Substituent Effects on the Enantioselective Hydrocyanation of Aryl Aldehydes

Article abstract of DOI:10.1016/0957-4166(94)80124-X

A detailed study of the dipeptide catalysed enantioselective hydrocyanation of a series of O-substituted 4-hydroxybenzaldehydes has shown that adverse steric effects can occur leading to low enantiomeric excess (e.e.) values when the substituent is long and flexible.Similar hydrocyanation of several derivatives of 3,4-dihydroxybenzaldehydes have been shown to give very variable values of e.e.Hydrocyanation of 3,5-dimethoxy and 3,4,5-trimethoxybenzaldehyde consistently gave low values of e.e.