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Microwave-assisted synthesis and characterization of new soluble metal-free and metallophthalocyanines substituted with four tetrathiamacrocycles through oxy bridges
Inorganic Chemistry Communications 11 (2008) 630–632
Contents lists available at ScienceDirect
Inorganic Chemistry Communications journal homepage: www.elsevier.com/locate/inoche
Microwave-assisted synthesis and characterization of new soluble metal-free and metallophthalocyanines substituted with four tetrathiamacrocycles through oxy bridges _ Zekeriya Bıyıklıog˘lu, Irfan Acar, Halit Kantekin * Department of Chemistry, Faculty of Arts and Sciences, Karadeniz Technical University, 61080 Trabzon, Turkey
a r t i c l e
i n f o
Article history: Received 15 January 2008 Accepted 22 February 2008 Available online 4 March 2008
Keywords: Tetrathiamacrocycles Metallophthalocyanine Synthesis Microwave Phthalonitrile
a b s t r a c t The new soluble metal-free and Ni(II), Zn(II), Co(II), Cu(II), Pb(II) phthalocyanines with four, tetrathiamacrocycles were obtained from 4-[(11-hyroxy-1,5,9,13-tetrathiacyclohexadecan-3-yl)oxy]phthalonitrile 3 and the corresponding divalent metal salt (NiCl2, Zn(CH3COO)2, CoCl2, CuCl2 and PbO). Metal-free and metallophthalocyanines showed the enhanced solubility in organic solvents. The structures of the target compounds were confirmed using elemental analysis, IR, 1H NMR, 13C NMR, UV–vis and MS spectral data. Ó 2008 Elsevier B.V. All rights reserved.
Metal-free and metallophthalocyanines have enjoyed considerable industrial importance for use in dyestuffs, paints, colors for metal surfaces, fabrics and plastics. Meanwhile, chemical and physical studies of metal Pcs and their derivatives are also pursued by worldwide chemists for their potential applications in many areas. The functions of metal-free and metal Pcs and their derivatives are almost based on a redox or electron transfer reaction [1–3]. Applications of phthalocyanines are limited due to their insolubility in common organic solvents and water [4,5]. Phthalocyanines possess an extended p-conjugated electron system which permits p-stacking between planar macrocycles provided the distance between the macrocycles is sufficiently small [4]. Adding substituents to the periphery of the macrocycles increases their solubility since these substituents increase the distance between the stacked phthalocyanines and enable their solvation [6,7]. Phthalocyanine complexes are capable of binding alkali metal ions and provide donor sites for binding transition metal ions, leading to homo- and heteronuclear complexes. As donors, thioether moieties can be placed between oxa and aza groups for their tendency to complex with alkali and transition metal ions [8,9]. However, phthalocyanines with N- and O-donor substituents are frequently encountered, those with thioether moieties are rather rare [10,11]. A literature survey [12–16] shows that most * Corresponding author. Tel.: +90 462 377 2589; fax: +90 462 325 3196. E-mail address: [email protected] (H. Kantekin). 1387-7003/$ - see front matter Ó 2008 Elsevier B.V. All rights reserved. doi:10.1016/j.inoche.2008.02.030
of the recent work on thioether-substituted phthalocyanines has been patented for applications as IR absorbers [17]. We have previously synthesized phthalocyanines by microwave irradiation [18–23]. The present paper describes the preparation of new soluble metal-free and metallophthalocyanines carrying four 16-membered tetrathiamacrocycles with oxy bridges. The synthetic routes to 3–9 are summarized in Scheme 1. The original precursor compound 3 [24] for the synthesis of phthalocyanines was obtained by nitro displacement reaction of compounds 1 [25] and 2 [26] using K2CO3 as a catalyst in DMF by stirring at room temperature. Cyclotetramerization of macrocyclic dicyano derivative 3 with anhydrous metal salts (NiCl2, Zn(CH3COO)2, CoCl2, CuCl2 and PbO) and 2-(dimethylamino)ethanol at 175 °C, 350 W in microwave oven led to the formation of metal-free and metallophthalocyanines. In the IR spectrum of 3, stretching vibrations of O–H, aromatic and aliphatic CH, nitrile (C„N) groups were observed at 3435, 3071, 2923–2846 and 2230 cm 1, respectively. In addition, comparison of the IR spectrum of compound 3 and 4-nitrophthalonitrile 2 gave support for the proposed structure. These indicated the formation of 3 by the disappearance of the NO2 band of 4-nitrophthalonitrile at 1538 cm 1 and the appearance of new absorptions at 1092–1020 cm 1 belonging to ether group. 1H NMR spectrum of 3 showed new signals at d = 7.76 (d, 1H, Ar-H), 7.34 (s, 1H, Ar-H), 7.24 (d, 1H, Ar–H) belonging to aromatic protons. The 13C NMR spectrum of 3 indicated the presence of nitrile carbon atoms in 3 at d = 115.51 and 115.14 ppm. The MS spectrum of compound 3
Z. Bı yı klı og˘lu et al. / Inorganic Chemistry Communications 11 (2008) 630–632
631
CN S
S
S
S
HO
CN OH O2N
CN
dry DMF dry K2CO3
S
S
S
S
HO
O
CN
2
3
1
DMAE MW
OH
HO S
S S
S
S
S S
S O
O
N N
N N
N
M N
N N
O
O
S
S S
S
S
S S
S
OH
HO
Compound M
4
5
6
7
8
9
2H Ni Zn Co Cu Pb
Scheme 1. The synthesis of the metal-free phthalocyanine and metallophthalocyanines.
bands, one of them in the visible region at about 614–728 nm corresponding to the Q band, and the other in the UV, approximately at 300 nm. The split Q bands in 4, which are characteristic for metal-free phthalocyanines were observed at kmax = 710, 674, 647 and 614 nm. These Q band absorptions show the monomeric species with D2h symmetry and due to the phthalocyanine ring related to the fully conjugated 18 p-electron system [34–36]. The presence of strong absorption bands in 4 in the near UV region at kmax = 345 and 295 nm also shows Soret region B bands which have been ascribed to the deeper p–p* levels of LUMO transitions (see Fig. 1).
2
10-5 ε / dm3 mol-1cm-1
displayed the [M + Na]+ parent ion peak at m/z = 477, which confirms the same structure. The IR spectra of metal-free 4 [27] and metallophthalocyanines 5–9 [28–32] are very similar. A diagnostic feature of the formation of compound 4 from dinitrile 3 is the disappearance of the sharp C„N vibration at 2230 cm 1. The stretching vibrations at 3285 cm 1 for compound 4 can be attributed to the N–H band of the inner core of the metal-free phthalocyanine. The 1H NMR spectrum of compound 4 indicates the aromatic protons at d 8.01, 7.82, 7.45, broad O–H proton at d 5.12 and the aliphatic ether protons at d 4.88–1.81 ppm. The inner core protons (N–H) of this compound 4 could not be observed because of the probable strong aggregation of the molecule [33,20]. The mass spectrum of this compound 4 at m/z = 1820 [M]+ lends support to the proposed formula for this structure. In the IR spectra of metallophthalocyanines 5–9, cyclotetramerization of dinitriles 3 to Pcs 5–9 was confirmed by the disappearance of the sharp –C„N vibration at 2230 cm 1. The 1H NMR spectra of metal-free 4, nickel(II) 5, zinc(II) 6, cobalt(II) 7 and lead(II) 9 phthalocyanines are almost identical. 1H NMR measurement of the copper(II) phthalocyanine 8 was precluded owing to its paramagnetic nature. In the mass spectrum of Ni(II), Zn(II), Co(II), Cu(II) and Pb(II) phthalocyanines, the presence of molecular ion peaks at m/z = 1878 [M + 1]+, 1884 [M]+, 1880 [M + 2]+, 1882 [M]+ and 2025 [M]+, respectively, confirmed the proposed structures. Elemental analysis data were satisfactory. Metal-free phthalocyanine 4 and metallophthalocyanines 5–9 showed typical UV-visible spectra with two significant absorption
1.5
1
0.5
0 200
300
400
500
600
700
800
900
λ ( nm ) Fig. 1. UV–vis spectra of compounds 4 (–), 5 (—) and 6 (. . .) in chloroform.
632
Z. Bı yı klı og˘lu et al. / Inorganic Chemistry Communications 11 (2008) 630–632
Metallophthalocyanines 5–9 showed the expected absorptions at the main peaks of the Q- and B-bands appearing at kmax = 683, 689, 683, 689, 728 nm and 300, 311, 302, 295, 299 nm, respectively. This result is typical of metal complexes of substituted and unsubstituted Pcs with D4h symmetry [37]. Usually, peripheral tetra-substituted phthalocyanines are a mixture of four constitutional isomers (with C4h, D2h, C2v and Cs symmetry).
[28]
Acknowledgement This study was supported by the Research Fund of Karadeniz Technical University, project no: 2006.111.002.1 (Trabzon-Turkey). References [29] [1] A. Gouloumis, T. Torres, Org. Lett. 1 (1999) 1807. [2] P. Ka-Wo, Y. Yan, L. Xi-You, KPNg. Dennis, Organometallics 18 (1999) 3528. [3] T. Fukuda, EA. Makarova, EA. Lukyanets, N. Kobayashi, Chem-A Eur. J. 10 (2004) 117. [4] M. Hanack, M. Lang, Adv. Mater. 6 (1994) 819. [5] W. Eberhardt, M. Hanack, Synthesis 1 (1997) 95. [6] Ö. Bekarog˘lu, J. Porp. Phthalocyan. 4 (2000) 465. [7] P. Haisch, M. Hanack, Synthesis 10 (1995) 1251. [8] S.G. Murray, F.R. Hartley, Chem. Rev. 81 (1981) 365. [9] S. Dabak, A.G. Gürek, E. Musluog˘lu, V. Ahsen, New J. Chem. 25 (2001) 1583. [10] W.A. Snow, J.R. Griffith, Macromolecules 17 (1984) 1614. [11] D. Wöhrle, G. Schnurpfeil, G. Knothe, Dyes Pigments 18 (1992) 91. [12] I. Cho, Y. Lim, Mol. Cryst. Liq. Cryst. 154 (1988) 9. [13] A. Lux, GG. Rozenberg, K. Petritsch, S.C. Moratti, A.B. Holmes, R.H. Friend, Synth. Met. 102 (1999) 1527. [14] H. Eichorn, D. Wöhrle, D. Pressner, Liq. Cryst. 22 (1997) 643. [15] K. Ban, K. Nishizawa, K. Ohta, H. Shirari, J. Mater. Chem. 10 (2000) 1083. [16] AG. Gürek, V. Ahsen, D. Luneau, J. Pecaut, Inorg. Chem. 40 (2001) 4793. [17] PJ. Duggan, PF. Gordon, Eur. Pat. 1 (1985) 55780. [18] Z. Bıyıklıog˘lu, H. Kantekin, M. Özil, J. Organomet. Chem. 692 (2007) 2436. [19] Z. Bıyıklıog˘lu, H. Kantekin, Transit. Met. Chem. 32 (2007) 851. [20] H. Kantekin, Z. Bıyıklıog˘lu, Dyes Pigments 77 (2008) 98. [21] H. Kantekin, Z. Bıyıklıog˘lu, Dyes Pigments 77 (2008) 432. [22] Z. Bıyıklıog˘lu, H. Kantekin, J. Organomet. Chem. 693 (2008) 505. [23] H. Kantekin, G. Dilber, Z. Bıyıklıog˘lu, J. Organomet. Chem. 693 (2008) 1038. [24] Synthesis of 4-[(11-hydroxy-1,5,9,13-tetrathiacyclohexadecan-3-yl)oxy] phthalonitrile 3: 1,5,9,13-tetrathiacyclohexadecane-3,11-diol 1 (2 g, 6.0 mmol) was dissolved in anhydrous DMF (40 ml) under N2 atmosphere and 4-nitrophthalonitrile 2 (1.03 g, 6.0 mmol) was added to the solution. After stirring for 15 min, at room temperature, dry fine-powdered potassium carbonate (3.31 g, 24.0 mmol) was added portionwise within 2 h with efficient stirring. The reaction mixture was stirred under N2 at room temperature for 4 days. The reddish-brown mixture was extracted with chloroform (25 ml). The organic layer was separated, washed with water and then dried over Na2SO4. After evaporation of the solvent the product was crystallized from ethanol as pale yellow crystals. Yield: 2.04 g (74%), mp: 92 °C. Anal. Calc. for C20H26N2O2S4: C, 52.83; H, 5.76; N, 6.16; S, 28.21%. Found: C, 52.80; H, 5.97; N, 6.09; S, 28.46. IR (KBr tablet), mmax/cm 1: 3435 (O–H), 3071 (Ar–H), 2923–2846 (Aliph. C–H), 2230 (C–N), 1592, 1558, 1497, 1413, 1317, 1256, 1168, 1092, 1020, 989, 852, 525. 1H NMR. (CDCl3), (d:ppm): 7.76 (d, 1H, Ar–H), 7.34 (s, 1H, Ar–H), 7.24 (d, 1H, Ar–H), 4.66 (m, 1H, CH–O), 3.90 (m, 1H, CH–OH), 3.04–2.62 (m, 16H, CH2–S), 1.96 (m, 4H, CH2), 1.62 (br, 1H, O–H). 13C NMR. (CDCl3), (d:ppm): 160.75, 135.46, 120.73, 120.27, 117.68, 115.51, 115.14, 107.96, 78.75, 78.67, 40.58, 38.12, 34.71, 31.68, 29.36. MS (ES+), (m/z): 477 [M + Na]+. [25] V.B. Pett, G.H. Leggett, T.H. Cooper, P.R. Reed, D. Situmeang, L.A. Ochrymowycz, D.B. Rorabacher, Inorg. Chem. 27 (1988) 2164. [26] G.J. Young, W. Onyebuagu, J. Org. Chem. 55 (1990) 2155. [27] Synthesis of metal-free phthalocyanine 4: 4-[(11-hydroxy-1,5,9,13tetrathiacyclohexadecan-3-yl)oxy]phthalonitrile 3 (0.35 g, 0.76 mmol) was ground together in a microwave oven and 2-(dimethylamino)ethanol (3.0 ml) was added. The reaction mixture was irradiated in microwave reaction oven at 175 °C, 350 W for 8 min. After being cooled, the reaction mixture was poured into 25 ml of ethanol and the dark green precipitate that formed was separated by filtration. The crude metal-free phthalocyanine mixture was washed with ethanol, water, diethyl ether and then dried in vacuum. The solid product was purified by preparative thin layer chromatography (TLC) using chloroform solvent system. This compound is soluble in CHCl3, CH2Cl2, CH3COCH3 (acetone), THF, DMF, DMSO. Yield: 189 mg (55%), mp > 198– 200 °C. Anal. Calc. for C80H106N8O8S16: C, 52.77; H, 5.87; N, 6.15; S, 28.18%. Found: C, 52.85; H, 6.0; N, 6.40; S, 28.29. IR (KBr tablet) mmax/cm 1: 3400 (O– H), 3285 (N–H), 3060 (Ar–H), 2910–2846 (Aliph. C–H), 1606, 1475, 1417, 1316, 1230, 1094, 1013, 821, 744. 1H NMR. (CDCl3), (d:ppm): 8.01 (d, 4H, Ar–H), 7.82
[30]
[31]
[32]
[33] [34] [35] [36] [37]
(s, 4H, Ar–H), 7.45 (d, 4H, Ar–H), 5.12 (br, 4H, O–H), 4.88 (m, 4H, CH–O), 3.70 (m, 4H, CH–OH), 3.36–2.61 (m, 64H, CH2-S), 1.81 (m, 16H, CH2). UV–vis (chloroform): kmax/nm: [(10 5 e dm3 mol 1 cm 1)]: 295 (5.11), 345 (5.08), 614 (4.66), 647 (4.83), 674 (5.22), 710 (5.29). MS (ES+), (m/z): 1820 [M]+. Synthesis of nickel(II) phthalocyanine 5: The same procedure as above was adopted by using compound 3 (0.35 g, 0.76 mmol), anhydrous NiCl2 (25 mg 0.19 mmol) and 2-(dimethylamino)ethanol (2.5 ml). The solid product was purified by preparative thin layer chromatography (TLC) using chloroform/ methanol (9:1) solvent system. This compound is soluble in CHCl3, CH2Cl2, CH3COCH3 (acetone), THF, DMF, DMSO. Yield: 231 mg (64%), mp > 255– 257 °C. Anal. Calc. for C80H104N8NiO8S16: C, 51.18; H, 5.58; N, 5.97; S, 27.33%. Found: C, 51.00; H, 5.86; N, 5.80; S, 27.40. IR (KBr tablet) mmax/cm 1: 3417 (O–H), 3060 (Ar–H), 2912–2835 (Aliph. C–H), 1606, 1475, 1412, 1227, 1119, 1089, 1061, 952, 834. 1HNMR. (CDCl3), (d:ppm): 8.08 (d, 4H, Ar–H), 7.90 (s, 4H, Ar–H), 7.54 (d, 4H, Ar–H), 5.24 (br, 4H, O–H), 4.96 (m, 4H, CH–O), 3.78 (m, 4H, CH–OH), 3.37–2.65 (m, 64H, CH2–S), 1.88 (m, 16H, CH2). UV–vis (chloroform): kmax/nm: [(10–5 e dm3 mol–1 cm–1)]: 300 (5.07), 350 (5.05), 614 (4.67), 683 (5.15). MS (ES+), (m/z): 1878 [M + 1]. Synthesis of zinc(II) phthalocyanine 6: The same procedure as above was adopted by using compound 3 (0.35 g, 0.76 mmol), anhydrous Zn(CH3COO)2 (35 mg, 0.19 mmol) and 2-(dimethylamino)ethanol (2.5 ml). The solid product was purified by preparative thin layer chromatography (TLC) using chloroform/petroleum ether/methanol (8:1:1) solvent system. This compound is soluble in CHCl3, CH2Cl2, CH3COCH3 (acetone), THF, DMF, DMSO. Yield: 215 mg (60%), mp > 230–232 °C. Anal. Calc. for C80H104N8O8S16Zn: C, 51.00; H, 5.56; N, 5.95; S, 27.23%. Found: C, 51.19; H, 5.90; N, 6.10; S, 27.30. IR (KBr tablet) mmax/cm 1: 3436 (O–H), 3065 (Ar–H), 2914–2835 (Aliph. C–H), 1646, 1598, 1479, 1415, 1281, 1224, 1182, 1122, 1070, 1023, 829, 747. 1HNMR. (CDCl3), (d:ppm): 8.06 (d, 4H, Ar–H), 7.84 (s, 4H, Ar–H), 7.46 (d, 4H, Ar–H), 5.17 (br, 4H, O-H), 4.88 (m, 4H, CH–O), 3.74 (m, 4H, CH–OH), 3.34–2.67 (m, 64H, CH2–S), 1.86 (m, 16H, CH2). UV–vis (chloroform): kmax/nm: [(10–5 e dm3 mol–1 cm–1)]: 311 (5.15), 353 (5.13), 620 (4.63), 689 (5.19). MS (ES+), (m/z): 1884 [M]+. Synthesis of cobalt(II) phthalocyanine 7: The same procedure as above was adopted by using compound 3 (0.35 g, 0.76 mmol), anhydrous CoCl2 (25 mg 0.19 mmol) and 2-(dimethylamino)ethanol (2.5 ml). The solid product was purified by preparative thin layer chromatography (TLC) using chloroform/ petroleum ether/methanol (8.5:1.5:1) solvent system. This compound is soluble in CHCl3, CH2Cl2, CH3COCH3 (acetone), THF, DMF, DMSO. Yield: 246 mg (69%), mp > 260–262 °C. Anal. Calc. for C80H104CoN8O8S16: C, 51.17; H, 5.58; N, 5.97; S, 27.32%. Found: C, 51.20; H, 5.85; N, 5.90; S, 27.28. IR (KBr tablet) mmax/cm 1: 3401 (O-H), 3060 (Ar–H), 2911–2851 (Aliph. C–H), 1606, 1514, 1475, 1410, 1319, 1273, 1225, 1122, 1093, 1060, 1017, 949, 753. 1H NMR. (CDCl3), (d:ppm): 8.00 (d, 4H, Ar–H), 7.80 (s, 4H, Ar–H), 7.43 (d, 4H, Ar– H), 5.18 (br, 4H, O–H), 4.91 (m, 4H, CH–O), 3.75 (m, 4H, CH–OH), 3.34–2.60 (m, 64H, CH2-S), 1.89 (m, 16H, CH2). UV–vis (chloroform): kmax/nm: [(10–5 e dm3 mol–1 cm–1)]: 302 (5.10), 357 (5.08), 614 (4.70), 683 (5.16). MS (ES+), (m/z): 1880 [M + 2]+. Synthesis of copper(II) phthalocyanine 8: The same procedure as above was adopted by using compound 3 (0.35 g, 0.76 mmol), anhydrous CuCl2 (26 mg 0.19 mmol) and 2-(dimethylamino)ethanol (2.5 ml). The solid product was purified by preparative thin layer chromatography (TLC) using chloroform/ petroleum ether/methanol (7:2:1) solvent system. This compound is soluble in CHCl3, CH2Cl2, CH3COCH3 (acetone), THF, DMF, DMSO. Yield: 225 mg (63%), mp > 218–220 °C. Anal. Calc. for C80H104CuN8O8S16: C, 51.05; H, 5.57; N, 5.95; S, 27.26%. Found: C, 51.16; H, 5.71; N, 5.88; S, 27.12. IR (KBr tablet) mmax/cm 1: 3447 (O–H), 3071 (Ar–H), 2915–2846 (Aliph. C–H), 1599, 1487, 1410, 1311, 1252, 1227, 1120, 1091, 995, 838. UV–vis(chloroform): kmax/nm: [(10–5 e dm3 mol–1 cm–1)]: 295 (5.11), 361 (5.09), 617 (4.68), 689(5.15). MS (ES+), (m/z): 1882 [M]+. Synthesis of lead(II) phthalocyanine 9: The same procedure as above was adopted by using compound 3 (0.35 g, 0.76 mmol), anhydrous PbO (42 mg 0.19 mmol) and 2-(dimethylamino)ethanol (2.5 ml). The solid product was purified by preparative thin layer chromatography (TLC) using chloroform/ petroleum ether/methanol (7:2:1) solvent system. This compound is soluble in CHCl3, CH2Cl2, CH3COCH3 (acetone), THF, DMF, DMSO. Yield: 223 mg (58%), mp > 300 °C. Anal. Calc. for C80H104N8O8PbS16: C, 47.43; H, 5.17; N, 5.53; S, 27.32%. Found: C, 47.05; H, 5.35; N, 5.60; S, 27.40. IR (KBr tablet) mmax/cm 1: 3468 (O–H), 3065 (Ar–H), 2915–2852 (Aliph. C–H), 1600, 1484, 1415, 1318, 1253, 1085, 999, 845, 687. 1H NMR. (CDCl3), (d:ppm): 8.10 (d, 4H, Ar–H), 7.89 (s, 4H, Ar–H), 7.51 (d, 4H, Ar–H), 5.22 (br, 4H, O–H), 4.94 (m, 4H, CH–O), 3.73 (m, 4H, CH–OH), 3.35–2.69 (m, 64H, CH2-S), 1.91 (m, 16H, CH2). UV–vis (chloroform): kmax/nm: [(10–5 e dm3 mol–1 cm–1)]: 299 (5.15), 365 (5.13), 653 (4.62), 728 (5.26). MS (ES+), (m/z): 2025 [M]+. C.F. Van Nostrum, S.J. Picken, A.J. Schouten, R.J.M. Nolte, J. Am. Chem. Soc. 117 (1995) 9957. Y. Agnus, R. Louis, JP. Gisselbrecht, R. Weiss, J. Am. Chem. Soc. 106 (1984) 93. A.E. Martin, J.E. Bulkowski, J. Org. Chem. 47 (1982) 415. J.M. Lehn, Pure Appl. Chem. 52 (1980). K. Takahashi, M. Kawashima, Y. Tomita, M. Itoh, Inorg. Chim. Acta 232 (1995) 69.
Contents lists available at ScienceDirect
Inorganic Chemistry Communications journal homepage: www.elsevier.com/locate/inoche
Microwave-assisted synthesis and characterization of new soluble metal-free and metallophthalocyanines substituted with four tetrathiamacrocycles through oxy bridges _ Zekeriya Bıyıklıog˘lu, Irfan Acar, Halit Kantekin * Department of Chemistry, Faculty of Arts and Sciences, Karadeniz Technical University, 61080 Trabzon, Turkey
a r t i c l e
i n f o
Article history: Received 15 January 2008 Accepted 22 February 2008 Available online 4 March 2008
Keywords: Tetrathiamacrocycles Metallophthalocyanine Synthesis Microwave Phthalonitrile
a b s t r a c t The new soluble metal-free and Ni(II), Zn(II), Co(II), Cu(II), Pb(II) phthalocyanines with four, tetrathiamacrocycles were obtained from 4-[(11-hyroxy-1,5,9,13-tetrathiacyclohexadecan-3-yl)oxy]phthalonitrile 3 and the corresponding divalent metal salt (NiCl2, Zn(CH3COO)2, CoCl2, CuCl2 and PbO). Metal-free and metallophthalocyanines showed the enhanced solubility in organic solvents. The structures of the target compounds were confirmed using elemental analysis, IR, 1H NMR, 13C NMR, UV–vis and MS spectral data. Ó 2008 Elsevier B.V. All rights reserved.
Metal-free and metallophthalocyanines have enjoyed considerable industrial importance for use in dyestuffs, paints, colors for metal surfaces, fabrics and plastics. Meanwhile, chemical and physical studies of metal Pcs and their derivatives are also pursued by worldwide chemists for their potential applications in many areas. The functions of metal-free and metal Pcs and their derivatives are almost based on a redox or electron transfer reaction [1–3]. Applications of phthalocyanines are limited due to their insolubility in common organic solvents and water [4,5]. Phthalocyanines possess an extended p-conjugated electron system which permits p-stacking between planar macrocycles provided the distance between the macrocycles is sufficiently small [4]. Adding substituents to the periphery of the macrocycles increases their solubility since these substituents increase the distance between the stacked phthalocyanines and enable their solvation [6,7]. Phthalocyanine complexes are capable of binding alkali metal ions and provide donor sites for binding transition metal ions, leading to homo- and heteronuclear complexes. As donors, thioether moieties can be placed between oxa and aza groups for their tendency to complex with alkali and transition metal ions [8,9]. However, phthalocyanines with N- and O-donor substituents are frequently encountered, those with thioether moieties are rather rare [10,11]. A literature survey [12–16] shows that most * Corresponding author. Tel.: +90 462 377 2589; fax: +90 462 325 3196. E-mail address: [email protected] (H. Kantekin). 1387-7003/$ - see front matter Ó 2008 Elsevier B.V. All rights reserved. doi:10.1016/j.inoche.2008.02.030
of the recent work on thioether-substituted phthalocyanines has been patented for applications as IR absorbers [17]. We have previously synthesized phthalocyanines by microwave irradiation [18–23]. The present paper describes the preparation of new soluble metal-free and metallophthalocyanines carrying four 16-membered tetrathiamacrocycles with oxy bridges. The synthetic routes to 3–9 are summarized in Scheme 1. The original precursor compound 3 [24] for the synthesis of phthalocyanines was obtained by nitro displacement reaction of compounds 1 [25] and 2 [26] using K2CO3 as a catalyst in DMF by stirring at room temperature. Cyclotetramerization of macrocyclic dicyano derivative 3 with anhydrous metal salts (NiCl2, Zn(CH3COO)2, CoCl2, CuCl2 and PbO) and 2-(dimethylamino)ethanol at 175 °C, 350 W in microwave oven led to the formation of metal-free and metallophthalocyanines. In the IR spectrum of 3, stretching vibrations of O–H, aromatic and aliphatic CH, nitrile (C„N) groups were observed at 3435, 3071, 2923–2846 and 2230 cm 1, respectively. In addition, comparison of the IR spectrum of compound 3 and 4-nitrophthalonitrile 2 gave support for the proposed structure. These indicated the formation of 3 by the disappearance of the NO2 band of 4-nitrophthalonitrile at 1538 cm 1 and the appearance of new absorptions at 1092–1020 cm 1 belonging to ether group. 1H NMR spectrum of 3 showed new signals at d = 7.76 (d, 1H, Ar-H), 7.34 (s, 1H, Ar-H), 7.24 (d, 1H, Ar–H) belonging to aromatic protons. The 13C NMR spectrum of 3 indicated the presence of nitrile carbon atoms in 3 at d = 115.51 and 115.14 ppm. The MS spectrum of compound 3
Z. Bı yı klı og˘lu et al. / Inorganic Chemistry Communications 11 (2008) 630–632
631
CN S
S
S
S
HO
CN OH O2N
CN
dry DMF dry K2CO3
S
S
S
S
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CN
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1
DMAE MW
OH
HO S
S S
S
S
S S
S O
O
N N
N N
N
M N
N N
O
O
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S S
S
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4
5
6
7
8
9
2H Ni Zn Co Cu Pb
Scheme 1. The synthesis of the metal-free phthalocyanine and metallophthalocyanines.
bands, one of them in the visible region at about 614–728 nm corresponding to the Q band, and the other in the UV, approximately at 300 nm. The split Q bands in 4, which are characteristic for metal-free phthalocyanines were observed at kmax = 710, 674, 647 and 614 nm. These Q band absorptions show the monomeric species with D2h symmetry and due to the phthalocyanine ring related to the fully conjugated 18 p-electron system [34–36]. The presence of strong absorption bands in 4 in the near UV region at kmax = 345 and 295 nm also shows Soret region B bands which have been ascribed to the deeper p–p* levels of LUMO transitions (see Fig. 1).
2
10-5 ε / dm3 mol-1cm-1
displayed the [M + Na]+ parent ion peak at m/z = 477, which confirms the same structure. The IR spectra of metal-free 4 [27] and metallophthalocyanines 5–9 [28–32] are very similar. A diagnostic feature of the formation of compound 4 from dinitrile 3 is the disappearance of the sharp C„N vibration at 2230 cm 1. The stretching vibrations at 3285 cm 1 for compound 4 can be attributed to the N–H band of the inner core of the metal-free phthalocyanine. The 1H NMR spectrum of compound 4 indicates the aromatic protons at d 8.01, 7.82, 7.45, broad O–H proton at d 5.12 and the aliphatic ether protons at d 4.88–1.81 ppm. The inner core protons (N–H) of this compound 4 could not be observed because of the probable strong aggregation of the molecule [33,20]. The mass spectrum of this compound 4 at m/z = 1820 [M]+ lends support to the proposed formula for this structure. In the IR spectra of metallophthalocyanines 5–9, cyclotetramerization of dinitriles 3 to Pcs 5–9 was confirmed by the disappearance of the sharp –C„N vibration at 2230 cm 1. The 1H NMR spectra of metal-free 4, nickel(II) 5, zinc(II) 6, cobalt(II) 7 and lead(II) 9 phthalocyanines are almost identical. 1H NMR measurement of the copper(II) phthalocyanine 8 was precluded owing to its paramagnetic nature. In the mass spectrum of Ni(II), Zn(II), Co(II), Cu(II) and Pb(II) phthalocyanines, the presence of molecular ion peaks at m/z = 1878 [M + 1]+, 1884 [M]+, 1880 [M + 2]+, 1882 [M]+ and 2025 [M]+, respectively, confirmed the proposed structures. Elemental analysis data were satisfactory. Metal-free phthalocyanine 4 and metallophthalocyanines 5–9 showed typical UV-visible spectra with two significant absorption
1.5
1
0.5
0 200
300
400
500
600
700
800
900
λ ( nm ) Fig. 1. UV–vis spectra of compounds 4 (–), 5 (—) and 6 (. . .) in chloroform.
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Z. Bı yı klı og˘lu et al. / Inorganic Chemistry Communications 11 (2008) 630–632
Metallophthalocyanines 5–9 showed the expected absorptions at the main peaks of the Q- and B-bands appearing at kmax = 683, 689, 683, 689, 728 nm and 300, 311, 302, 295, 299 nm, respectively. This result is typical of metal complexes of substituted and unsubstituted Pcs with D4h symmetry [37]. Usually, peripheral tetra-substituted phthalocyanines are a mixture of four constitutional isomers (with C4h, D2h, C2v and Cs symmetry).
[28]
Acknowledgement This study was supported by the Research Fund of Karadeniz Technical University, project no: 2006.111.002.1 (Trabzon-Turkey). References [29] [1] A. Gouloumis, T. Torres, Org. Lett. 1 (1999) 1807. [2] P. Ka-Wo, Y. Yan, L. Xi-You, KPNg. Dennis, Organometallics 18 (1999) 3528. [3] T. Fukuda, EA. Makarova, EA. Lukyanets, N. Kobayashi, Chem-A Eur. J. 10 (2004) 117. [4] M. Hanack, M. Lang, Adv. Mater. 6 (1994) 819. [5] W. Eberhardt, M. Hanack, Synthesis 1 (1997) 95. [6] Ö. Bekarog˘lu, J. Porp. Phthalocyan. 4 (2000) 465. [7] P. Haisch, M. Hanack, Synthesis 10 (1995) 1251. [8] S.G. Murray, F.R. Hartley, Chem. Rev. 81 (1981) 365. [9] S. Dabak, A.G. Gürek, E. Musluog˘lu, V. Ahsen, New J. Chem. 25 (2001) 1583. [10] W.A. Snow, J.R. Griffith, Macromolecules 17 (1984) 1614. [11] D. Wöhrle, G. Schnurpfeil, G. Knothe, Dyes Pigments 18 (1992) 91. [12] I. Cho, Y. Lim, Mol. Cryst. Liq. Cryst. 154 (1988) 9. [13] A. Lux, GG. Rozenberg, K. Petritsch, S.C. Moratti, A.B. Holmes, R.H. Friend, Synth. Met. 102 (1999) 1527. [14] H. Eichorn, D. Wöhrle, D. Pressner, Liq. Cryst. 22 (1997) 643. [15] K. Ban, K. Nishizawa, K. Ohta, H. Shirari, J. Mater. Chem. 10 (2000) 1083. [16] AG. Gürek, V. Ahsen, D. Luneau, J. Pecaut, Inorg. Chem. 40 (2001) 4793. [17] PJ. Duggan, PF. Gordon, Eur. Pat. 1 (1985) 55780. [18] Z. Bıyıklıog˘lu, H. Kantekin, M. Özil, J. Organomet. Chem. 692 (2007) 2436. [19] Z. Bıyıklıog˘lu, H. Kantekin, Transit. Met. Chem. 32 (2007) 851. [20] H. Kantekin, Z. Bıyıklıog˘lu, Dyes Pigments 77 (2008) 98. [21] H. Kantekin, Z. Bıyıklıog˘lu, Dyes Pigments 77 (2008) 432. [22] Z. Bıyıklıog˘lu, H. Kantekin, J. Organomet. Chem. 693 (2008) 505. [23] H. Kantekin, G. Dilber, Z. Bıyıklıog˘lu, J. Organomet. Chem. 693 (2008) 1038. [24] Synthesis of 4-[(11-hydroxy-1,5,9,13-tetrathiacyclohexadecan-3-yl)oxy] phthalonitrile 3: 1,5,9,13-tetrathiacyclohexadecane-3,11-diol 1 (2 g, 6.0 mmol) was dissolved in anhydrous DMF (40 ml) under N2 atmosphere and 4-nitrophthalonitrile 2 (1.03 g, 6.0 mmol) was added to the solution. After stirring for 15 min, at room temperature, dry fine-powdered potassium carbonate (3.31 g, 24.0 mmol) was added portionwise within 2 h with efficient stirring. The reaction mixture was stirred under N2 at room temperature for 4 days. The reddish-brown mixture was extracted with chloroform (25 ml). The organic layer was separated, washed with water and then dried over Na2SO4. After evaporation of the solvent the product was crystallized from ethanol as pale yellow crystals. Yield: 2.04 g (74%), mp: 92 °C. Anal. Calc. for C20H26N2O2S4: C, 52.83; H, 5.76; N, 6.16; S, 28.21%. Found: C, 52.80; H, 5.97; N, 6.09; S, 28.46. IR (KBr tablet), mmax/cm 1: 3435 (O–H), 3071 (Ar–H), 2923–2846 (Aliph. C–H), 2230 (C–N), 1592, 1558, 1497, 1413, 1317, 1256, 1168, 1092, 1020, 989, 852, 525. 1H NMR. (CDCl3), (d:ppm): 7.76 (d, 1H, Ar–H), 7.34 (s, 1H, Ar–H), 7.24 (d, 1H, Ar–H), 4.66 (m, 1H, CH–O), 3.90 (m, 1H, CH–OH), 3.04–2.62 (m, 16H, CH2–S), 1.96 (m, 4H, CH2), 1.62 (br, 1H, O–H). 13C NMR. (CDCl3), (d:ppm): 160.75, 135.46, 120.73, 120.27, 117.68, 115.51, 115.14, 107.96, 78.75, 78.67, 40.58, 38.12, 34.71, 31.68, 29.36. MS (ES+), (m/z): 477 [M + Na]+. [25] V.B. Pett, G.H. Leggett, T.H. Cooper, P.R. Reed, D. Situmeang, L.A. Ochrymowycz, D.B. Rorabacher, Inorg. Chem. 27 (1988) 2164. [26] G.J. Young, W. Onyebuagu, J. Org. Chem. 55 (1990) 2155. [27] Synthesis of metal-free phthalocyanine 4: 4-[(11-hydroxy-1,5,9,13tetrathiacyclohexadecan-3-yl)oxy]phthalonitrile 3 (0.35 g, 0.76 mmol) was ground together in a microwave oven and 2-(dimethylamino)ethanol (3.0 ml) was added. The reaction mixture was irradiated in microwave reaction oven at 175 °C, 350 W for 8 min. After being cooled, the reaction mixture was poured into 25 ml of ethanol and the dark green precipitate that formed was separated by filtration. The crude metal-free phthalocyanine mixture was washed with ethanol, water, diethyl ether and then dried in vacuum. The solid product was purified by preparative thin layer chromatography (TLC) using chloroform solvent system. This compound is soluble in CHCl3, CH2Cl2, CH3COCH3 (acetone), THF, DMF, DMSO. Yield: 189 mg (55%), mp > 198– 200 °C. Anal. Calc. for C80H106N8O8S16: C, 52.77; H, 5.87; N, 6.15; S, 28.18%. Found: C, 52.85; H, 6.0; N, 6.40; S, 28.29. IR (KBr tablet) mmax/cm 1: 3400 (O– H), 3285 (N–H), 3060 (Ar–H), 2910–2846 (Aliph. C–H), 1606, 1475, 1417, 1316, 1230, 1094, 1013, 821, 744. 1H NMR. (CDCl3), (d:ppm): 8.01 (d, 4H, Ar–H), 7.82
[30]
[31]
[32]
[33] [34] [35] [36] [37]
(s, 4H, Ar–H), 7.45 (d, 4H, Ar–H), 5.12 (br, 4H, O–H), 4.88 (m, 4H, CH–O), 3.70 (m, 4H, CH–OH), 3.36–2.61 (m, 64H, CH2-S), 1.81 (m, 16H, CH2). UV–vis (chloroform): kmax/nm: [(10 5 e dm3 mol 1 cm 1)]: 295 (5.11), 345 (5.08), 614 (4.66), 647 (4.83), 674 (5.22), 710 (5.29). MS (ES+), (m/z): 1820 [M]+. Synthesis of nickel(II) phthalocyanine 5: The same procedure as above was adopted by using compound 3 (0.35 g, 0.76 mmol), anhydrous NiCl2 (25 mg 0.19 mmol) and 2-(dimethylamino)ethanol (2.5 ml). The solid product was purified by preparative thin layer chromatography (TLC) using chloroform/ methanol (9:1) solvent system. This compound is soluble in CHCl3, CH2Cl2, CH3COCH3 (acetone), THF, DMF, DMSO. Yield: 231 mg (64%), mp > 255– 257 °C. Anal. Calc. for C80H104N8NiO8S16: C, 51.18; H, 5.58; N, 5.97; S, 27.33%. Found: C, 51.00; H, 5.86; N, 5.80; S, 27.40. IR (KBr tablet) mmax/cm 1: 3417 (O–H), 3060 (Ar–H), 2912–2835 (Aliph. C–H), 1606, 1475, 1412, 1227, 1119, 1089, 1061, 952, 834. 1HNMR. (CDCl3), (d:ppm): 8.08 (d, 4H, Ar–H), 7.90 (s, 4H, Ar–H), 7.54 (d, 4H, Ar–H), 5.24 (br, 4H, O–H), 4.96 (m, 4H, CH–O), 3.78 (m, 4H, CH–OH), 3.37–2.65 (m, 64H, CH2–S), 1.88 (m, 16H, CH2). UV–vis (chloroform): kmax/nm: [(10–5 e dm3 mol–1 cm–1)]: 300 (5.07), 350 (5.05), 614 (4.67), 683 (5.15). MS (ES+), (m/z): 1878 [M + 1]. Synthesis of zinc(II) phthalocyanine 6: The same procedure as above was adopted by using compound 3 (0.35 g, 0.76 mmol), anhydrous Zn(CH3COO)2 (35 mg, 0.19 mmol) and 2-(dimethylamino)ethanol (2.5 ml). The solid product was purified by preparative thin layer chromatography (TLC) using chloroform/petroleum ether/methanol (8:1:1) solvent system. This compound is soluble in CHCl3, CH2Cl2, CH3COCH3 (acetone), THF, DMF, DMSO. Yield: 215 mg (60%), mp > 230–232 °C. Anal. Calc. for C80H104N8O8S16Zn: C, 51.00; H, 5.56; N, 5.95; S, 27.23%. Found: C, 51.19; H, 5.90; N, 6.10; S, 27.30. IR (KBr tablet) mmax/cm 1: 3436 (O–H), 3065 (Ar–H), 2914–2835 (Aliph. C–H), 1646, 1598, 1479, 1415, 1281, 1224, 1182, 1122, 1070, 1023, 829, 747. 1HNMR. (CDCl3), (d:ppm): 8.06 (d, 4H, Ar–H), 7.84 (s, 4H, Ar–H), 7.46 (d, 4H, Ar–H), 5.17 (br, 4H, O-H), 4.88 (m, 4H, CH–O), 3.74 (m, 4H, CH–OH), 3.34–2.67 (m, 64H, CH2–S), 1.86 (m, 16H, CH2). UV–vis (chloroform): kmax/nm: [(10–5 e dm3 mol–1 cm–1)]: 311 (5.15), 353 (5.13), 620 (4.63), 689 (5.19). MS (ES+), (m/z): 1884 [M]+. Synthesis of cobalt(II) phthalocyanine 7: The same procedure as above was adopted by using compound 3 (0.35 g, 0.76 mmol), anhydrous CoCl2 (25 mg 0.19 mmol) and 2-(dimethylamino)ethanol (2.5 ml). The solid product was purified by preparative thin layer chromatography (TLC) using chloroform/ petroleum ether/methanol (8.5:1.5:1) solvent system. This compound is soluble in CHCl3, CH2Cl2, CH3COCH3 (acetone), THF, DMF, DMSO. Yield: 246 mg (69%), mp > 260–262 °C. Anal. Calc. for C80H104CoN8O8S16: C, 51.17; H, 5.58; N, 5.97; S, 27.32%. Found: C, 51.20; H, 5.85; N, 5.90; S, 27.28. IR (KBr tablet) mmax/cm 1: 3401 (O-H), 3060 (Ar–H), 2911–2851 (Aliph. C–H), 1606, 1514, 1475, 1410, 1319, 1273, 1225, 1122, 1093, 1060, 1017, 949, 753. 1H NMR. (CDCl3), (d:ppm): 8.00 (d, 4H, Ar–H), 7.80 (s, 4H, Ar–H), 7.43 (d, 4H, Ar– H), 5.18 (br, 4H, O–H), 4.91 (m, 4H, CH–O), 3.75 (m, 4H, CH–OH), 3.34–2.60 (m, 64H, CH2-S), 1.89 (m, 16H, CH2). UV–vis (chloroform): kmax/nm: [(10–5 e dm3 mol–1 cm–1)]: 302 (5.10), 357 (5.08), 614 (4.70), 683 (5.16). MS (ES+), (m/z): 1880 [M + 2]+. Synthesis of copper(II) phthalocyanine 8: The same procedure as above was adopted by using compound 3 (0.35 g, 0.76 mmol), anhydrous CuCl2 (26 mg 0.19 mmol) and 2-(dimethylamino)ethanol (2.5 ml). The solid product was purified by preparative thin layer chromatography (TLC) using chloroform/ petroleum ether/methanol (7:2:1) solvent system. This compound is soluble in CHCl3, CH2Cl2, CH3COCH3 (acetone), THF, DMF, DMSO. Yield: 225 mg (63%), mp > 218–220 °C. Anal. Calc. for C80H104CuN8O8S16: C, 51.05; H, 5.57; N, 5.95; S, 27.26%. Found: C, 51.16; H, 5.71; N, 5.88; S, 27.12. IR (KBr tablet) mmax/cm 1: 3447 (O–H), 3071 (Ar–H), 2915–2846 (Aliph. C–H), 1599, 1487, 1410, 1311, 1252, 1227, 1120, 1091, 995, 838. UV–vis(chloroform): kmax/nm: [(10–5 e dm3 mol–1 cm–1)]: 295 (5.11), 361 (5.09), 617 (4.68), 689(5.15). MS (ES+), (m/z): 1882 [M]+. Synthesis of lead(II) phthalocyanine 9: The same procedure as above was adopted by using compound 3 (0.35 g, 0.76 mmol), anhydrous PbO (42 mg 0.19 mmol) and 2-(dimethylamino)ethanol (2.5 ml). The solid product was purified by preparative thin layer chromatography (TLC) using chloroform/ petroleum ether/methanol (7:2:1) solvent system. This compound is soluble in CHCl3, CH2Cl2, CH3COCH3 (acetone), THF, DMF, DMSO. Yield: 223 mg (58%), mp > 300 °C. Anal. Calc. for C80H104N8O8PbS16: C, 47.43; H, 5.17; N, 5.53; S, 27.32%. Found: C, 47.05; H, 5.35; N, 5.60; S, 27.40. IR (KBr tablet) mmax/cm 1: 3468 (O–H), 3065 (Ar–H), 2915–2852 (Aliph. C–H), 1600, 1484, 1415, 1318, 1253, 1085, 999, 845, 687. 1H NMR. (CDCl3), (d:ppm): 8.10 (d, 4H, Ar–H), 7.89 (s, 4H, Ar–H), 7.51 (d, 4H, Ar–H), 5.22 (br, 4H, O–H), 4.94 (m, 4H, CH–O), 3.73 (m, 4H, CH–OH), 3.35–2.69 (m, 64H, CH2-S), 1.91 (m, 16H, CH2). UV–vis (chloroform): kmax/nm: [(10–5 e dm3 mol–1 cm–1)]: 299 (5.15), 365 (5.13), 653 (4.62), 728 (5.26). MS (ES+), (m/z): 2025 [M]+. C.F. Van Nostrum, S.J. Picken, A.J. Schouten, R.J.M. Nolte, J. Am. Chem. Soc. 117 (1995) 9957. Y. Agnus, R. Louis, JP. Gisselbrecht, R. Weiss, J. Am. Chem. Soc. 106 (1984) 93. A.E. Martin, J.E. Bulkowski, J. Org. Chem. 47 (1982) 415. J.M. Lehn, Pure Appl. Chem. 52 (1980). K. Takahashi, M. Kawashima, Y. Tomita, M. Itoh, Inorg. Chim. Acta 232 (1995) 69.