C-C Bond Formation of Benzyl Alcohols and Alkynes Using a Catalytic Amount of KOt Bu: Unusual Regioselectivity through a Radical Mechanism

Angew Chem Int Ed Engl. 2019 Mar 11;58(11):3373-3377. doi: 10.1002/anie.201812687. Epub 2019 Feb 7.

Abstract

We report a C-C bond-forming reaction between benzyl alcohols and alkynes in the presence of a catalytic amount of KOt Bu to form α-alkylated ketones in which the C=O group is located on the side derived from the alcohol. The reaction proceeds under thermal conditions (125 °C) and produces no waste, making the reaction highly atom efficient, environmentally benign, and sustainable. Based on our mechanistic investigations, we propose that the reaction proceeds through radical pathways.

Keywords: alkynes; benzyl alcohols; potassium tert-butoxide; radicals; α-alkylated ketones.