Room Temperature, Reductive Alkylation of Activated Methylene Compounds: Carbon–Carbon Bond Formation Driven by the Rhodium-Catalyzed Water–Gas Shift Reaction

The rhodium-catalyzed water–gas shift reaction has been demonstrated to drive the reductive alkylation of several classes of activated methylene compounds at room temperature. Under catalysis by rhodium trichloride (2–3 mol %), carbon monoxide (10 bar), water (2–50 equiv), and triethylamine (2.5–7 equiv), the scope has been successfully expanded to cover a wide range of alkylating agents, including aliphatic and aromatic aldehydes, as well as cyclic ketones, in moderate to high yields. This method is comparable to, and for certain aspects, surpasses the established reductive alkylation protocols.