Organocatalytic activation of alkylacetic esters as enolate precursors to react with α,β-unsaturated imines.
نویسندگان
چکیده
Asymmetric functionalization of alkylacetic esters and their derivatives is traditionally achieved via preformed enolates with chiral auxiliaries. Catalytic versions of such transformations are attractive but challenging. A direct catalytic activation of simple alkylacetic esters via N-heterocyclic carbene organocatalysts to generate chiral enolate intermediates for highly enantioselective reactions is reported.
منابع مشابه
Asymmetric access to the smallest enolate intermediate via organocatalytic activation of acetic ester.
An NHC-catalyzed activation of acetic esters to afford enolate intermediates is disclosed. The catalytically generated triazolium enolate intermediates serve as two-carbon nucleophiles that undergo highly enantioselective reactions with enones and α,β-unsaturated imines to give α-unsubstituted δ-lactones and lactams, respectively.
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عنوان ژورنال:
- Organic letters
دوره 15 19 شماره
صفحات -
تاریخ انتشار 2013