Acceleration of ruthenium(II)- and rhodium(I)-catalyzed hydrogen-transfer reaction by rare earth metal triflates

The addition of Yb(OTf)(3) as an additive considerably accelerates the RuCl2(PPh3)(3)- and RhCl(PPh3)(3)-catalyzed hydrogen-transfer reduction of both aromatic and aliphatic ketones in which Ru:Yb ratios of 1:2-1:4 are critically important for achieving acceleration. (C) 2001 Elsevier Science Ltd. All rights reserved.