title: Synthesis of Chiral γ-Lactams via in Situ Elimination/Iridium-Catalyzed Asymmetric Hydrogenation of Racemic γ-Hydroxy γ-Lactams.
abstract: Chiral γ-lactams have been synthesized in excellent yields and enantioselectivities (up to 99% yield and 96% ee) from easily accessible racemic γ-hydroxy γ-lactams via an iridium-phosphoramidite catalyzed asymmetric hydrogenation. The reaction was designed based on insight into the reaction mechanism demonstrated in previous work and can be carried out at a reduced catalyst loading of 0.1 mol % on a gram scale. Several potential bioactive compounds can be synthesized from the reduced products. Mechanistic studies indicated that the reduced products were obtained via the hydrogenation of the N-acyliminium cations, generated from γ-hydroxy γ-lactams.
authors.affiliation: School of Chemistry and Chemical Engineering, and ‡School of Pharmacy, Shanghai Jiao Tong University , 800 Dongchuan Road, Shanghai 200240, P. R. China.
authors.forename: Qianjia
authors.initials: Q
authors.lastname: Yuan
authors.affiliation: School of Chemistry and Chemical Engineering, and ‡School of Pharmacy, Shanghai Jiao Tong University , 800 Dongchuan Road, Shanghai 200240, P. R. China.
authors.forename: Delong
authors.initials: D
authors.lastname: Liu
authors.affiliation: School of Chemistry and Chemical Engineering, and ‡School of Pharmacy, Shanghai Jiao Tong University , 800 Dongchuan Road, Shanghai 200240, P. R. China.
authors.forename: Wanbin
authors.identifier: 0000-0002-4788-4195
authors.initials: W
authors.lastname: Zhang