Carboxy-substituted Phthalocyanine Metal Complexes

Abstract

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...

Synthesis and selected properties of metallo and metal-free 2,3,9,10,16,17,23,24 –octacarboxyphthalocyanines

“…14,27,38,39 According to Opris et al 31 the heating of CuPcOC in the temperature up to 250 C leads to a 13.5% loss of the total mass which indicates the loss of water whereas the decomposition of phthalocyanine molecules starts in the temperature of about 330 C. Also for the series of complexes like CoPcOC, CuPcOC, ZnPcOC, Al(OH)PcOC and Cr(OH)PcOC in the temperatures from 120 C to 150 C the change in mass is caused only by the loss of adsorbed and crystallization water, 30 and if the heating process is continued anhydride fragments are created.…”

“…Metallo and metal-free 2,3,9,10,16,17,23,24-octacarboxyphthalocyanines dissolve well in water with pH above 7, 33 also such complexes as CoPcOC, ZnPcOC, Al(OH)PcOC and Cr(OH)PcOC are water soluble but they do better in alkaline solutions. 30 Moreover metal-free 2,3,9,10,16,17,23,24-octacarboxyphthalocyanine is soluble in DMSO, 34 whereas according to authors solubility in water is limited. The hydroxy aluminium octacarboxyphthalocyanine (Al(OH)PcOC) conjugated with diammine platinum give water-soluble complexes at pH > 8.2.…”

“…43 Also when a concentrated H 2 SO 4 is used the locations of bands with a strong bathochromic shift are obtained because of the protonation of meso-nitrogen atoms. 30 The locations of the bands in UV-Vis absorption spectra for H 2 PcOC, i.a. in aqueous solutions, in solutions with different pH values, in mixed solutions (water-ethanol, watermethanol) and in solutions containing surfactants are presented by Suchan et al 44 In water the location of the Q and B bands changes and the concentration of the studied phthalocyanine has a strong effect on the location.…”

Physical-Chemical Properties of Modified Copper-Phthalocyanine and Its Aqueous Dispersions

“…[13][14][15][16][17][18][19][20][21] При этом достигается модифицирование каждой молекулы MPc необходимым числом функци-ональных фрагментов. Поверхность частиц MPc также может быть модифицирована посредством гетерофазных реакций с органическими молекулами.…”

Thermodynamic characteristics of the dissolution of substituted copper tetraantraquinonoporphyrazines in alkaline aqueous media

“…The presence of bromine in the phthalocya nine molecule leads to an increase in catalytic activity [2,7]. Its solubility in an alkaline water medium makes it easier for hydrophilic functional substituents (e.g., sulfo , hydroxy , and carboxy groups) to exist in the phthalocyanine molecule [2,[8][9][10]. In light of the above, it is understandable that data on the solubility of compounds of the porphyrazine series in different solvents (including alkaline water media) is of great interest.…”