Rapid Generation of 2-Acyl-4-phenyltetralones from 1,1-Diacylphenylcyclopropanes

Abstract

A rapid and facile method of accessing 4-phenyl-β-keto-α-tetralones is reported. The key homo-Nazarov cyclization was achieved via treatment of the preceding phenylcyclopropane with TiCl4 at below ambient temperatures. In contrast to previous work, which was limited to electron-rich substrates, the present transformations proceeded without heating and were applicable to an electronically broad range of substrates. Furthermore, a mechanistically novel reaction afforded an unexpected γ-diarylketone as well as a rearranged regioisomer of the expected α-tetralone.