title: Highly enantio- and diastereoselective Brassard type hetero-Diels-Alder approach to 5-methyl-containing alpha,beta-unsaturated delta-lactones.
abstract: Two efficient new chiral copper (II) Schiff base complexes were developed for the highly enantio- and diastereoselective HDA reaction of Brassard type diene 1b with aldehydes, to afford the corresponding 5-methyl-containing alpha,beta-unsaturated delta-lactone derivatives in moderate yields, high enantioselectivities (up to 99% ee) and excellent diastereoselectivities (up to 99:1 anti/syn). On the basis of the absolute configuration of 4a-4j disclosed by X-ray diffraction and CD analysis, a possible transition-state model for the enantio- and diastereoselective catalytic reaction has been proposed.
authors.affiliation: Key Laboratory of Green Chemistry and Technology (Sichuan University), Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China.
authors.forename: Lili
authors.initials: L
authors.lastname: Lin
authors.forename: Qian
authors.initials: Q
authors.lastname: Fan
authors.forename: Bo
authors.initials: B
authors.lastname: Qin
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Feng
mesh_terms: D007783:Lactones / Q000138:chemical synthesis*; D008958:Models, Molecular; D015394:Molecular Structure
chemical_list: D007783:Lactones