Synthesis, spectral and antibacterial studies on bis(cyclopentadienyl) hafnium(IV) derivatives with Schiff bases of benzil-α-monoxime

A series of complexes of the type [(η⁵-C₅H ₅)₂Hf(L)] (L = Schiff base ligand (LH₂), derived by condensing benzil-α-monoxime and aromatic and aliphatic diamines) has been prepared. Tentative structures of the complexes have been proposed on the basis of elemental analysis, electrical conductance, magnetic moment and spectral (IR, electronic and ¹H NMR) data. Proton NMR spectra indicate that there is rapid rotation of the cyclopentadienyl ring around the metal-ring axis on the NMR time scale at 25 °C. Studies were conducted to assess the growth inhibiting potential of the complexes synthesized and the ligands against various bacterial strains.