SpinPhox/iridium(I)-catalyzed asymmetric hydrogenation of cyclic α-alkylidene carbonyl compounds.
Optically active medium-sized cyclic carbonyl compounds bearing an α-chiral carbon center are of interest in pharmaceutical sciences and asymmetric synthesis. Herein, SpinPhox/Ir(I) catalysts have been demonstrated to be highly enantioselective in the asymmetric hydrogenation of the CC bonds in the exocyclic α,β-unsaturated cyclic carbonyls, including a broad range of α-alkylidene lactams, unsaturated cyclic ketones, and lactones. It is noteworthy that the procedure can be successfully used in the asymmetric hydrogenation of the challenging α-alkylidenelactam substrates with six- or seven-membered rings, thus affording the corresponding optically active carbonyl compounds with an α-chiral carbon center in generally excellent enantiomeric excesses (up to 98 % ee). Synthetic utility of the protocol has also been demonstrated in the asymmetric synthesis of the anti-inflammatory drug loxoprofen and its analogue, as well as biologically important ε-aminocaproic acid derivatives.
State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032 (P.R. China).
Xu
X
Liu
Zhaobin
Z
Han
Zheng
Z
Wang
Kuiling
K
Ding
D002384:Catalysis; D056831:Coordination Complexes / Q000737:chemistry*; D006865:Hydrogenation; D007495:Iridium / Q000737:chemistry*; D007769:Lactams / Q000138:chemical synthesis* / Q000737:chemistry; D010720:Phosphines / Q000737:chemistry; D013237:Stereoisomerism
D056831:Coordination Complexes; D007769:Lactams; D010720:Phosphines; D007495:Iridium
asymmetric catalysis; hydrogenation; iridium; lactams; synthesis design