Ionic Liquids as Designer Solvents for Biotransformations

In biotransformation reactions, ILs can act as tunable solvents or immobilizing agents or additives. They can also be coupled to substrates or other reagents (e.g., acylating agents in Hpase-catalyzed transesterifications [62]). Recent examples of chosen applications are presented below. 

The introduction of different cations in the IL, which served as a solvent, resulted in considerable changes in enantioselectivity of the reaction. The best results both in terms of selectivity and activity were obtained for [EMIM] [BF4]. However, in the case of heteroorganic substrates, namely hydroxymethylphosphinates, the best results were obtained using [BMIM] [PFe], while [BMIM] [BF4] proved to be completely useless [65c]. 

The use of ILs as solvents for biotransformation reactions is, of course, not limited to kinetic resolutions and the use of hydrolytic enzymes. Numerous other 

In hiphasic water/1L mixtures, the latter can he used as immohilization systems. This idea was used for the synthesis of conducting polyanihne hy IL-immohilized horseradish peroxidase [68]. Tuning the IL hydrophohicity hy changing the anionic component allowed the increase in the yield of the product hy altering the affinity of the product to the IL. After completion of the reaction, the IL phase was separated, facilitating the recovery of the enzyme. 

The TSIL used in this study has an ester moiety in its structure, which enables it to react in enzyme-catalyzed transesterification reaction. In the first part of the cycle, one of the enantiomers of the racemic alcohol is preferentially transformed into an ester of the IL-coupled acid. The other, unreacted enantiomer of the alcohol is then extracted, while the newly formed IL ester is treated with an excess of ethanol in the presence of the same enzyme. This process is accompanied by the regeneration of TSIL in the active form. The main advantage of the presented 

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