title: 9-Amino-(9-deoxy)cinchona alkaloid-derived new chiral phase-transfer catalysts.
abstract: A new class of 9-amino-(9-deoxy)cinchona alkaloid-derived chiral phase-transfer catalysts bearing amino groups was developed by using known cinchona alkaloids as the starting materials. Due to the transformation of the 9-hydroxyl group into a 9-amino functional group, the catalytic performances were significantly improved in comparison with the corresponding first generation phase-transfer catalysts, and excellent yields (92-99%) and high enantioselectivities (87-96% ee) were achieved in the benchmark asymmetric α-alkylation of glycine Schiff base. Based on the special contribution of the amino group to the high yield and enantioselectivity, the possible catalytic mechanism was conjectured.
authors.affiliation: College of Chemistry and Chemical Engineering, Southwest University, Chongqing, 400715, P. R. China. zcj123@swu.edu.cn.
authors.forename: Wenwen
authors.initials: W
authors.lastname: Peng
authors.forename: Jingwei
authors.initials: J
authors.lastname: Wan
authors.forename: Bing
authors.initials: B
authors.lastname: Xie
authors.forename: Xuebing
authors.initials: X
authors.lastname: Ma
mesh_terms: D002384:Catalysis; D002930:Cinchona Alkaloids / Q000138:chemical synthesis / Q000737:chemistry*; D026121:Indole Alkaloids / Q000138:chemical synthesis / Q000737:chemistry*; D015394:Molecular Structure; D044367:Phase Transition; D011812:Quinuclidines / Q000138:chemical synthesis / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D002930:Cinchona Alkaloids; D026121:Indole Alkaloids; D011812:Quinuclidines