Synthesis, spectral and antibacterial studies of bis(cyclopentadienyl)titanium(IV)/zirconium(IV) and mono(cyclopentadienyl)titanium(IV) complexes of antipyrine Schiff bases

The reactions of mono(cyclopentadienyl)titanium(IV) trichloride and bis(cyclopentadienyl)titanium(IV)/zirconium(IV) dichloride with Schiff bases, derived by condensing 4-aminoantipyrine with benzaldehyde (L-1), furfuraldehyde (L-2), pyridine-4-carboxaldehyde (L-3) or salicylaldehyde (L4H), have been studied in anhydrous tetrahydrofuran or dichloromethane and products of types [Cp2M(L)Cl]Cl, [CpTiCl3(L)] (L = L-1, L-2 or L-3); [Cp2M(L-4)]Cl, [CpTiCl2(L-4)], [CpTi(L-4)(2)]Cl [M = Ti-IV or Zr-IV] have been isolated. Tentative structures are proposed for these complexes based upon elemental analyses, electrical conductance and spectral (electronic, IR, H-1 NMR and C-13 NMR) data. Attempts have been made to establish a correlation between antibacterial activity and the structures of the products.