Cobalt-mediated, enantioselective synthesis of C(2) and C(1) dienes.
نویسندگان
چکیده
The asymmetric C-H functionalization of norbornene and norbornadiene with five-, six-, and seven-membered cyclic enones mediated by the reactive intermediate [{η(5)-((t)BuMe(2)Si)C(5)H(4)}Co(NO)(2)] is reported. A novel base mixture derived from enantiopure ammonium salts and NaHMDS was used as a source of chirality, and this enantioselective desymmetrization of C(s) alkenes has been applied to the asymmetric synthesis of C(2)- and C(1)-symmetric diene ligands in high regioselectivity (3.7-20:1 anti/syn), near perfect diastereoselectivity (>99:1 dr), and high enantioselectivity (90-96% ee).
منابع مشابه
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عنوان ژورنال:
- Journal of the American Chemical Society
دوره 132 46 شماره
صفحات -
تاریخ انتشار 2010