Inorganic Chemistry, Vol.41, No.6, 1354-1356, 2002
The first designed syntheses of bis-dimetal molecules in which the bridges are diamidate ligands
The first deliberate syntheses of molecules in which pairs of quadruply bonded Mo-2 units are bridged by N,N'-diarylterephthaloyldiamidate (aryl = Ph, m-CF3Ph) ligands are described. The addition of neutral N,N'-diarylterephthaloyldiamide to 2 equiv of [Mo-2(DAniF)(3)(MeCN)(2)](+) (DAniF = N,N'-di-p-anisylformamidinate) followed by the introduction of excess H3CO- in MeCN results in the formation of (DAniF)(3)Mo-2{(C6H5)NC(O)C6H4(O)CN(C6H5)}Mo-2-(DAniF)(3) (1) and (DAniF)(3)Mo-2{[(m-CF3)C6H5]NC(O)C6H4(O)CN[(m-CF3)C6H5]}Mo-2(DAniF)(3) (2). The DeltaE(1/2) for the oxidation of each Mo-2 unit is greater for these terephthaloyldiamidate-bridged molecules (similar to100 mV) than for the analogous terephthalate-bridged compound (similar to60 mV). Variation in the nature of the substituents on the diamidate nitrogen atoms offers a means to fine-tune the oxidation potentials of the Mo-2 units.