Phosphine-Free NNN-Manganese Complex Catalyzed α-Alkylation of Ketones with Primary Alcohols and Friedlander Quinoline Synthesis

Herein, we report a very simple and inexpensive catalytic system based on Earth's abundant transition metal manganese and on a bench-stable phosphine-free NNN-pincer ligand for an atom-efficient alpha-alkylations of ketones with primary alcohols via hydrogen-autotransfer C-C bond formation protocol. The precatalyst could be generated insitu and could be activated by using catalytic amount of base under milder conditions. A range of ketones were efficiently diversified with a broad range of primary alcohols in good to excellent isolated yields. Remarkably, this catalyst could also be employed for the synthesis of quinoline derivatives using 2-aminobenzyl alcohol as an alkylating agent. The later reaction is highly benign producing only hydrogen and water as byproducts.