Access to spirocyclic oxindoles via N-heterocyclic carbene-catalyzed reactions of enals and oxindole-derived α,β-unsaturated imines.
نویسندگان
چکیده
A diastereoselective access to β-lactam fused spirocyclic oxindoles and related compounds bearing all carbon spiro centers is described. This N-heterocyclic carbene-catalyzed process employed challenging β,β-disubstituted α,β-unsaturated imines to react with enals.
منابع مشابه
Highly enantioselective addition of enals to isatin-derived ketimines catalyzed by N-heterocyclic carbenes: synthesis of spirocyclic γ-lactams.
An N-heterocyclic carbene (NHC)-catalyzed annulation reaction of isatin N-Boc ketimines and enals is developed for the synthesis of spirocyclic oxindole-γ-lactams bearing one quaternary chiral center in good yields and excellent stereoselectivities (up to >20:1 dr and 99% ee).
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ورودعنوان ژورنال:
- Organic letters
دوره 14 9 شماره
صفحات -
تاریخ انتشار 2012