UNEXPECTED PRODUCTS RESULTING FROM REACTIONS OF CP(ASTERISK) IR(ETA(5)-2,5-ME(2)T)(2-DIMETHYLTHIOPHENE) WITH (MU-S)(2)FE-2(CO)(6)(2-) AND (MU-CO)(MU-RS) FE-2(CO)(6)(-)() (ME(2)T=2,5)

The reactions of CpIr(eta(5)-2,5-Me(2)T)(2+) (1) with (mu-S)(2)Fe-2(C O)(6)(2-) and (mu-Co)(mu-n-BuS)Fe-2(CO)(6)(-), which are expected to r esult in either reduction of 1 or nucleophilic attack on the eta(5)-2, 5-dimethylthiophene ring, yield products that contain the reduced CpI r(eta(4)-2,5-Me(2)T) (2) ligand. X-ray diffraction studies of the prod ucts CpIr(eta(4)-2,5-Me(2)T . Fe-2(CO)(5)(mu-S-2)) (6) and Cp*Ir(eta( 4)-2,5-Me(2)T . Fe-2(CO)(5)(mu-S(n)Bu)(2)) (9) show that the CpIr(eta (4)-2,5-Me(2)T) is coordinated through its sulfur atom to an Fe atom o f the Fe-2(mu-S)(2)(CO)(4) dimer core. Reaction of 2 with (mu-S-2)Fe-2 (CO)(6) (4) leads to a completely different product 7 in which the two bridging sulfur atoms of the Fe-2(mu-S)(2)(CO)(4) core are bonded at two carbons of a rearranged 2,5-Me(2)T ligand. Characterization and me chanisms of formation of the new compounds are discussed.