Comparative reactivity study of cyclopentadienyl and fulvalene molybdenum complexes

The reactions of cis-1,1'-[eta (5):eta (5)-(C5H3CO2Me)(2)]Mo-2(CO)(6) (1), in the presence of 1 equiv. of Me3NO, and [(eta 5-C5H4CO2Me)Mo(CO)(3)](2) ( 2) with dppe produce CO labilization and formation of the dinuclear zwitter ions trans-1,1'-[eta (5):eta (5)(C5H3CO2Me)(2)]Mo-2(CO)(5)(dppe) (3) and di sproportionation species [(eta (5)-C5H4CO2Me)Mo(CO)(2)(dppe)](+) [(eta (5)- C5H4CO2Me)-Mo(CO)(3)](-) (4), respectively. Using the same method, the reac tions of trans-1,1'-[eta (5):eta (5)-(C5H3CO2Me)(2)]Mo-2(CO)(6)I-2 and (eta 5-C5H4CO2Me)Mo(CO)(3)I with PPh3 in the presence of 1 and 2 equiv. of Me3N O yield trans-1,1'-[eta (5):eta (5)-(C5H3CO2Me)(2)]-Mo-2(CO)(4)(PPh3)(2)I-2 (5) and (eta (5)-C5H4CO2Me)Mo(CO)(2)(PPh3)I (6). The reactions of the seve ral anionic carbonyl species {trans-1,1 '-[eta (5):eta (5)-(C5H3CO2Me)(2)]M o-2(CO)(6)}(2-), [(eta (5):eta (5)-C10H8)W-2(CO)(6)](2-) and [(eta (5)-C5H4 CO2Me)Mo(CO)(3)](-) with S2Ph2 give rise to the thiolate-fulvalene complexe s cis-1,1'-[eta (5):eta (5)-(C5H3CO2Me)(2)]Mo-2(CO)(4)(mu -SPh)(2) (7) and (eta (5):eta (5)-C10H8)W-2(CO)(6)(SPh)(2) (8) and the thiolate-bridged dime r [(eta (5)-C5H4CO2Me)Mo(CO)(mu -SPh)](2) (9). Treatment of 6 with 1 equiv. of HC=C-C=H and with (eta (5)-C5H4)Mo(CO)(dppe)(C=C-C=CH), in the presence of Cut at room temperature, afford the cyclopentadiene complexes (eta (5)- C5H4CO2Me)Mo(CO)(2)(PPh3)(C=C-C=CH) (10) and (eta (5)-C5H4CO2Me)(PPh3)(CO)( 2)Mo-(C=C-C=C)-Mo(CO)(dppe)(eta (5)-C5H5) (11), respectively. The reaction of (eta (5)-C5H5)Mo(CO)(dppe)(C=C-C=CH) with Co-2(CO)(8) yields [Co-2{mu -H C2C=C[Mo(CO)(dppe)-(eta (5)-C5H5)]}(CO)(6)] (12). All the new compounds hav e been characterized by analytical and spectroscopic methods. (C) 2001 Else vier Science B.V. All rights reserved.