| Abstract
| - The model compounds[η5-1-Ph2P-2,4-Ph2C5H2](CO)3MI(M = Mo, 12; W, 13) have been reacted withstoichiometric amounts of zerovalent palladium. The oxidativeaddition of the M−I moiety on Pd0 took place withformation of complexes[η5-1-Ph2P-2,4-Ph2C5H2](CO)3MPd(PPh3)I(M = Mo, 16; W, 17). Reaction of16 and 17 withBu3SnC⋮C(C6H4)p-NO2(18) led to the formation of the products of transmetalation[η5-1-Ph2P-2,4-Ph2C5H2[(CO)3MPd(PPh3)C⋮O(C6H4)p-NO2(M = Mo, 19; W, 20). Complexes13 and 17 were also characterized by X-raystructure determination.
- To investigate the reaction mechanism of the Pd-catalyzedmetal−carbon bond formation,the model compounds[η5-1-Ph2P-2,4-Ph2C5H2](CO)3MI(M = Mo, 12; M = W, 13) havebeenprepared and their reactions studied under coupling conditions.Treatment of 12 and 13with stoichiometric amounts of zerovalent palladium yields thecomplexes [η5-1-Ph2P-2,4-Ph2C5H2](CO)3MPd(PPh3)I(M = Mo, 16; M = W, 17) by oxidative additionof the M−Imoieties on Pd0. Subsequent reaction of intermediates16 and 17 with 4-nitro-1-[2-(tributylstannyl)ethynyl]benzene(Bu3SnC⋮C(C6H4)p-NO2,18) leads to the formation of thetransmetalation products[η5-1-Ph2P-2,4-Ph2C5H2](CO)3MPd(PPh3)C⋮C(C6H4)p-NO2(M =Mo, 19; W, 20), which have been isolated andcharacterized. Complexes 13 and 17havebeen also characterized by X-ray analysis.
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