Highly enantioselective addition of enals to isatin-derived ketimines catalyzed by N-heterocyclic carbenes: synthesis of spirocyclic γ-lactams.

Org Lett

Division of Chemistry & Biological Chemistry, School of Physical & Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore.

Published: November 2012

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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http://dx.doi.org/10.1021/ol302475gDOI Listing

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