Jacob P. MacDonald, Benjamin H. Shupe, John D. Schreiber and Annaliese K. Franz
Chem. Commun., 2014,50, 5242-5244
DOI:
10.1039/C3CC47767C,
Communication
A Lewis acid-catalyzed stereoselective [3+2] annulation of crotylsilanes with iminooxindoles is reported to access 2,3′-pyrrolidinyl spirooxindoles with four stereocenters. The addition of NaBArF significantly enhances reactivity, allowing either metal salts or acidic clay to be effective catalysts for the stereoselective reaction.