title: Dual Lewis acid-Lewis base activation in enantioselective cyanation of aldehydes using acetyl cyanide and cyanoformate as cyanide sources.
abstract: Dual activation by a chiral Lewis acid and an achiral or chiral Lewis base enabled cyanation of both aromatic and aliphatic aldehydes with acetyl cyanide and ethyl cyanoformate to provide direct access to O-acetylated and O-alkoxycarbonylated cyanohydrins, respectively, under mild conditions. With a combination of a Ti-salen catalyst and Et3N, benzaldehyde was converted to the O-acetylated cyanohydrin with 94% ee within 10 h at -40 degrees C in 89% isolated yield.
authors.affiliation: Department of Chemistry, Organic Chemistry, Royal Institute of Technology, SE 100 44 Stockholm, Sweden.
authors.forename: Stina
authors.initials: S
authors.lastname: Lundgren
authors.forename: Erica
authors.initials: E
authors.lastname: Wingstrand
authors.forename: Maël
authors.initials: M
authors.lastname: Penhoat
authors.forename: Christina
authors.initials: C
authors.lastname: Moberg
mesh_terms: D000447:Aldehydes / Q000138:chemical synthesis* / Q000737:chemistry; D003486:Cyanides / Q000737:chemistry*; D015394:Molecular Structure; D009570:Nitriles / Q000138:chemical synthesis / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D000447:Aldehydes; D003486:Cyanides; D009570:Nitriles