Highly enantioselective Pd-catalyzed asymmetric hydrogenation of activated imines.
Pd/bisphosphines complexes are highly effective catalysts for asymmetric hydrogenation of activated imines in trifluoroethanol. The asymmetric hydrogenation of N-diphenylphosphinyl ketimines 3 with Pd(CF3CO2)/(S)-SegPhos indicated 87-99% ee, and N-tosylimines 5 could gave 88-97% ee with Pd(CF3CO2)/(S)-SynPhos as a catalyst. Cyclic N-sulfonylimines 7 and 11 were hydrogenated to afford the useful chiral sultam derivatives in 79-93% ee, which are important organic synthetic intermediates and structural units of agricultural and pharmaceutical agents.
Wang
You-Qing
YQ
Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China.
Lu
Sheng-Mei
SM
Zhou
Yong-Gui
YG