Quadridentate bridging EO42- (E = S, MO, W) ligands and their role as electronic bridges

Three compounds containing two quadruply bonded Mo-2(DAniF)(3) (DAniF = N,N ' -di-p-anisylformamidinate) units linked by tetrahedral EO42- anions (E = S, Mo, W) have been prepared and characterized by crystallography and NMR. The linkers in these [Mo-2(DAniF)(3)](2)(mu -EO4) compounds hold the Mot u nits in an approximately perpendicular orientation and mediate strong elect rochemical communication between them. Each of the three compounds shows tw o quasireversible (mu -SO4) or fully reversible (mu -MoO4, mu -WO4) feature s in its cyclic voltammogram corresponding to successive oxidation of each of its Mot units. The DeltaE(1/2) values are the largest thus far measured for Mo-2-X-Mo-2 bridged complexes and may be sufficiently large to permit i solation of the singly oxidized species.