Construction of CF3-Functionalized Fully Substituted Benzonitriles through Rauhut-Currier Reaction Initiated [3 + 3] Benzannulation

J Org Chem. 2021 Nov 5;86(21):14844-14854. doi: 10.1021/acs.joc.1c01631. Epub 2021 Oct 1.

Abstract

Though numerous cyanation reactions have been developed for the synthesis of benzonitriles, the construction of valuable fully substituted benzonitriles is still a challenging task. Herein, we reported a tertiary amine-catalyzed [3 + 3]-benzannulation for the green synthesis of CF3-functionalized fully substituted benzonitriles. This strategy features exclusive chemoselectivity, high atom-economy, and good step-economy with environment-friendly reagents and mild conditions. Unique triphenyl-substituted dicyanobenzoate products could be rapidly constructed using this method. The practicality and reliability of this reaction were proved by the successful scale-up synthesis. A mechanistic study indicates that the [3 + 3]-benzannulation was initiated by an intermolecular Rauhut-Currier reaction.