Efficient β-alkylation of secondary alcohols to α-substituted ketones catalyzed by functionalized Ir complexes via borrowing hydrogen in water

Abstract

The borrowing hydrogen reaction of alcohols is a green synthetic approach for C–C bond construction, while the selective formation of α-substituted ketones from alcohols in water is highly challenging. Herein, we report an efficient and highly selective β-alkylation of secondary alcohols to α-substituted ketones catalyzed by an amidato Ir(III) complex in water via the borrowing hydrogen strategy. Catalyst 1d bearing a strong electron-donating hydroxyl group on the ligand provided the ketone products with high yields up to 99%. A broad range of substrates, including various aromatic and aliphatic alcohol substrates, were well tolerated under the optimized conditions. Based on control experiments and in situ FT-IR experiments, a plausible mechanism was proposed.