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

Self-condensation of 1-phenyl-butane-1,3-dione mono-S-methylisothiosemicarb azone (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-tradeca- 2,4,6,9,11, 13-hexaenato(2-)N-1,N-4,N-8,N-11]nickel(II) (7) and [1-amino-1, 6-bis(methylthio)-4,9-dimethy-11-phenyl-2,3,4,7,8-pentaazaundeca-1,3,6,8,10 -pentaenato(-)-11-olato(-)N-2,N-4,N-8,O]nickel(II) (8). Both the macrocycli c complex 7 and the open-chain chelate 8 are characterised by X-ray diffrac tion methods, which reveal their square-planar structure. Electronic, IR, N MR, electron impact mass spectra and cyclic voltammograms of new compounds are also reported. (C) 2001 Elsevier Science B.V. All rights reserved.