Highly diastereo- and enantioselective NHC-catalyzed [3+2] annulation of enals and isatins

Chem Commun (Camb). 2011 Sep 28;47(36):10136-8. doi: 10.1039/c1cc13860j. Epub 2011 Aug 9.

Abstract

The chiral N-heterocyclic carbene bearing a proximal hydroxy group derived from L-pyroglutamic acid was found to be an efficient catalyst for the [3+2] annulation of enals and isatins to give the corresponding spirocyclic oxindolo-γ-butyrolactones in good yield with good diastereo- and enantioselectivities.