Highly enantioselective Pd-catalyzed asymmetric hydrogenation of activated imines.
نویسندگان
چکیده
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.
منابع مشابه
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عنوان ژورنال:
- The Journal of organic chemistry
دوره 72 10 شماره
صفحات -
تاریخ انتشار 2007