title: Organocatalytic enantioselective Michael-Michael-Michael-aldol condensation reactions: control of five stereocenters in a quadruple-cascade asymmetric synthesis of highly functionalized hexahydrophenanthrenes.
abstract: A cascade organocatalysis has been developed for the enantioselective synthesis of a highly functionalized hexahydrophenanthrene-2-carbaldehyde containing five contiguous stereogenic centers with high diastereoselectivity and high enantioselectivity (>99% ee). The one-pot method comprises a cascade of organocatalytic Michael-Michael-Michael-aldol reactions of 2-methyl-1,5-dinitro-3-((E)-2-nitrovinyl)benzene and α,β-unsaturated aldehydes (e.g., cinnamaldehyde). The structure and absolute configuration of a product were confirmed by X-ray analysis of an appropriate derivative.
authors.affiliation: Department of Chemistry and Biochemistry, National Chung Cheng University , Chia-Yi, 621, Taiwan, R.O.C.
authors.forename: Arun
authors.initials: A
authors.lastname: Raja
authors.forename: Bor-Cherng
authors.initials: BC
authors.lastname: Hong
authors.forename: Gene-Hsiang
authors.initials: GH
authors.lastname: Lee