Homogeneous hydrogenation with new cationic ruthenium(II) complexes of [RuH(CO)(NCCH3)(PPh(3))(2)(diphos)](+) and [RuH(CO)(NCCH3)(PPh(3))(diphos)](+). Crystal structure of [RuH(CO)(NCCH3)(PPh(3))(Fe(eta(5)-C(5)H(4)PPh(2))(2))][BF4]

Abstract

A series of ruthenium(II) complexes [RuH(CO)(NCCH3)(PPh(3))(2)(diphos)][BF4] (diphos: = dppm, Ph(2)PCH(2)PPh(2) (2); dppe = Ph(2)PCH(2)CH(2)PPh(2) (3); = dppp, Ph(2)PCH(2) CH(2)CH(2)PPh(2) (4); = dppb, Ph(2)PCH(2)CH(2)CH(2)CH(2)PPh(2) (5)) and [RuH(CO)(NCCH3) (PPh(3))(diphos)][BF4] (diphos: = dppe (6); = dppp (7); = dppb (8); = dppf, Fe(eta(5)-C(5)H(4)PPh(2))(2) (9)) was prepared from the reaction of [RuH(CO)(NCCH3)(2)(PPh(3))(2)][BF4] and diphos ligands by changing the reaction conditions. These complexes have been characterized by analytical and spectroscopic (IR and H-1 NMR) methods. The structure of [RuH(CO)(NCCH3)(PPh(3))(dppf)][BF4] (9) has been determined by X-ray crystallography. The homogeneous hydrogenations of propanal to propan-l-ol catalyzed by complexes 2-9 have been investigated at 90 degrees C and 20 atm hydrogen pressure. The catalytic activities of the chelating diphosphine species 6-9 were dependent upon the structure of the complex as well as upon the ring sizes of the chelates. Copyright (C) 1996 Elsevier Science Ltd