Interactions of cobalt(II) tetrasulfophthalocyanine with nitrite in the presence of nitrate and perchlorate ions

Spectroscopic changes observed on addition of nitrite to solutions of cobal t(II) tetrasulfophthalocyanine ([Co(II)TSPc](4-)) in the presence of NOS or ClO4- are reported. There is spectroscopic evidence for the oxidation of [ Co(II)TSPc](4-) to a [Co(III)TSPc](3-) species in the presence of nitrite i ons. Equilibrium and kinetic studies for the interaction between [Co(II)TSP c](4-) and NO2- are reported. The rate was found to be first order in both [Co(II)TSPc](4-) and NO2-. The rate constant for the forward reaction, k(f) =1.6 x 10(-4) dm(3)mol(-1)s(-1) was determined at 20 degrees C for the inte raction between nitrite ions and [Co(II)TSPc](4-) in the presence of NO3- o r ClO4- ions.