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Alcalase (Subtilisin A) was immobilized by simple hydrophobic adsorption onto various surface-grafted macroporous silicag els resulting in easy-to-prepare and stable biocatalystse nabling the efficient kinetic resolution (KR) and dynamic kinetic resolution (DKR)o fr acemic N-Boc-phenylalanine ethyl thioester with benzylamine.T he immobilized Alcalaseb iocatalysts, which retained their activity and selectivity when stored at 4 8 8Cf or more than ay ear, were testedi ne nzymatic aminolysis in batch and continuous-flow KRs resulting in (S)-N-Bocphenylalanine benzylamide in high enantiomeric purity. In KR of the racemict hioester by Alcalasecatalyzed aminolysis in ac ontinuous-flow reactor, the productivity (specific reactionr ate, r flow )a nd enantiomeric ratio (E)w ere studied in the 0-100 8 8C range.T he effect of the temperature on base-catalyzed racemization of the non-transformed (R)-thioester in ac ontinuous-flow reactor was also investigated in the 0-150 8 8Cr ange.T he continuous-mode DKR of the racemic thioester in as erialc ascade systemo fsix biocatalyst-filled columns at 50 8 8Cf or KR and five grafteds ilica gel-filled columns at 150 8 8Cf or racemization resulted in the formation of the (S)-benzylamide in 79% conversion, 8.17 g L À1 h À1 volumetric productivity and 98% ee. This is the first example of ad ynamic kinetic resolution of an amino acid derivative in continuous-flow mode using an alternating cascade of packed-bed enzyme reactors and racemization reactors kept at different temperatures.

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The lipase catalysed kinetic resolution of three trans-1-(2-hydroxycyclohexyl)-indoles in both batch and continuous-flow systems is reported. Ring opening of cyclohexene oxide by the corresponding indole followed by enzymatic acylation with vinyl acetate resulted in novel, highly enantioenriched indole-substituted cyclohexanols and cyclohexyl acetates. The effect of the temperature on enantiomeric ratio (E) and productivity (specific reaction rate, r flow ) in the continuous-flow mode acylation was studied at analytical scale in the 0-70°C range.Preparative scale kinetic resolution of the three indole derivatives was performed in mixed continuous-and recirculation-flow mode resulting in almost complete conversion and good to excellent enantiomeric purity of the products.