One-Pot Synthesis of Multiarylated Benzophenones via [3 + 2 + 1] Benzannulation of Ketones, Alkynes, and α,ß-Unsaturated Carbonyls.

In this study, we synthesized γ-phenyl-ß,γ-unsaturated ketones in situ from acetophenones and phenylacetylenes under Trofimov's conditions using KOtBu in a dimethyl sulfoxide (DMSO) solvent. The obtained ketones reacted with α,ß-unsaturated carbonyls in a one-pot manner, forming tri- or diarylated benzophenones. The present reaction proceeded efficiently by one-pot manipulation with a suitable carboxylic acid.