PREPARATION AND SPECTROSCOPIC PROPERTIES OF 5 7,16-BIS(AZOPHENYL)TETRAAZA[14]ANNULENE NICKEL(II) COMPLEXES

The diazo coupling reaction of a tetraaza[14]annulene nickel(II) compl ex (1) with a series of para-substituted phenyldiazonium tetrafluorobo rates led to the corresponding 7,16-bis(azophenyl) products. The nicke l(II) complexes formed are approximate square-planar coordinations and diamagnetic. The olefinic proton signals at the 7,16-positions of the nickel(II) complexes are destroyed by the diazo coupling reaction in the NMR spectra. The carbon signals at the 7,16-positions exhibit down field shifts of about 30 ppm with the diazo coupling reaction. (C) 199 8 Elsevier Science S.A. All rights reserved.