Synthesis, spectral and antibacterial studies of binuclear titanium(IV) / zirconium(IV) complexes of piperazine dithiosemicarbazones

The reactions of mono(cyclopentadienyl)titanium(IV) trichloride and bis(cyclopentadienyl)titanium(IV)/zirconium(IV) dichloride with a new class of dithiosemicarbazone, derived by condensing piperazine dithiosemicarbazide with benzaldehyde (L₁H₂), 2-chlorobenzaldehyde (L ₂H₂), 4-nitrobenzaldehyde (L₃H₂) or salicylaldehyde (L₄H₄) have been studied and different types of binuclear products, viz. [{CpTiCl₂}₂L], [{Cp ₂MCl}₂L], ((L=L₁, L₂ or L ₃), [{CpTiCl}₂L₄] and [{Cp₂M} ₂L₄] (M=Ti or Zr), have been isolated. Tentative structures are proposed for these complexes based upon elemental analyses, electrical conductance, magnetic moment and spectral (electronic, IR, ¹H and ¹³C NMR) data. Attempts have been made to establish a correlation between antibacterial activity and the structures of the products.