Bronsted acid catalysis of achiral enamine for regio- and enantioselective nitroso aldol synthesis.
Two types of chiral Brønsted acid catalysts have been shown to catalyze regio- and enantioselective nitroso aldol synthesis between nitrosobenzene and achiral enamine. The combination of Brønsted acidity and amine moiety of enamine realizes complete regioselectivity with high enantioselectivity. After a survey of Brønsted acid catalysts, 1-naphthyl glycolic acid is found to be optimal in the O-nitroso aldol pathway, while 1-naphthyl TADDOL is the best catalyst for the N-nitroso aldol pathway. This is based on our finding on the control of regioselectivity by changing the amine moiety of enamine and the choice of Brønsted acidity.
Momiyama
Norie
N
Department of Chemistry, The University of Chicago, 5735 South Ellis Avenue, Chicago, Illinois 60637, USA.
Yamamoto
Hisashi
H
D000447:Aldehydes / Q000138:chemical synthesis*; D000588:Amines / Q000737:chemistry*; D002384:Catalysis; D006863:Hydrogen-Ion Concentration; D009603:Nitroso Compounds / Q000138:chemical synthesis*; D013237:Stereoisomerism
D000447:Aldehydes; D000588:Amines; D009603:Nitroso Compounds