SUBSTITUTION-REACTIONS OF CPW(2)(CO)(7)(MU-PPH(2)) WITH DIPHOSPHINE LIGANDS

The known complex CpW(2)(CO)(7)(mu-PPh(2)) (1) has been prepared in go od yield from the reaction of CpW(CO)(3)(PPh(2)) and W(CO)(4)(NCMe)(2) . Compound 1 reacts with the diphosphines PPh(2)XPPh(2) (2-5 for X = C H2, C2H4, C3H7, and (C5H4)(2)Fe, respectively) to produce CpW(2)(CO)(6 )(mu-PPh(2))(eta(1)-(PPh(2))(2)X) (2a, 3a, 4a, and 5a), CpW(2)(CO)(5)( mu-PPh(2))(eta(2)-(PPh(2))(2)X) (2b, 3b, and 4b), and (CO)(6)(mu-PPh(2 ))](2)(eta(1),eta(1)-(PPh(2))(2)X) (3c, 4c, and 5c). Treating compound 1 with Me(3)NO in acetonitrile solution gives CpW(2)(CO)(6)(mu-PPh(2) )(NCMe) (6). Further treatment of compound 6 with Me(3)NO in acetonitr ile solution affords CpW(2)(CO)(5)(mu-PPh(2))(NCMe)(2) (7). Reaction o f compound 7 and CpW(CO)(3)(PPh(2)) leads to [CpW(CO)(2)(mu-PPh(2))]W- 2(CO)(4) (8). All of the new complexes have been characterized by IR a nd H-1 and P-31 NMR spectroscopies, mass spectrometry, and elemental a nalyses. 6 was also characterized by X-ray crystallography.