SUBSTITUTED METAL-CARBONYLS .23. SYNTHESES OF UNICOORDINATED DIPHOSPHINE COMPLEXES OF CR AND MO AND THEIR ENTRY INTO HETEROBIMETALLICS M,M'(CO)(10)(MU-P-P) [M,M'=CR,MO,W P-P=PH(2)P(CH2)(N)PPH(2),N=2-4] AS METALLOLIGANDS

A series of pentacarbonyl complexes of chromium and molybdenum with un icoordinated-diphosphines, M(CO)(5)(eta(1)-P-P) (P-P = dppe, dppp, dpp b) has been prepared by amine oxide-induced phosphine substitution the binary carbonyls. The basicity of the pendant phosphine groups was de monstrated by their ready conversion to the diphosphine-bridged hetero bimetallic complexes (OC)(5)M(mu-P-P)M'(CO)(5) (M,M' = Cr, Mo, W; M no t equal M') in the presence of M'(CO)(5)(CH3CN). The complexes were ch aracterized by IR and NMR (H-1 and (31)p-{H-1}) spectroscopy.