PmHNL catalyzed synthesis of (R)-cyanohydrins derived from aliphatic aldehydes

Hydroxynitrile lyase from the Japanese apricot (Prunus mume) catalyzes the formation of several aliphatic cyanohydrins in an asymmetric fashion. By employing a biphasic reaction system, aliphatic aldehydes with various structural features can be converted to the corresponding (R)-cyanohydrins with good overall yield and enantiomeric excess.

A series of saturated, unsaturated, and cyclic aliphatic aldehydes were subjected to (R)-HNL (Prunus mume) catalyzed asymmetric cyanohydrin synthesis.Figure optionsDownload as PowerPoint slide

(2R,3E,5E)-2-Hydroxy-3,5-octadienenitrileC8H11ONEe = 97%[α]D25=-31.1 (c 1.4, CHCl3)Source of chirality: asymmetric hydrocyanationAbsolute configuration: 2R

(2R)-2-Cyclobutyl-2-hydroxyacetonitrileC6H9ONEe = 92%[α]D25=+3.8 (c 1.1, CHCl3)Source of chirality: asymmetric hydrocyanationAbsolute configuration: 2R

(2R)-2-Cyclopentyl-2-hydroxyacetonitrileC7H11ONEe = 94%[α]D25=+11.2 (c 1.0, CHCl3)Source of chirality: asymmetric hydrocyanationAbsolute configuration: 2R

(2R)-2-Cyclohexenyl-2-hydroxyacetonitrileC8H11ONEe = 90%[α]D25=-16.7 (c 1.5, CHCl3)Source of chirality: asymmetric hydrocyanationAbsolute configuration: 2R

(2R)-2-Hydroxy-2-(6,6-dimethylbicyclo[3.1.1]hept-2-en-3-yl)acetonitrileC11H15ONEe = 99%[α]D25=-21.1 (c 1.4, CHCl3)Source of chirality: asymmetric hydrocyanationAbsolute configuration: 2R

(2R,3E)-3-Ethyl-2-hydroxy-3-pentenenitrileC7H11ONEe = 92%[α]D25=-32.1 (c 1.0, CHCl3)Source of chirality: asymmetric hydrocyanationAbsolute configuration: 2R

(2R,3E)-2-Hydroxy-3-octenenitrileC8H13ONEe = 72%[α]D25=-16.3 (c 1.0, CHCl3)Source of chirality: asymmetric hydrocyanationAbsolute configuration: 2R

(2R,3E)-2-Hydroxy-3-methyl-3-hexenenitrileC7H11ONEe = 96%[α]D25=-26.8 (c 1.2, CHCl3)Source of chirality: asymmetric hydrocyanationAbsolute configuration: 2R

(2R,3E)-3-Ethyl-2-hydroxy-3-heptenenitrileC9H15ONEe = 92%[α]D25=-36.8 (c 1.0, CHCl3)Source of chirality: asymmetric hydrocyanationAbsolute configuration: 2R