Direct Enantioselective Vinylogous Mannich Reaction of Ketimines with γ-Butenolide by Using Cinchona Alkaloid Amide/Zinc(II) Catalysts

• Published in: Chemistry : a European journal Vol. 21; no. 27; pp. 9615 - 9618
• Main Authors: Nakamura, Shuichi, Yamaji, Ryota, Hayashi, Masashi
• Format: Journal Article
• Language: English
• Published: Weinheim WILEY-VCH Verlag 26.06.2015; WILEY‐VCH Verlag; Wiley
• Subjects: 4-Butyrolactone - analogs & derivatives; 4-Butyrolactone - chemical synthesis; 4-Butyrolactone - chemistry; Alkaloids; Amides; asymmetric synthesis; Catalysis; Catalysts; Chemistry; Chemistry, Multidisciplinary; cinchona alkaloids; Cinchona Alkaloids - chemical synthesis; Cinchona Alkaloids - chemistry; Enantiomers; Imines; Imines - chemistry; ketimines; Lewis acids; Mesylates - chemistry; Molecular Structure; Nitriles - chemistry; Physical Sciences; Science & Technology; Stereoisomerism; γ-butenolides; HALF THIOESTERS; gamma-butenolides; ACID; ISOMERIZATION; Lewis acids; ALDEHYDES; (R)-CONVOLUTAMYDINE; cinchona alkaloids; MICHAEL ADDITION; asymmetric synthesis; ketimines; ORGANOCATALYSTS; ALDOL REACTION; BUTYROLACTAM; CONSTRUCTION; γ-butenolides
• ISSN: 0947-6539; 1521-3765
• DOI: 10.1002/chem.201500599

A direct enantioselective vinylogous Mannich reaction of ketimines with γ‐butenolide has been developed. Good yields and enantioselectivities were observed for the reaction of various ketimines by using a cinchona alkaloid amide/Zn(OTf)2 catalyst and Et3N. Both enantiomers of the products could be obtained by using pseudoenantiomeric chiral catalysts. A direct enantioselective vinylogous Mannich reaction of ketimines with γ‐butenolide has been developed. Good yields and enantioselectivities were observed for the reaction of various ketimines by using a cinchona alkaloid amide/Zn(OTf)2 catalyst and Et3N (see scheme; Tf=triflate). Both enantiomers of the products could be obtained by using pseudoenantiomeric chiral catalysts.