Interactions of cobalt tetrasulfophthalocyanine with alkyl xanthogenates: evidence for hydrophobic effects in the Merox process

Kinetic and binding studies of the thiolate–cobalt tetrasulfophthalocyanine anaerobic reaction as a subset of the Merox process

“…We obtained evidence for hydrophobic effects as well as the pronounced influence of the thiolate basicity on Merox process kinetics, and showed that the variations in values of CoTSPc-thiolate binding constants are due to both of these effects [35,36]. We also demonstrated that the main features of the anaerobic process are qualitatively similar for a wide range of non-aromatic thiolates of varied basicity, including thioacid salts [34][35][36]. (Hereafter, we will not distinguish between the thiolates and thioacid salts calling them just "thiolates" unless otherwise stated.)…”

“…Earlier, using binding and kinetic studies (along with the UV-vis spectrophotometry), we investigated interactions of Co II TSPc with thiolates under anaerobic conditions, as a subset of Reaction 1, in both non-aqueous media [34] and aqueous solutions [35,36]. We obtained evidence for hydrophobic effects as well as the pronounced influence of the thiolate basicity on Merox process kinetics, and showed that the variations in values of CoTSPc-thiolate binding constants are due to both of these effects [35,36].…”

“…(Hereafter, we will not distinguish between the thiolates and thioacid salts calling them just "thiolates" unless otherwise stated.) For instance, all of the thiolates reacting with Co II TSPc in aqueous solutions under anaerobic conditions (Reaction 2) could not completely reduce cobalt, so its oxidation number in the resulting oligomeric thiolate-phthalocyanine complexes is between +1 and +2 [35,36].…”

“…RS − + Co II TSPc K RS − RS − Co II TSPc ↔ RS • Co I TSPc (2) Using thiolates of low basicity as substrates allowed us to reduce the reaction rate [36]. For common basic alkyl thiolates, the bulk of the process takes only seconds for completion, thus making it difficult to obtain full kinetic curves [10].…”

Symmetrical and difunctional substituted cobalt phthalocyanines with benzoic acids fragments: Synthesis and catalytic activity

“…Analysis of obtained results and literature data [25][26][27] suggests that for Co(X)Pc4-6 the mechanism including triple complex formation with followed elimination of RS…”