Yeni ftalosiyanin sentezleri ve özelliklerinin incelenmesi

Abstract

Bu çalışmada, simetrik yapıda sekiz adet taç eter grubunun oksi metil ve azametil grupları ile bağlandığı, çözünebilir özellikte yeni metal ftalosiyaninlerin sentezi amaçlanmıştır. İlk olarak, l,2-bis{[(benzo-15-crown~5)-4*-il]oksimetil}-4,5- dibromo benzen (l)'in, CuCN ile yüksek sıcaklıkdaki reaksiyonundan { 2, 3, 9, 10, 16, 17, 23, 24-oktakis [ [ ( benzo-15-crown-5 ) -4 ' -il] oksimetil] Ftalosiyaninato} bakır (II) (5) sentezi gerçekleştirilmiştir Uygun metal tuzlarının, l,2-bis{ [(benzo-15-crown-5)-4'-il]- oksimetil}-4,5-disiyanobenzen (2) ile yüksek sıcaklıkdaki reaksiyonla rından, Nİ(II), Co(II), Pb(II) ftalosiyaninler (sırasıyla 6, 7, 8) elde edilmiştir. Son olarak, l,2-bis{ [[(benzo-15-crovm-5)-4'-il]p_.tolilsülfonil] azametil} -4, 5-dibromobenzen(£) 'in CuCN ile yüksek sıcaklıkdaki reaksi yonundan, {2, 3, 9, 10, 16, 17., 23, 24-oktakis [ ['[( benzo-15-crown-5 ) -4 ' -il] - p.tolilsülfonil] azametil] ftalosiyaninato) bakır ( II) (9) ele geçmiştir. Sentezi yapılan ara ye son ürünlerin yapıları., elementel analiz, l.R., U.V-Görünür Bölge, H-NMR yöntemleriyle belirlenmiştir. (5)' in alkali metal bağlayabilme özellikleri araştırılmış, yapı daki taç eter gruplarının alkali metaller ile molekül içi sandviç kompleksleri oluşturduğu,, söz konusu metaller mevcudiyetinde alman U.V. -Görünür bölge spektrumları incelenmesinden anlaşılmıştır.

Metal free and metal containing phthalocyanines have been investigated extensively for their chemical, photochemical, and thermal properties. Phthalocyanines substituted with -crown ether groups have been shown to form discotic mesophases and ion channels for alkali metal cations." At the same time, these compounds have become soluble in common organic solvents as a result of this substitutions. The alkyl substitution increases the solubility of phthalocyanines and the effect of bulkyl substituents is shown to be higher than that of the smaller ones, e.g. methyl. -Substitution of a phthalocyanine with eight crown-ether groups, therefore, is expected to enhance the solubility and improve the intermolecular stacking. In the present work we have synthesized for the first time phthalocyanines containing eight benzo[l5-crown-5] substituents bridged -with oxymethyl and azamethyl groups namely {2,3,9,10,16,17,23, 24-octakis [ [( benzo-15-crown-5 ) -4 ' -yl] -oxymethyl] phthalocyaninato ) metals (II) (5-8) and {2,3,9,10,16,17,23,24-octakis[[[(benzo-15-crown-5) 4'-yl]p.tolylsulphonyl] azamethyl] phthalocyaninato) copper (II) (9) 1, 2-Bis { [ ( benzo-15-crown-5 ) -4 ' -y l] oxymethyl) -4, 5-dibromo benzene (1) was obtained by the condensation of 4'-hydroxybenzo[l5-crown-5] with l,2-dibromo-4,5-bis(bromomethyl)benzene. In the "H-NMR spectra of (1), two aromatic protons (CHg^Qjna-tic) are observed at 7.76 ppm; six aromatic proton (crown ether CHaroma--Cxc ) a-t 6.82-6.38 ppm; four aromatic methylene protons (Ar-O-C)at 4.98 ppm; thirty two aliphatic etheric protons (crown ether CMgaiiphatic) at 4.11-3.71 ppm. In the I.R. spectrum, characteristic absorption bands of the (1), (.GHaroma^^c are observed at 3070 cm"1; (CHali phatic ) 2920-2870 cm-1; (Ar-0-Cj 1260-1220 cm", (C-0-G) 1180-1125 cm"1; C-Br 620 cm-1. (1) was treated with CuCN in refluxing quinoline under argon for 4h to yield {2,3,9,10,16,17,23,24-octakis[[(benzo-15-crown-5)- 4 !-yl]oxymethyl]phthalocyaninato} copper (II) (5). The reaction of (1) with CuCN in pyridine in a sealed glass tube at 200° C gave same product (5). Pure copper phthalocyanine was isolated by column chromatography on Al 0 with (50:1) chloroform: methyl alcohol as the eluent. In the I.R. spectrum, characteristic absorption bands of ( CH ^. ^r>on low __, J- (5) are observed at 3070 cm (CH ); 1640 cm' 118BÜÎ25 cm -1 (C-0-C); "1,"\ aromatic» 1 (fcNTjl ); 2920-2870 cm 1260-1220 cm" (Ar-0-C); 750 cm ~ (C-H). The visible portion of the^spectrum of (5) was solvent-dependent; while the single intense TWr transition (Q band) was observed at 690 nm and a shoulder at 650 nm in chloroform, they were shifted to 685 nm and 632 in pyridine. The change in the spectra can be attributed to monomeric and oligomeric phthalocyanine species, the latter being more favorable in polar solvents. (2) can be considered as an intermediate step in the synthesis of (5) from (1). Therefore, it can be. isolated from the same reaction mixture by employing suitable conditions for this purpose. (1) was treated with CuCN in TMU under completely anhydrous conditions and N2 atmosphere. The pure product was isolated by column chromatography on Al20g. In the l-H-NMR spectra of (2) > two Figure. 1. {2,3,9,10,16,17,23,24-octakis[[(benzo-15-crown-5)-41-yl]- oxymethyl] phthalocyaninato} copper ( II ) ( 5 ) xi aromatic protons (CHaromatic) are observed as singlet at 8.04 ppm, six aromatic protons (crown ether CHaromatic) &s multiplet at 6.84- 6.37 ppm; for methylenic protons (Ar-CH2) as singlet at 5.10 ppm; and thirty two aliphatic etheric protons (crown ether CH2aiipnatic ) as multiplet at 4.10-3.58 ppm. In the I.R. spectrum of (2)., the only new absorption other than those for (1) is CsN stretching band at 1 ~ 2220 cm-1 A mixture of (2)., NiCl2.6H20, quinoline was heated. and stirred at 170° C for 6h under nitrogen. Nickel phthalocyanine(Gpwas isolated by column chromatography.ûn AI2O3. In the !H-NMR spectra of (6 ) ; eight aromatic protons (CHaromatic) appear as singlet at 8.02 ppm; twenty four aromatic protons (crown ether CH^Q^-tic ) aPPear ss multiplet at 6.78-6.35.ppm; sixteen aromatic methylenic protons (Ar-CH2) appear as singlet at 5.07 ppm; and one hundred and twenty eight aliphatic etheric protons (crown ether CH2aliphatic^ aPPear as multiplet at 4.11-3.68 ppm. In the I.R. spectrum, characteristic absorbtion bands of the (6) is similar with (5).. In the U.V.-visible (chloroform) of (6) : A^, (log e )= 239(4.89); 285(4.73); 332(4.27); 640(4.15); 670(4.34). A mixture of (2), CoCl2.6.H2o, ethyleneglycol was heated and stirred at 180° C for 8h under nitrogen. Cobalt phthalocyanine (7) isolated by column chromatography on Al203- In the I.R. spectrum characteristic absorption bands of (7) is similar with (5). U.V.-visible (chloroform) of (7) : Xmax, (log ?) = 250(4.88); 300(4.97); 335(4.88); 640(4.72); 685(4.88). The reaction of (2) with PbO in ethyleneglycol in a sealed glass tube at 190°C, gave the lead phthalocyanine (8). In the I.R. spectrum, characteristic absorption bands of (8) is similar with other metallo phthalocyanines. U.V.-visible spectrum of (8) (chloroform) : ^max(loge): 282(4.97); 339(4.93); 620(4.73); 678(5.08). The first step for the synthesis of azamethyl bridged crown ether phthalocyanine was the synthesis of 4' -amino benzo[l5-crown-5] which was tosylated with p_.toluenesulphonyl chloride in pyridine at 5-10° C to obtain 4'-p_.tolylsulphonylaminobenzo[l5-crown-5j (3). In the %-NMR spectra of (3); one aza proton (-NH-Tos.) is observed as singlet at 9.8 ppm; four (Tos. 0^0,^.^) proton as two doublet at 7.60-7.30 ppm, three aromatic proton (crown ether CH^Q^-fc^ ) as two doublet and one multiplet at 6.79-6.56 ppm, sixteen aromatic methylenic protons (crown ether cH2ali_h t- ) as multiplet at 3.96-3.33 ppm, Xll three protons (T06.CH3J as singlet at 2.32 ppm. In the I.R. spectrum of (3); shows peaks at 3050 cm-1 (CHaromatics) > 2835, 2905, 2920 cnr1 (CHaliphatics')» 1335, 1175, 1160 cm-1 (R-SO2-NHR), 1285, 1230 cm-1 (Ar-0-C), 1135 cm"1 (C-0-C),. 850 cm"1 (N-H)rocking, 3140 cm-1 (N-H) stretching. 1,2^818 { [(benzo-15-crown-5)-4'-yl]p_.tolylsulphonyl} azamethyl 4,5-dibromobenzene (4) obtained by the reaction of (3) with 1,2- dibromo-4,5-bis(bromomethyl) benzene,, in dry DMF for 48h at 35-40°C. In the.I.R. spectrum of (4); shows peaks at 3050 cm-1 ( CH^omatic ) ", 2910, 2850 cm-1 (CHaiipnatic) î 1340 cm_1 (:Ar~N 'j > 1160' 1180 cm~1 (R-S02-NHR)., at 1260, 1230 cm-1 (Ar-0-C); at 1130 cm-1 (C-0-C). In the H-NMR of (4) ; two aromatic protons (CHaromatic^ are observed as singlet at 7.28 ppm, eight proton (Tos-CHaromatic^ aB two doublet at 7.56-7.32 ppm, six aromatic proton as dublet and multiplet at 6.66-6.37 ppm, four aromatic methylenic proton as singlet at 4.71 ppm, thirty two alifatic ether i c protons asrmultiplet at 4.08-3.72 ppm, three protons (Tos.CHg) as singlet at 2.44 ppm. (4) (4) was treated with CuCN in ref luxing TMÜ in a sealed glass tube Figure 2. {2,3,9,10,16,17,23,24-octakis[[[(benzo-15-erown-5)-4,-yl]- £.tolylsulphonyl] azamethyl] phthalocyaninato) copper (II) (9) XI 11 to obtain (2, 3, 9, 10, 16, 17, 23, 24-octakis [ [ [ ( benzo-15-crown-5-4 ' -yl'J £. tolylsulf onyl] azamethyl] phthalocyaninato} copper ( II ) ( 9 ). Reaction mixture was heated and stirred at 180° C for 8h. Crude (-9) was purified by column :chromatograply on alumina. In the I.R. spectrum of 49); the only new absorption other than those for (4) is (C=N) band 1640 cm"1. U.V. -visible spectrum of (9)- (chloroform): Xmax(loge) 240(5.32); 342(4.97); 616(4.67); 655(4.63); 684(5.44). In order to see the effect of alkali cations, on the aggregation behavior of the phthalocyanine crowns by visible spectra, (5) was dissolved in dichloromethane, and the metal salt (NaSCN, KSCN), dissolved in ethanol, was added. In contrast to the blue shifts obtained with the tetrakis ( crown ether) substiimted phthalocyanines, there was no observable change in the^spectra due to the various metal ions. Especially with K, which prefers formation of sandwich type complexes with benzo-15-crown-5 units, these results can be regarded as the indication for an intramolecular complexation of. crown ether units rather than for intermolecular ph-thalocyanine dimers. The alkali ion binding ability of (5), having eight crown ether units, was estimated by solvent extraction of alkali metal picrates from water to chloroform. Examination of the data revealed the highest affinity to potassium among the other cations in order K > Na > Rb > Cs > Li.