Tetrakis(diethyl phosphonate), Tetrakis(ethyl phenylphosphinate)-, and Tetrakis(diphenylphosphine oxide)-Substituted PhthalocyaninesThe title compounds 7, 9, and 11 are obtained by tetramerization of diethyl (3,4-dicyanophenyl)phosphonate (5), ethyl (3,4-dicyanophenyl)phenylphosphinate (8), and 4-(diphenylphosphinyl)benzene-1,2-dicarbonitrile (10). The 31 P-NMR spectra of the phthalocyanines 7, 9, and 11 and of their metal complexes present five to eight signals confirming the formation of four constitutional isomers with the expected C 4h , D 2h , C 2v , and C s symmetry. In the FAB-MS of the Zn, Cu, and Ni complexes of 7 and 9, the peaks of dimeric phthalocyanines are observed. By gel-permeation chromatography, the monomeric complex [Ni (7)] and a dimer [Ni(7)] 2 can be separated. These dimers differ from the known phthalocyanine dimers, i.e., possibly the P(O)(OEt) 2 and P(O)(Ph)(OEt) substituents in 7 and 9 are involved in complexation. The free phosphonic acid complex [Zn (12) (12)], only the peaks of the dimer are present; the ESI-MS confirms the existence of the dimer and the metal-free dimer. In the UV/VIS spectrum of [Zn(12)], the hypsochromic shift characteristic for the known type of dimers from 660 ± 700 nm to 620 ± 640 nm is observed. As in the FAB-MS of [Zn(12)], the free phosphinic acid complex [Zn(13)] shows only the monomer, an ESI-MS cannot be obtained for solubility problems. The UV/VIS spectrum of [Zn(13)] demonstrates the existence of the monomer as well as of the dimer.