Ligand-Controlled Copper(I)-Catalyzed Cross-Coupling of Secondary and Primary Alcohols to α-Alkylated Ketones, Pyridines, and Quinolines.

One hexanuclear Cu(I) cluster of 4,6-dimethylpyrimidine-2-thiolate efficiently catalyzes the dehydrogenative cross-coupling of secondary and primary alcohols to α-alkylated ketones with high selectivity. This transformation proceeds through a one-pot sequence of dehydrogenation of alcohols, condensation of aldehydes and ketones, hydrogenation of the resulting α,β-unsaturated ketones, and dehydrogenation of the α-alkylated alcohols to generate α-alkylated ketones. This catalytic system also displays high activity for the annulation reaction of secondary alcohols with γ-amino- and 2-aminobenzyl alcohols to yield pyridines and quinolines, respectively.