Cation-Induced dimerization of nickel(II), platinum(II), and palladium(II) meso-tetra(benzo-15-crown-5)porphyrinates
作者:A. Yu. Chernyad’ev、N. M. Logacheva、A. Yu. Tsivadze
DOI:10.1134/s0036023606050068
日期:2006.5
Cation-induced dimerization of nickel(II), platinum(II), and palladium(II) meso-tetra(benzo-15-crown-5)porphyrinates (Ni(II)TCP, Pd(II)TCP, and Pt(II)TCP) on treatment with potassium thiocyanate in a chloroform-methanol solution has been studied by electronic absorption spectroscopy. The formation of [MTCP}(2)(K+)(4)](SCN-)(4) in solution induces a hypsochromic shift of the Soret band and a bathochromic shift of the beta-band with respect to their positions in the spectrum of MTCP. The equilibrium constants (K) for the 2MTCP + 4K(+) = [MTCP}(2)(K+)(4)] processes at 20 degrees C are determined to be as follows: log K (Ni(II)TCP) = 27.31 +/- 1.67, logK(Pd(II)TCP) = 27.16 +/- 1.43, and logK(Pt(II)TCP) = 26.15 +/- 1.56.