SYNTHESIS, STRUCTURE AND SUBSTITUTION-REACTIONS OF A HETERODIMETALLICTUNGSTEN-MANGANESE COMPLEX [(ETA(5)-C5H5)(OC)(2)W(MU-H)(MU-PPH(2))MN(CO)(4)]

The room temperature reaction of [(eta(5)-C5H5)W(CO)(3)(PPh(2))] with [Mn(CO)(5)](-) in tetrahydrofuran (THF) followed by protonation with H 3PO4 gives [(eta(5)-C5H5)(OC)(2)W(mu-H)(mu-PPh(2))Mn(CO)(4)] 1 as the major product. Among the identified minor products from this reaction are [Mn-2(CO)(9)(PPh(2)H)] 2a, [Mn-2(CO)(9)(PPh(2)PPh(2))] 2b, [Mn-2(m u-H)(mu-PPh(2))(CO)(8)] 2c, and [Mn-2(mu-PPh(2))(2)(CO)(8)] 2d. (CO)-C -13 reacts with complex 1 substituting both the manganese and tungsten carbonyl groups. In contrast, other two-electron donor ligands, L, on ly substitute the manganese carbonyl groups to give the substituted pr oducts ta(5)-C5H5)(OC)(2)W(mu-H)(mu-PPh(2))Mn(CO)(2)L(2)] (L = P(OMe)( 3) 3a, PMe(2)Ph 3b, PMePh(2) 3c, PPh(2)H 3d), ta(5)-C5H5)(OC)(2)W(mu-H )(mu-PPh(2))Mn(CO)(2)L(2)] (L = P(OMe)(3) 4a or PMe(2)Ph 4b). In the c ase of the photolytic reaction of 1 with the diphosphine, dppm (dppm = Ph(2)PCH(2)PPh(2)), two products are obtained, one in which the ligan d is chelated to the manganese centre, (5)-C5H5)(OC)(2)W(mu-H)(mu-PPh( 2))Mn(CO)(2)(dppm)] 5, and the other in which the ligand bridges the t ungsten manganese centres, -C5H5)(OC)(2)W(mu-H)(mu-PPh(2))(mu-dppm)Mn( CO)(3)] 6. Conversion of complex 5 to 6 can be achieved by prolonged U V irradiation of 5. A single crystal X-ray diffraction study for [(eta (5)-C5H5)(OC)(2)W(mu-H)(mu-PPh(2))Mn(CO)(4)] 1 is presented.