Enantioselective formation of cyclopropane spiroindenes from benzofulvenes by phase transfer catalysis

Chem Commun (Camb). 2016 Oct 13;52(84):12474-12477. doi: 10.1039/c6cc07170h.

Abstract

The enantio- and diastereoselective formation of indenes spirofused to highly substituted cyclopropanes is described. The application of a new cinchona alkaloid derived ammonium salt in a phase transfer catalysis setup facilitates high selectivity and excellent yields at low catalyst loadings (0.1-1.0 mol%).