title: Enantioselective organocatalytic Michael addition of ketones to alkylidene malonates.
abstract: Organocatalysts bearing sulfide or sulfone functions (1a-d) were studied for the direct asymmetric Michael addition of ketones and alkylidene malonates. The organocatalyst (S)-2-((naphthalen-2-ylthio)methyl)pyrrolidine, bearing a pyrrolidine and a sulfide moiety, showed a very high catalytic activity in the absence of additives. The reaction condition is mild, and the Michael adducts were obtained in very good enantioselectivities (up to 96%), diastereoselectivities (up to 95:5), and chemical yields (up to 95%).
authors.affiliation: Department of Chemistry, National Taiwan Normal University, Taipei, Republic of China.
authors.forename: Siang-En
authors.initials: SE
authors.lastname: Syu
authors.forename: Chan-Hui
authors.initials: CH
authors.lastname: Huang
authors.forename: Ko-Wei
authors.initials: KW
authors.lastname: Chen
authors.forename: Chia-Jui
authors.initials: CJ
authors.lastname: Lee
authors.forename: Utpal
authors.initials: U
authors.lastname: Das
authors.forename: Yeong-Jiunn
authors.initials: YJ
authors.lastname: Jang
authors.forename: Wenwei
authors.initials: W
authors.lastname: Lin
mesh_terms: D002384:Catalysis; D007659:Ketones / Q000737:chemistry*; D008314:Malonates / Q000737:chemistry*; D011759:Pyrrolidines / Q000737:chemistry*; D013237:Stereoisomerism; D013379:Substrate Specificity; D013440:Sulfides / Q000737:chemistry*
chemical_list: D007659:Ketones; D008314:Malonates; D011759:Pyrrolidines; D013440:Sulfides; C030290:malonic acid; C032519:pyrrolidine