Rhodium(III) complexes of N-{2-(arylseleno/telluro)ethyl} morpholine: Synthesis, structure and applications as efficient catalyst for transfer hydrogenation reaction of ketones

N-{2-(Arylseleno/telluro)ethyl}morpholine (L1/L2) synthesized by reacting PhSe-/ArTe- (generated insitu) with (2-chloroethyl)morpholine hydrochloride, reacts with RhCl3 center dot 3H(2)O resulting in complexes [RhCl2(L1/L2)(4)][ClO4] (1/2). H-1, C-13{H-1} and Se-77{H-1}/Te-125{H-1} NMR spectra of L1, L2, 1 and 2 were found characteristic. The single crystal structure of 2 has been solved. The L2 binds with Rh in 2 as a monodentate ligand. The geometry around Rh is distorted octahedral. The Rh-Te distances are in the range 2.6509(9)-2.6688(8) angstrom . Both the complexes efficiently catalyze transfer hydrogenation reaction of acetophenone (TON/TOF up to 9.9 x 10(4)/9.9 x 10(3) h(-1)) and benzophenone (TON up to 9.8 x 10(4) and TOF up to 9.8 x 10(3) h(-1)). (C) 2010 Elsevier B.V. All rights reserved.