Rhodium(III) NCN pincer complexes catalyzed transfer hydrogenation of ketones

Abstract

Air-stable monomeric rhodium(III) NCN pincer complexes were synthesized via direct C-H bond activation of 1,3-bis(2-pyridyloxy)benzene, 3,5-bis(2-pyridyloxy)toluene and 3,5-bis(2-pyridyloxy)anisole with RhCl3 center dot 3H(2)O in ethanol under reflux. The synthesized complexes were characterized by elemental analysis and H-1 NMR. One of the complexes was structurally characterized by X-ray analysis. An investigation into the catalytic activity of the complex 1a as catalyst for transfer hydrogenation of ketones to alcohols at 82 degrees C in the presence of iPrOH/KOH was undertaken with the conversions up to 99%. (C) 2009 Elsevier Ltd. All rights reserved.