Role of polycation promoters in the cobalt(II) phthalocyaninetetracarboxylic and ‐octacarboxylic acid‐catalyzed autoxidation of mercaptoethanol

Abstract

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Interactions of cobalt tetrasulfophthalocyanine with thiolate anions in dimethylformamide

“…However, this spin effect in the aqueous medium is not critical because of the spin-spin interactions in the Co II TSPc dimer. This significant facilitation of the thiolate-to-cobalt electron transfer may explain the role of CoTSPc dimerization in reaction (1), which has been emphasized by many authors [8][9][10][11][12][13][14].…”

“…CoTSPc association is suggested to play a critical role in reaction (1) [8][9][10][11][12][13][14]. Thiolate-CoTSPc complexes, except for those of fluorinated aromatic thiolates, also appear to associate in aqueous solutions [15,16].…”

“…The latter process has been used in the synthesis of disulfides and for controlled partial oxidation of thioacid salts to disulfides for metal ore flotation [2][3][4]6]. The kinetics and mechanism of reaction (1) in aqueous media have been studied using basic aliphatic thiols as substrates [1,[7][8][9][10][11][12][13][14]. The first step of the mechanism of reaction (1) is assumed to be the formation of binary thiolate-CoTSPc complexes (Scheme 1) followed by their reaction with oxygen to furnish ternary thiolate-CoTSPc complexes [1,[7][8][9][10][11][12][13][14].…”

Preparation, characterization, and catalytic activity of synthetic carbon-supported (phthalocyaninato)cobalt-containing complexes in dodecane-1-thiol oxidation reaction

“…It is commonly believed that the key difference between physical adsorption and covalent anchoring methods is the formation of a multilayer structure with strong intermolecular interactions in the former case and the formation of the monomeric structure, at least theoretically, in the later case (Scheme 2) [14]. The degree of aggregation, in turn, can control the activity of the respective catalyst but there is no general agreement on the relationship between the aggregation state of substituted cobalt phthalocyanines and their catalytic activity [18][19][20][21].…”