Monometallic, homo- and hetero-bimetallic complexes based on redox active tris(3,5-dimethylpyrazolyl)boratomolybdenum and tungsten nitrosyls. Part V.Para-substituent effects on the reduction potentials of arylamide complexes

Abstract

Two series of complexes having the formula [M{HB(3,5-Me2C3N2H)3}(NO)Cl(NHC6H4Z-p)]; in which M=Mo and Z=F, Cl, Br, OMe, SMe, CN, CO2Me or NO2 and M=W and Z=Br, OMe, CN, CO2Me or NO2, have been prepared. The reduction potentials of these new complexes were measured by cyclic voltammetry and, in combination with previously reported data for related species and for [Mo{HB(3,5-Me2C3N2H)3} (NO)I-(NHC6H4Z-p], were used to determine reaction constants for the reduction of [M{HB(3,5-Me2C3N2H)3}(NO)X(NHC6H4Z)]M=Mo and X=I or Cl; M=W, X=Cl.