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...
