title: Catalytic anomeric aminoalkynylation of unprotected aldoses.
abstract: A copper(I)-catalyzed anomeric aminoalkynylation reaction of unprotected aldoses was realized. Use of an electron-deficient phosphine ligand, boric acid to stabilize the iminium intermediate, and a protic additive (IPA) to presumably enhance reversible carbohydrate-boron complexation were all essential for efficient conversion. The reaction proceeded well even with a natural disaccharide substrate, suggesting that the developed catalytic reaction could be useful for the synthesis of glycoconjugates with minimum use of protecting groups.
authors.affiliation: Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
authors.forename: Yasuaki
authors.initials: Y
authors.lastname: Kimura
authors.forename: Soichi
authors.initials: S
authors.lastname: Ito
authors.forename: Yohei
authors.initials: Y
authors.lastname: Shimizu
authors.forename: Motomu
authors.initials: M
authors.lastname: Kanai
mesh_terms: D000480:Alkynes / Q000737:chemistry*; D001896:Boron Compounds / Q000737:chemistry*; D002241:Carbohydrates / Q000737:chemistry*; D002384:Catalysis; D003300:Copper / Q000737:chemistry*; D004187:Disaccharides / Q000737:chemistry*; D004583:Electrons; D006001:Glycoconjugates / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: D000480:Alkynes; D001896:Boron Compounds; D002241:Carbohydrates; D004187:Disaccharides; D006001:Glycoconjugates; D003300:Copper