Manganese-Catalyzed beta-Alkylation of Secondary Alcohols with Primary Alcohols under Phosphine-Free Conditions

Manganese(I) complexes bearing a pyridyl-supported pyrazolyl-imidazolyl ligand efficiently catalyzed the direct beta-alkylation of secondary alcohols with primary alcohols under phosphine-free conditions. The beta-alkylated secondary alcohols were obtained in moderate to good yields with water formed as the byproduct through a borrowing hydrogen pathway. beta-Alkylation of cholesterols was also effectively achieved. The present protocol provides a concise atom-economical method for CC bond formation from primary and secondary alcohols.