Catalytic Activity of Metal Polyphthalocyanines in Autoxidation Reactions

Abstract

The oxidation of cumene and acrolein was carried out using metal polyphthalocyanines as a catalyst. The catalyst activated an oxygen molecule to form a phthalocyanine–O2 complex, which then abstracted the hydrogen atom of a reactant to initiate the oxidation. The catalyst had no effects on the decomposition of cumene hydroperoxide, formed selectively in the oxidation of cumene. The addition of a small amount of pyridine induced a drastic shortening of the induction period as well as a considerable increase in the oxidation rate. The initiation mechanism assumed on the basis of findings on the desorption of oxygen from the catalyst and on the effect of pyridine was confirmed by a kinetic study of the homogeneous liquid-phase oxidation of acrolein.

Phthalocyanines in Macromolecular Phases - Methods of Synthesis and Properties of the Materials

“…1 O 2 + Sub e oxidized Sub (27) It was discussed before that the toxic thiol and sulfide are catalytically oxidized in the presence of Co(II)-phthalocyanines to disulfides and thiosulfate, respectively (Equation (22), (23)). When water soluble phthalocyanines 1 (M = Zn(II), Al(III)OH or Si(IV)(OH) 2 , R = SO 3 H) are employed in the dark no catalytic activity is observed.…”

Novel Network Polymeric Phthalocyanines: Synthesis and Characterization

“…In all cases, the intensities in the UV (soret band transition) and Vis (Q-band transition) were I UV /I Vis 1. This result indicates that all of the polymeric phthalocyanines (3)(4)(5)(6)(7)(8)(9) were structurally uniform polymers.…”

“…[3] Compared to low molecular weight phthalocyanines, relatively few reports describe the synthesis and properties of polymeric phthalocyanines. For the polycyclotetramerization, bifunctional monomers based on tetracarbonitriles for polymers, [4][5][6][7][8][9] various oxy-, arylenedioxy-and alkylenedioxy-bridged diphthalonitriles for polymers [10][11][12][13][14] and other nitriles [15][16][17] or tetracarboxylic acid derivates [18][19][20][21] have been employed, mainly in the presence of metal salts or metals. The polymers exhibit not only very large and accessible surface areas [22] but also good thermal stabilities under inert gas up to $500 8C and under oxidative conditions up to $350 8C.…”

“…[53] The thermal properties of metal-free and metallophthalocyanines were investigated by DSC. DSC curves exhibited exothermic changes for all polymeric phthalocyanines (3)(4)(5)(6)(7)(8)(9) in the region investigated. [54] The curves did not show melting points except for 3 ( Table 4).…”

“…The intensity ratio of l ¼ 236-298 nm and l max (706-883 nm) of the Q-bands in the polymeric phthalocyanines (3)(4)(5)(6)(7)(8)(9) can be seen in Table 2. In all cases, the intensities in the UV (soret band transition) and Vis (Q-band transition) were I UV /I Vis 1.…”