme catalysis. Lipases from diferent microbial origins were employed for the kinetic resolution of (R/S)-1-phenyl-2-propyn-1-ol, among which Candida antarctica lipase B, immobilized on acrylic resin (Novozym 435), was found to be the best catalyst in n-hexane as solvent. Vinyl acetate was the most efective among diferent acyl esters studied. Te efect of various parameters was studied in a systematic manner. Defnite synergism between microwave and enzyme was observed. Te initial rate was improved around 1.28 times under microwave irradiation than conventional heating. Under optimum conditions, maximum conversion (48.78%) and high enantiomeric excess (93.25%) were obtained in 2h. From modeling studies, it is concluded that the reaction follows the Ping-Pong bi-bi mechanism with dead end alcohol inhibition. Kinetic parameters were obtained by using nonlinear regression. Tis process is green, clean, and easily scalable as compared to the chemical process. 1. Introduction Enantiomeric pure chemicals are needed for synthesis of optically active compounds that have signifcant market values across a variety of industries [1], among which chiral secondary alcohols have several applications in pharmaceu- tical and chemical industries, such as chiral auxiliaries, and they can be easily derivatized with diferent functional groups [2]. In comparison with classical chemical methods such as preferential crystallization, diastereomerization, chromato- graphic separation, and asymmetric reduction by chiral metal oxides, biocatalytic processes are broadly accepted as good options to prepare optically pure secondary alcohols [3]. Biocatalysts score over chemical processes because they ofen possess high stereo-, chemo-, and regio-selectivity. Biocat- alytic systems can be operated at mild operating conditions that reduce byproduct formations and are recyclable and easily adoptable in nonaqueous and neoteric solvents. Biocat- alytic processes are reported as simple and cost efective for the synthesis of single enantiomeric compounds. However, the major drawback of these processes is the fact that they are slow in nature and need to be intensifed in order to meet industrial requirements [4–6]. Among various biocatalytic paths, lipase catalyzed kinetic resolution of racemic mixtures have been favored for prepar- ing the optically active secondary alcohols through hydrolysis and transesterifcation reactions. Lipases have inherent ability to accept a broad range of substances and do not require expensive cofactors like NAD(P)H. Lipases are readily avail- able from animal, plant, and microbial sources and remain active in both organic and neoteric solvents like ionic liquids and supercritical carbon dioxide (scCO 2 ). However, alcohol dehydrogenases catalyzed asymmetric reduction requires expensive cofactors for its catalytic activity and is also less adoptable to nonaqueous media [7, 8]. In recent years, microwave irradiation, a green and clean alternative energy source, has been employed to enhance the reaction rates and selectivities for organic synthesis as well as materials production [9, 10]. In the conventional heating, the rate of heat transfer from external heating source to reaction system depends on the thermal conductivity of reaction vessel, which might lead to higher temperature at Hindawi Publishing Corporation BioMed Research International Volume 2014, Article ID 482678, 9 pages http://dx.doi.org/10.1155/2014/482678