MIXED CARBONYL-ALKYL ISOCYANIDE COMPLEXES OF MOLYBDENUM

Article abstract of DOI:10.1016/S0022-328X(00)83011-9

The synthesis of complexes of the type Mo(CO)2(CNR)2(PR3)2 (R=CH3, CMe3 or C6H11 and PR3=PEt3, PPr3ⁿ, PMePh2 or PEtPh2) has been accomplished by the reaction of (η³-C3H5)Mo(CO)2(CNR)2Cl with slightly more than two equivalents of PR3.The stereochemistry of these complexes has been deduced from IR and 1H, 13C and 31P NMR measurements.When RNC is reacted with (η³-C3H5)Mo(CO)2(CNR)2Cl in the presence of a small amount of PMePh2, the complexes cis-Mo(CO)2(CNR)4 are formed in 20-25percent yield together with <(η³-C3H5)Mo(CO)(CNR)4>⁺ (R=CMe3 or C6H11).The latter cations have been isolated as their B(C6H5)4^- salts.The formation of cis-Mo(CO)2(CNR)4 under these conditions supports the proposal that the phosphine-assisted allyl chloride elimination is an important mechanism in the reactions of phosphines with derivatives of the type (η³-C3H5)Mo(CO)2L2Cl.The X-ray photoelectron spectra of certain complexes of the types Mo(CO)2(CNR)2(PR3)2 and cis-Mo(CO)2(CNR)4 have been recorded and the results are discussed briefly.