The hydrogenation of molecules with polar bonds catalyzed by a ruthenium(II) complex bearing a chelating N-heterocyclic carbene with a primary amine donor

Abstract

The complex [RuCp*(C-NH(2))(py)]PF(6) bearing a chelating N-heterocyclic carbene with an NH(2) group (C-NH(2)) is an active catalyst for the H(2)-hydrogenation of ketones, an epoxide, ester and ketimine in basic solution. A maximum turnover frequency of 17,600 h(-1) is achieved under mild reaction conditions (25 °C) and economical use of hydrogen (8 bar) while the TOF of a related complex with a phosphine-amine ligand is much smaller.