Synthesis, structure and spectroscopic properties of nickel(II) macrocyclic and open-chain complexes resulted from 1-phenyl-butane-1,3-dione mono-S-methylisothiosemicarbazone template self-condensation

Self-condensation of 1-phenyl-butane-1,3-dione mono-S-methylisothiosemicarbazone (6) in the presence of nickel(II) acetate in methanol gives rise to a mixture of two complexes: [2,9-bis(methylthio)-5,13-dimethyl-7,14-diphenyl-1,3,4,8,10,11-hexaazacyclotetradeca-2,4,6,9,11,13-hexaenato(2-)N1,N4,N8,N11]nickel(II) (7) and [1-amino-1,6-bis(methylthio)-4,9-dimethyl-11-phenyl-2,3,4,7,8-pentaazaundeca-1,3,6,8,10-pentaenato(-)-11-olato(-)N2,N4,N8,O]nickel(II) (8). Both the macrocyclic complex 7 and the open-chain chelate 8 are characterised by X-ray diffraction methods, which reveal their square-planar structure. Electronic, IR, NMR, electron impact mass spectra and cyclic voltammograms of new compounds are also reported.