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Aggregation of meso-tetra-(p-sulphonatophenyl)porphine and its cu(II) and zn(II) complexes in aqueous solution
1Department of Chemistry, McMaster University, Hamilton, Ontario, Canada.
Abstract:
The aggregation of meso-tetra(p-sulphonatophenyl)porphine, an analytical reagent for the determination of metals at low concentration, has been studied over a wide concentration range by both spectrophotometric and (1)H NMR methods. Up to a concentration of about 3 x 10(-4)M, the experimental data were satisfactorily accounted for by a monomer-dimer equilibrium. At higher concentrations, the best fit of the chemical shift data required postulation of a tetramer. Analysis of the experimental data for the Zn(II) complex indicated the occurrence of dimerization at higher concentrations.
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