Substituierte halogenocarbonylmetallate des chroms,molybdäns und wolframs : III. Ligandensubstitution an halogenocarbonylmetallaten der VI. Nebengruppe

The halopentacarbonylmetal compounds of molybdenum and tungsten react with phosphines in polar aprotic solvents with CO substitution to give the ionic derivatives LM(CO)₄X]^? (X = Cl, Br; M = Mo, W; L = i-Pr_nPh_3?nP, (Me₂N)_nPh_3?nP, (i-PrO)_nPh_3?nP, Ph₂MeP, Et₃P, (PhO)₃P, n = 0, 1, 2, 3). The substitution of the halide ligand, which is catalysed by protic solvents, provides a convenient route to the neutral complexes LM(CO)₅ and LL′M(CO)₄ (L = phosphines; L′ = ammonia, acetonitrile, pyridine, piperidine). cis-(NH₃)(i-Pr₃P)W(CO)₄ in solution is slowly deuterated by D₂O. In this reaction all three hydrogen atoms appear to be exchanged simultaneously.