Tandem Aryne Sequence Route to the Synthesis of Substituted Fluorenones

Abstract

Substituted m-terphenyl carboxylic acids of the type 1a–e were prepared by the tandem aryne sequence from substituted dihaloiodobenzenes with arylmagnesium bromide followed by quenching with CO₂. The carboxylic acids 1a–e were converted into fluorenones 2a–e using either H₂SO₄ in CH₃OH or PPA.