Organocatalytic Synthesis of α-Triphenylmethylamines from Diarylketimines and Phenols.

A formal Betti reaction between variously substituted phenols and benzophenone-derived imines to afford α-triphenylmethylamines is reported. The key to the success of this transformation is the generation of the reactive benzophenone iminium species under organocatalytic conditions. Different phenols reacted smoothly, enabling the synthesis of an array of α-triphenylmethylamines, which are highly valued structural motifs in bioactive molecules and chemical sensors.