title: Catalytic asymmetric synthesis of alpha-alkylidene-beta-hydroxy esters via dynamic kinetic asymmetric transformation involving Ba-catalyzed direct aldol reaction.
abstract: A Ba-catalyzed dynamic kinetic asymmetric transformation (DYKAT) involving a direct aldol/retro-aldol reaction of beta,gamma-unsaturated ester donors is described. A Ba(O-iPr)(2)/BINOL complex promoted the direct aldol reaction/isomerization sequence, and alpha-alkylidene-beta-hydroxy esters were obtained from aryl, heteroaryl, alkenyl, and alkyl aldehydes under simple proton-transfer conditions with 99-87% ee and >20:1 to 15:1 alpha/gamma selectivity.
authors.affiliation: Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
authors.forename: Akitake
authors.initials: A
authors.lastname: Yamaguchi
authors.forename: Shigeki
authors.initials: S
authors.lastname: Matsunaga
authors.forename: Masakatsu
authors.initials: M
authors.lastname: Shibasaki
mesh_terms: D000447:Aldehydes / Q000737:chemistry*; D001464:Barium / Q000737:chemistry*; D002384:Catalysis; D004952:Esters / Q000138:chemical synthesis*; D007536:Isomerism; D007700:Kinetics
chemical_list: D000447:Aldehydes; D004952:Esters; D001464:Barium; C116609:3-hydroxybutanal