Synergism of Microwave Irradiation and Immobilized Lipase Catalysis in Synthesis of 4,8-dimethylnon-7-en-1yl (2E)-3-phenylpro-2-enolate

Abstract

Microwave irradiation and biocatalysis are important and rapidly developing technologies in green and sustainable engineering. The synergistic effect of microwave irradiation and lipase catalysis in transesterification of ethyl (2E)-3-phenylprop-2-enoate and 4,8-dimethylnon-7-en-1-ol was studied using immobilized enzymes such as Novozym 435, Lipase AYS amino, Lipozyme RMIM and Lipozyme TL IM. Novozym 435 was the best catalyst amongst studied. The effects of various parameters affecting the conversion and initial rates of transesterification were studied to establish kinetics and mechanism. There is synergism between enzyme catalysis and microwave irradiation, an increase in initial rates up to 2.3-fold was observed under microwave irradiation than that under conventional heating. With a substrate concentration of 0.03333 kmol/m3 of ethyl (2E)-3-phenylprop-2-enoate and 0.06667 kmol/m3 of 4,8-dimethylnon-7-en-1-ol in n-heptane, Novozym 435 offered a conversion of 94 % at 333 K in 21600 s. The analysis of initial rate data and progress curve data showed that the reaction obeys ternary complex ordered bi–bi mechanism with inhibition by 4,8-dimethylnon-7-en-1-ol. The theoretical predictions and experimental data match very well. These studies were also extended to other alcohols viz, n-butanol, n-pentanol, (3Z)-4,8-dimethylnon-3,7-dien-1-ol, benzyl alcohol, isoamyl alcohol, glycidol and 1,4-butanediol