Biocatalysis has attracted special attention for the synthesis of industrially valuable ester compounds. This review focuses mainly on lipases obtained from different sources (commercially available or newly isolated) as biocatalysts for the synthesis of flavour and fragrance esters in solvent‐free as well as in non‐aqueous reaction media (i.e. organic and neoteric solvents). Neoteric solvents such as ionic liquids and supercritical fluids are greener and environmentally benign; their use in lipase‐catalysed ester synthesis is reviewed. The impact of an immobilization strategy to achieve higher yields (up to 99%) is discussed. The review also highlights the kinetic resolution of some important flavour/fragrance compounds synthesized using several chemo‐enzymatic strategies. Copyright © 2013 John Wiley & Sons, Ltd.

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A highly efficient polymer supported palladium-N-heterocyclic carbene (PS-Pd-NHC) catalytic system has been developed for direct reductive amination (DRA) of carbonyl compounds with primary/secondary amines in aqueous reaction medium. This new catalytic system represents a heterogeneous, recyclable and environmentally benign protocol. The developed methodology describes a simple one step approach for the synthesis of a wide variety of substituted amines exhibiting remarkable activity with excellent yield of a desired product. Furthermore, the catalyst was effectively recycled for six consecutive cycles without any significant loss in its catalytic activity.

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The film prepared using a blend of hydroxypropyl methyl cellulose (HPMC) and polyvinyl alcohol (PVA) was investigated for immobilization of Rhizopus oryzae lipase. These immobilized lipase films were characterized using a combination of techniques like SEM, TGA, FT-IR, and Karl Fischer titration analysis. The biocatalyst was subjected to transesterification reaction of benzyl alcohol with vinyl acetate and was optimized for various reaction parameters such as effect of support, molar ratio, solvent, concentration of biocatalyst, time and temperature. Furthermore, the developed methodology was then effectively applied to various alcohols for synthesis of industrially important acetates providing good to excellent yields of desired products. Interestingly, the experimental results demonstrated catalytic activity of immobilized lipase to be 4-fold greater than that of free lipase for transesterification reaction. The immobilized biocatalyst was effectively recycled for four consecutive cycles and exhibited remarkable stability for a period 90 days.