Dicyanoketene Acetals, a Novel Type of ?-Acid Catalyst for Monothioacetalization of Acetals

Article abstract of DOI:10.1016/0040-4039(94)80022-7

Dicyanoketene acetals such as dicyanoketene dimethyl acetal and ethylene acetal are introduced to be a novel type of ?-acid catalyst for the monothioacetalization of acetals.Particularly, the catalytic activity of dicyanoketene ethylene acetal was found to be superior to that of tetracyanoethylene and chemoselective in the crossover reaction of the monothioacetalization of a ketone-, an aldehyde-acetal and an alcohol THP-ether providing a ketone monothioacetal favorably.