Monometallic, homo- and hetero-bimetallic complexes based on redox-active tris(3,5-dimethylpyrazolyl)borato molybdenum and tungsten nitrosyls. Part 7. Compounds containing strongly interacting redox centres derived from para-substituted anilines and phenols

Abstract

The compounds [ML(NO)X(NHC₆H₄ZH)][L = tris(3,5-dimethylpyrazolyl)borate; Z = NH; M = Mo, X = I; M = W, X = Cl; Z = O; M = Mo, X = I; M = W, X = Cl; Z = S, M = Mo, X = Cl], [{ML(NO)X}₂(NHC₆H₄NH)](M = Mo, X = Cl or I; M = X = Cl), [{ML(NO)X}₂(NHC₆H₄O)](M = Mo, X = Cl or I; M = W, X = Cl), [{MoL(NO)Cl}₂(OC₆H₄O)], and [MoL(NO)I(YC₆H₄Z)WL(NO)Cl](Y = Z = NH; Y = O, Z = NH; Y = NH, Z = O) have been prepared. Cyclic voltammetric and coulometric studies established that the monometallic species undergo a one-electron reduction, whereas the bimetallic species are reduced in two one-electron steps. The electrochemical data suggest that the redox centres in the bimetallic complexes influence each other strongly.