Supramolecular Chiral Organic Ion Pair Catalyst

Significance

A chiral organic ion pair catalyst consisting of a chiral tetraaminophosphonium cation, two phenols, and a phenoxide anion is reported. The components self-assemble through intermolecular hydrogen bonds to a ten-membered cyclic network 1 whose structure could be determined in the solid state by single crystal Röntgen analysis. The well-defined molecular assembly was used as catalyst in a highly stereoselective conjugate addition of azlactone 2 to α,β-unsaturated ester surrogates 3.