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Enhancement of the catalytic activity of phthalocyanine catalysts by immobilizing them on polymer matrix has been studied. It has been found that the immobilization of cobalt(II) phthalocyanines on polymers enhances their catalytic activity in the oxidation of sodium diethyldithiocarbamate by air oxygen under mild conditions.

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Cobalt(I1) 2,9,16,23-tetrasulphophthalocyanine and cobalt(I1) of the samples was characterized by electron microscopy and 2,9,16,23-tetra(chlorosulphonyl)phthalocyanine were sup-electron diffraction. The morphology of the matrix strongly ported on TiOz by reaction of the phthalocyanines with depends on the cobalt phthalocyanine derivative. The phthaTi(OR), followed by sol-gel synthesis. The thus obtained so-locyanines in the titania matrices are monomeric or dimeric lid materials are stable in sulfide-containing media and are depending both on the type of substituents of the CoPc derivtherefore suitable as catalysts for HS oxidation. The structure ative and on the titanium alkoxide used as precursors.Phthalocyanines of cobalt and particularly its soluble derivatives are among the most effective catalysts for HS oxidation,['l[21 There were several efforts to support these compounds on various inorpnic supports to combine the advantages of homogeneous and heterogeneous catalysts. For example, C O P C (~-S O~H )~ supported on charcoal is industrially applied because of the technological advantages of heterogeneous catalysts, although the catalytic activity is much lower than in the homogeneous phase. [31[41 Cobalt phthalocyanine (CoPc) derivatives were immobilized by covalent bonding to surface-modified silica gels with high surface coverages. For this purpuse, carboxy-or amino-substituted phthalocyanines were reacted with aminopropyl-or chloropropyl-modified silica. respectively. [51[61 Alternatively, several cobalt phthalocyaninc derivatives were coordinatively bonded to aminopropyl-or imidazolylpropyl-modified silicas via Co -N bonds. Although only one axial position at the cobalt atom is available for the substrate in these supported derivatives, they exhibit high catalytic acitivity in the oxidation of 2-mercaptoethanol, being comparable to or even higher than that of the dissolved tetracarboxy-and tetrasulphophthalocyanines.L71 Substituents influence the catalytic activity: electronwithdrawing substituents enhance and electron-donating substituents decrease the activity of both ~upported [~] [~'[~][~] and homogeneous cobalt phthalocyanines. L8]Another possibility of heterogenization is to polymerize cobalt phthalocyanines. The polymers exhibit a much higher activity in sulfide oxidation than their monomeric couterparts due to the disproportionation of Co(I1) to Co(1) and Co(I1I) followed by energy compensation in the rate determining reaction step, i.e. dioxygen and SH coordination.Sol-gel processing is an alternative route for the heterogenization of homogeneous catalysts. Ll"] Since the catalysts are located inside the gel matrix instead of being anchored to the surface, the stability usually is higher. There is no loss of activity if the porosity of the gel is properly tailored. C O P C (~-S O~H )~ was heterogenized by sol-gel processing starting from Si(OEt),, (EtO)$iMe and (EtO),Si-(CH2)3NH2 as precursors. The aminopropylsilane was used to covalently bond the catalyst to the silicate matrix by reaction o...

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Metal complexes of carboxy-substituted phthalocyanines differing in the number of carboxy groups and their positions and those having carboxy groups together with other substituents were synthesized, and their spectral and some other properties were studied.Among numerous compounds of the phthaocyanine series, carboxy-and sulfo-substituted derivatives attract specific interest due to their good solubility in aqueous media. These derivatives are used in various fields of science and technics, in particular as dyes, catalysts, photosensitizers for photodynamic therapy of cancer, etc. [135]. However, phthalocyanines containing carboxy groups have been studied to a lesser extent than their sulfo-substituted analogs.The present study was aimed at synthesizing carboxy-substituted phthalocyanine metal complexes I3IV differing in the number and position of the carboxy groups, as well as complexes V3VII containing other substituents together with carboxy groups, and studying their properties.Tetra-and octacarboxyphthalocyaninates I3III were synthesized according to Wyler [638] from benzene-1,2,3-tricarboxylic acid, benzene-1,2,4-tricarboxylic acid, and benzene-1,2,3,5-tetracarboxylic acid, respectively, which were prepared in turn by the procedures described in [9]. Octacarboxyphthalocyaninates IV [MPc(4,5-CO 2 H) 8 ] were obtained by reaction of benzene-1,2,4,5-tetracarbonitrile with the corresponding metal salt in boiling DMF in the presence of urea and ammonium molybdate as catalyst.In the synthesis of compounds I3III, compounds A3C are formed initially. The IR spectra of A3C contain absorption bands in the region 15003 1760 cm !1 , which are typical of stretching vibrations of amide carbonyl groups. The synthesis of complexes IV involves intermediate formation of structures D having dicarboximide fragments which give rise to IR absorption at 3100 cm !1 due to stretching vibrations of the imide N3H bonds.Phthalocyaninates A3D were subjected to hydrolysis in aqueous or alcoholic alkali to obtain sodium salts of the corresponding tetra-and octacarboxylic acids, and the latter were converted into the acids by treatment with a mineral acid. I!VII I, R 1 = R 3 = H, R 2 = CO 2 H; M = Co (a), Cu (b), Zn (c), Ni (d), OHAl (e), OHGa (f), OHCr (g). II, R 1 = CO 2 H, R 2 = R 3 = H; M = = Co (a), Cu (b), Zn (c), OHAl (d), OHGa (e), OHCr (f). III, R 1 = R 3 = CO 2 H, R 2 = H; M = Co (a), Cu (b), Zn (c), Ni (d), OHAl (e), OHGa (f), OHCr (g). IV, R 1 = H, R 2 = R 3 = CO 2 H; M = Co (a), Cu (b), Zn (c), AlOH (d), CrOH (e). V, R 1 = H, R 2 = CO 2 H, R 3 = SO 3 H; M = Co (a), Cu (b), Zn (c), FeOH (d). VI, R 1 = H, R 2 = CO 2 H, R 3 = Br; M = Co (a), Cu (b), FeOH (c). VII, R 1 = Br, R 2 = CO 2 H, R 3 = SO 3 H; M = Co.The complexes were purified by reprecipitation from concentrated sulfuric acid, followed by chromatography on silica gel L (403100 mm) using 1-propanol3water325% aqueous ammonia (8 : 10 : 1) as eluent. It is known [3] that template synthesis of substituted phthalocyanines could give mixtures of regioisomers (randomers) whose...