A practical chemo-enzymatic approach to highly enantio-enriched cyanohydrin acetates

The preparation of enantiopure cyanohydrin acetates via enzymatic hydrolysis has been investigated by screening a range of biocatalysts and reaction conditions. Enzymatic resolution has been optimised through variation of the hydrolase biocatalyst and reaction conditions leading to synthetically useful routes to enantiopure cyanohydrin acetates.

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(R)-(−)-Acetoxy-3,4,5-trimethoxyphenylacetonitrileC13H15NO5[α]D20=-9.7 (c 3.0, CHCl3)>99% eeSource of chirality: enzymatic hydrolysisAbsolute configuration: (R)

(R)-(+)-Acetoxy-2-bromophenylacetonitrileC10H8BrNO2[α]D20=+11.6 (c 3.0, CHCl3)>99% eeSource of chirality: enzymatic hydrolysisAbsolute configuration: (R)

(R)-(+)-Acetoxy-2,5-difluorophenylacetonitrileC10H7F2NO2[α]D20=+17.7 (c 2.8, CHCl3)>99% eeSource of chirality: enzymatic hydrolysisAbsolute configuration: (R)

(S)-(+)-Acetoxy-2-t-butylphenylacetonitrileC14H17NO2[α]D20=+8.9 (Please check the optical rotation value of compound C14H17NO2.c 4.4, CHCl3)>98% eeSource of chirality: enzymatic hydrolysisAbsolute configuration: (S)

(R)-(+)-Acetoxy-2,5-dimethoxyphenylacetonitrileC12H13NO4[α]D20=+17.9 (c 1.7, CHCl3)>99% eeSource of chirality: enzymatic hydrolysisAbsolute configuration: (R)

(R)-(−)-Hydroxy-2-bromophenylacetonitrileC8H6BrNO[α]D20=-13.4 (c 1.1, CHCl3)>99% eeSource of chirality: enzymatic hydrolysisAbsolute configuration: (R)