Catalytic carbon insertion into the β-vinyl C-H bond of cyclic enones with alkyl diazoacetates.
نویسندگان
چکیده
The first example of the boron Lewis acid catalyzed C(sp2)-H functionalization of cyclic enones was achieved using diazoacetates. The insertion of the carbon atom of diazoacetates utilizes BF3•Et2O or a newly designed oxazaborolidinium ion as a catalyst to afford β-functionalized cyclic enones from simple cyclic enones in a single step and high yields. The reaction mechanism was investigated with deuterium labeled 2-cyclohexen-1-one.
منابع مشابه
Catalytic enantioselective carbon insertion into the β-vinyl C-H bond of cyclic enones.
Chiral oxazaborolidinium ion-catalyzed Csp(2)-H functionalization of enones using diazoacetate has been developed. Various β-substituted cyclic enones were synthesized in high yield (up to 99%) with high to excellent enantioselectivity (up to 99% ee). The synthetic utility of this reaction was demonstrated by the formal synthesis of (+)-epijuvabione.
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ورودعنوان ژورنال:
- Organic letters
دوره 15 7 شماره
صفحات -
تاریخ انتشار 2013