for the synthesis of 0-substituted cyanohydrins from aldehydes and ketones, in the absence of solvent, employing minimum amounts of the corresponding cyanides has been optimised. Aldehydes react more rapidly than ketones using triethylamine as catalyst offering in both cases almost quantitative yields of the corresponding O-trimethylsilyl, O-methoxycarbonyl, O-benzoyl and O-acetyl cyanohydrins.
Cyanobenzoylation and Hydrocyanation of Aldehydes with Benzoyl Cyanide Using No Catalyst
作者:Tsutomu Watahiki、Sayoko Ohba、Takeshi Oriyama
DOI:10.1021/ol0348295
日期:2003.7.1
[reaction: see text] In the presence of MS 4A in DMSO, cyanobenzoylation of various aldehydes with benzoylcyanide proceeded very smoothly to give the corresponding cyanohydrin benzoates in high to excellent yields without an acid or a base. On the other hand, reaction of aldehydes with BzCN in DMSO-H(2)O also occurred readily to afford the corresponding free cyanohydrins exclusively.