Simple and efficient methods of synthesis of 3,3-diarylcyclobutanone and 3,3-diarylcyclobutylamine derivatives using the TiCl < inf > 4 < /inf > /R < inf > 3 < /inf > N reagent system

Abstract

The iminium ions generated in situ by the oxidation of N,N-diisopropyl-N- benzylamine using iodine react with diaryl ketones in the presence of TiCl 4/R3N to give the corresponding 3,3-diarylcyclobutanones in moderate to good yields (49-86%). The 3,3-diarylcyclobutanone iminium ions formed in this transformation was reduced in situ with B2H 6 to produce the corresponding 3,3-diarylcyclobutylamines (52-79% yields), a class of compounds with potential antidepressant activity. In addition, a series of N,N-dimethyl-3,3-diarylcyclobutylamines were synthesized by the reductive amination of the corresponding 3,3-diarylcyclobutanone derivatives. © 2005 American Chemical Society.