Photophysical and photochemical properties of novel metallophthalocyanines bearing 7-oxy-3-(m-methoxyphenyl)coumarin groups

Author’s Accepted Manuscript Photophysical and photochemical properties of novel metallophthalocyanines bearing 7-oxy-3-(mmethoxyphenyl)coumarin groups Ayşegül Taştemel, Birsen Yılmaz Karaca, Mahmut Durmuş, Mustafa Bulut www.elsevier.com/locate/jlumin

PII: DOI: Reference:

S0022-2313(15)00430-5 http://dx.doi.org/10.1016/j.jlumin.2015.07.050 LUMIN13500

To appear in: Journal of Luminescence Received date: 10 March 2015 Revised date: 23 June 2015 Accepted date: 28 July 2015 Cite this article as: Ayşegül Taştemel, Birsen Yılmaz Karaca, Mahmut Durmuş and Mustafa Bulut, Photophysical and photochemical properties of novel metallophthalocyanines bearing 7-oxy-3-(m-methoxyphenyl)coumarin groups, Journal of Luminescence, http://dx.doi.org/10.1016/j.jlumin.2015.07.050 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting galley proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

Photophysical and photochemical properties of novel metallophthalocyanines bearing 7oxy-3-(m-methoxyphenyl)coumarin groups Ayşegül Taştemela, Birsen Yılmaz Karacaa,Mahmut Durmuşb and Mustafa Buluta* a

Marmara University, Faculty of Art and Science, Department of Chemistry, 34722 Kadıkoy-Istanbul, Turkey b

Gebze Technical University, Department of Chemistry, P.O. Box 141, Gebze 41400, Kocaeli, Turkey

Corresponding author. M. Bulut. Tel: +90-216-3479641 / 1370; Fax: +90-216-3478783,e-mail address: [email protected]

1

Abstract Tetra peripherally and non-peripherally 7-oxy-3-(m-methoxyphenyl)coumarin-substituted zinc(II) (4a and 5a), indium(III)acetate (4b and 5b) and magnesium(II) (4c and 5c) phthalocyanines were synthesized for the first time. These phthalocyanines were characterized by elemental analysis, FT-IR, 1H-NMR, UV-vis spectroscopy and mass spectra. The novel phthalocyanines showed excellent solubility in general organic solvents, such as dichloromethane, chloroform, tetrahydrofuran (THF), N,N-dimethylformamide (DMF) and dimethylsulfoxide (DMSO). The photophysical and photochemical properties of these phthalocyanines were investigated in DMF. The effects of the central metal ions (Zn2+, Mg2+, In+3) and the position (peripheral or nonperipheral) of the substituents on the photophysical and photochemical parameters were reported for comparison. The singlet oxygen quantum yield values of novel phthalocyanines ranged from 0.29 to 0.82 in DMF. In this study, the fluorescence quenching behavior of the studied zinc(II) and magnesium(II) phthalocyanine complexes were also described by the addition of 1,4benzoquinone.

Keywords:

Phthalocyanine;

Coumarin

(2H-chromen-2-one,

Fluorescence; Quantum yield; Singlet oxygen; Quenching. 2

2H-1-benzopyran-2-one);

1. Introduction Coumarin (2H-chromen-2-one, 2H-1-benzopyran-2-one) derivatives are naturally occurring benzopyrane derivatives. They display a wide range of biological activities [1]. Furthermore, they extend optical properties, such as prominent spectral range, large Stokes shifts, high quantum yields, and superior photostability and solubility in common organic solvents [2]. On the other hand, 3-phenylcoumarin derivatives are potent antioxidant, antimicrobial [3], antiviral [4], antidepressant [5], anticoagulant [6], and vasorelaxant [7] compounds, along with the ability to inhibit peroxidases, lipoxygenase [8,9] and monoamine oxidase enzyme (MAO-B) [10]. Phthalocyanines are aromatic macrocycles based on an extensive delocalized 18 electron system. They play a major role in many fields of modern technology such as data storage, photoelectronic generation, and catalyst [11-12]. Their use as photosensitizers in photodynamic therapy (PDT) is the most attractive application of phthalocyanines because of their ability to generate highly singlet oxygen (1O2), which is toxic for tumor cells [13-15]. However, there are two principal disadvantages of phthalocyanines based on photosensitizers: one of them is low solubility and another one is the tendency to aggregate. Peripheral substitution of the macrocyclic ring with a bulky group leads to phthalocyanine products, which are soluble in common organic solvents. Substitutions of the macrocyclic ring at more sterically crowded nonperipheral positions result less aggregated species than substitutions at peripheral positions [1618]. The photophysical and photochemical properties of the phthalocyanine dyes are strongly influenced by the presence and nature of the central metal ion. The presence of diamagnetic metal ions such as Zn2+ or Mg2+ in the phthalocyanine core results in large triplet state quantum yields, 3

leading to the generation of higher concentration of singlet oxygen, hence improved PDT activity [19]. Indium is also a useful central metal ion in metallophthalocyanine complexes since it is diamagnetic and able to host axial ligands. Excellent photosensitizing and optical limiting properties have been reported for indium phthalocyanines [19-25]. In our previous work, 7-oxy-3-(4-methoxyphenyl)coumarin bearing zinc phthalocyanines were reported as potential photosensitizers in PDT applications [26]. The aim of our present research is to synthesize soluble phthalocyanine agents substituted with 7-oxy-3-(mmethoxyphenyl)coumarin moieties, which may inhibit the increased activity of MAO-B enzyme in the Parkinson’s disease [27], bearing zinc(II), indium(III) and magnesium(II) as central metal ions in the cavity for potential PDT. In this study, the effect of the nature of the central metal ions (Zn2+, Mg2+, In+3) and the position of the substituents (peripheral or non-peripheral) on the photophysical and photochemical parameters were investigated. Since PDT activity is mainly based on singlet oxygen, its production was determined by the dye-sensitized photooxidation of 1,3-diphenylisobenzofuran (DPBF), which is a specific scavenger of this toxic species [28]. 2. Experimental 2.1. Materials and equipment Zinc(II) acetate dihydrate, magnesium(II) acetate tetrahydrate, indium(III) acetate, potassium carbonate and unsubstituted zinc phthalocyanine were purchased from the Aldrich. 1,3Diphenylisobenzofuran (DPBF) and 3-methoxyphenylacetic acid were purchased from Fluka. All solvents were dried as described by Perrin and Armarego [29]. 7-Hydroxy-3-(mmethoxyphenyl)coumarin [30], 3-nitrophthalonitrile [31] and 4-nitrophthalonitril [32] were 4

synthesized and purified according to the well-known literatures. Absorption spectra in the UV-visible region were recorded on a Shimadzu UV-2450UVvisible spectrophotometer. Fluorescence excitation and emission spectra were recorded on a Varian Eclipse spectrofluorometer using 1 cm path length cuvette at room temperature. FT-IR spectra were recorded on a Perkin Elmer Spectrum 100 FT-IR spectrophotometer. 1H NMR spectra were recorded on a Varian Unity Inova 500 MHz spectrometer using TMS as an internal standard. Mass spectra were performed on BRUKER MICROFLEX LT MALDI-TOF spectrophotometer using 2,5-dihydroxybenzoic acid (DHB, 0.02 g/cm 3 in chloroform) as matrix. Photoirradiations were done using a General Electric quartz line lamp (300W). A 600 nm glass cut off filter (Schott) and a water filter were used to filter off ultraviolet and infrared radiations, respectively. An interference filter (Intor, 670 nm with a band with of 40 nm) was additionally placed in the light path before the sample. Light intensities were measured with a POWER MAX5100 (Molelectron detector incorporated) power meter. 2.2. Synthesis 2.2.1. 4-[3-(m-methoxyphenyl)-2-oxo-2H-chromen-7-yloxy]phthalonitrile(4) 0.64 g (2.4 mmol) 7-Hydroxy-3-(m-methoxyphenyl)coumarin (1) and 0.41 g (2.4 mmol) 4nitrophthalonitrile (2) were dissolved in 20 mL anhydrous DMF under argon atmosphere and 0.5 g (3.6 mmol) anhydrous K2CO3 was added to this solution during 2 h. After stirring under argon atmosphere at 650C for 72 h, the reaction mixture was cooled to room temperature. The reaction mixture was poured into cold water and the formed precipitate was filtered. The obtained solid product was washed with water and then dried. The crude product was purified by column chromatography on silica gel using chloroform as eluent. The obtained pale-yellow compound is 5

soluble in dichloromethane, THF, chloroform, DMF and DMSO. Yield: 0.6 g (64%). Mp.: 2010C. FT-IR γmax(cm-1): 3073-3037 (Ar-CH), 2941-2840 (Aliphatic CH), 2227 (-CN), 1711 (C=O lactone), 1582 (C=C), 1276 (Ar-O-Ar). 1H NMR (CDCl3), ppm: Aromatic protons: 8.14 (d, 8.67 Hz, 1H), 7.92 (d, 2.55 Hz, 1H), 7.86 (d, 8.55 Hz, 1H), 7.56 (dd, 8.79 Hz and 2.59 Hz, 1H), 7.37 (dd, 7.7 Hz and 8 Hz, 1H), 7.30 (d, 2.40 Hz, 1H), 7.29 ( d, 8.28 Hz, 1H), 7.28 (dd, 2.58 Hz and 2.54 Hz, 1H), 7.18 (dd, 8.48 Hz and 2.57 Hz, 1H), 6.99 (dd, 8.23 Hz and 2.59 Hz, 1H), lactone proton: 8.30 (s, 1H, CH), aliphatic protons: 3.80 (s, 3H, -OCH3). Anal. Calc. for C24H14N2O4 (394.38): C, 73.09; H, 3.58; N, 7.10%; Found: C,72.97; H, 3.44; N, 6.93 %. MS (MALDI-TOF) m/z: 394.406 [M]+. 2.2.2. 3-[3-(m-methoxyphenyl)-2-oxo-2H-chromen-7-yloxy]phthalonitrile(5) 0.45 g (1.6 mmol) 7-Hydroxy-3-(m-methoxyphenyl)coumarin (1) and 0.28 g (1.6 mmol) 3nitrophthalonitrile (3) were dissolved in 15 mL anhydrous DMF under argon atmosphere and 0.35 g (2.4 mmol) anhydrous K2CO3 was added to this solution during 2 h. After stirring under argon atmosphere at 550C for 48 h, the reaction mixture was cooled to room temperature. The reaction mixture was poured into cold water and the formed precipitate was filtered, washed with water and then dried. The crude product was purified by column chromatography on silica gel using chloroform as eluent. The yellow compound is soluble in dichloromethane, THF, chloroform, DMF and DMSO. Yield: 0.48 g (77%). Mp.: 187 0C. FT-IR γmax(cm-1): 3079 (ArCH), 2960-2836 (Aliphatic CH), 2225 (-CN), 1712 (C=O lactone), 1571(C=C), 1273 (Ar-OAr). 1H NMR (CDCl3), ppm: Aromatic protons: 7.69 (dd, 7.86 Hz and 8.70 Hz, 1H), 7.62 (d, 8.93 Hz, 1H), 7.60 (dd, 7.73 Hz and 0.93, 1H), 7.38 (dd, 8.19 Hz and 8.23 Hz, 1H), 7.28 (dd, 8.56 Hz and 1.23 Hz, 1H), 7.27 (d, 8.25 Hz, 1H), 7.27 (d, 1.03 Hz, 1H), 7.05 (d, 2.28 Hz, 1H), 7.05 (dd, 6

8.96 Hz and 2.41 Hz, 1H), 6.99 (dd, 8.33 Hz and 2.69 Hz, 1H), lactone proton: 7.83 (s, 1H, CH), aliphatic protons: 3.84 (s, 3H, -OCH3). Anal. Calc. for C24H14N2O4 (394.38): C, 73.09; H, 3.58; N, 7.10 %; Found: C, 72.93; H, 3.48; N, 7.01 %. MS (MALDI-TOF) m/z: 394.441 [M]+. 2.2.3. General procedure for synthesis of phthalocyanines: A mixture of 0.1 g (0.25 mmol) phthalonitrile compound (4 or 5) and metal salt [0.01 g (0.05 mmol) zinc(II) acetate dihydrate, 0.014 g (0.05 mmol),magnesium(II) acetate tetrahydrate, or 0.01g (0.05 mmol) indium(III) acetate] in 2 mL N,N-dimethylaminoethanol (DMAE) was heated to 160-1700C under argon atmosphere for 16 h in a sealed glass tube. After this time, the reaction mixture was cooled to room temperature and precipitated by addition of methanol. The green precipitate was filtered and washed several times with hot methanol, hot ethanol, acetic acid and hot acetonitrile. The crude product was purified by column chromatography on silica gel using chloroform as eluent.

2.2.3.1. 2(3),9(10),16(17),23(24)-Tetrakis[3-(m-methoxyphenyl)-2-oxo-2H-chromen-7yloxy]phthalocyaninato zinc(II) (4a) Yield: 0.026 g (25%). M.p.>300 0C. UV–vis (DMF):  max/nm (log): 350 (4.92), 610 (4.43), 676 (5.02). FT-IR γmax(cm−1): 3045 (Ar-CH), 2932-2830 (aliphatic CH), 1721 (C=O lactone), 1597 (C=C). 1H NMR (CDCl3), ppm: Aromatic protons: 7.84-6.34 (m, 44H), aliphatic protons: 3.76 (s, 12H). Anal. Calc. for C 96H56N8O16Zn (1642,93): C, 70.18; H, 3.44; N, 6.82 %; Found: C, 70.01; H ,3.28; N, 6.61 %. MS (MALDI-TOF) m/z : 1643,605 [M+H] +.

2.2.3.2. 2(3),9(10),16(17),23(24)-Tetrakis[3-(m-methoxyphenyl)-2-oxo-2H-chromen-7yloxy]phthalocyaninato indium(III) acetate (4b) 7

Yield: 0.018 g (16%). M.p.>300 0C. UV–vis (DMF):  max/nm (log): 352 (4.76), 621 (4.15), 690 (4.86). FT-IR γmax(cm−1): 3062 (Ar- CH), 2932-2830 (aliphatic CH), 1721 (C=O lactone), 1597 (C=C). 1H NMR (CDCl3), ppm: Aromatic protons: 7.83–6.42 (m, 44H), In-OCOCH3: 2.83 (s, 3H) and aliphatic protons on the phenyl group: 3.75 (s, 12H).Anal. Calc. for C98H59N8O18In (1751.41): C, 67.21; H, 3.39; N, 6.39 %. Found: C, 67.10; H, 3.27; N, 6.16 %. MS (MALDITOF) m/z : 1752.458 [M+H]+.

2.2.3.3. 2(3),9(10),16(17),23(24)-Tetrakis[3-(m-methoxyphenyl)-2-oxo-2H-chromen-7-yloxy] phthalocyaninato magnesium(II) (4c) Yield: 0.0132 g (13%). M.p. >3000C. UV-vis (DMF): max/nm (log): 351 (4.93), 610 (4.32), 677 (5.07). FT-IR γmax(cm−1): 3062 (Ar- CH), 2932-2830 (aliphatic CH), 1721 (C=O lactone), 1597 (C=C). 1H NMR (CDCl 3), ppm: Aromatic protons: 7.79-6.37 (m, 44H), aliphatic protons: 3.68 (s, 12H). Anal. Calc. for C96H56N8O16Mg (1601.85): C, 71.98; H, 3.52; N, 6.99 %. Found: C, 71.73; H, 3.47; N, 6.81%. MS (MALDI-TOF) m/z: 1601.979 [M]+. 2.2.3.4.

1(4),8(11),15(18),22(25)-Tetrakis[3-(m-methoxyphenyl)-2-oxo-2H-chromen-7-yloxy]

phthalocyaninato zinc(II) (5a) Yield: 0.02 g (20%). M.p.>300 0C. UV–vis (DMF):  max/nm (log): 337 (5.05), 621 (4.58), 690 (5.36). FT-IR γmax(cm−1): 3062 (Ar-CH), 2932-2830 (aliphatic CH), 1721 (C=O lactone), 1577 (C=C). 1H NMR (CDCl3), ppm: Aromatic protons: 7.87-6.35 (m, 44H), aliphatic protons: 3.76 (s, 12H). Anal. Calc. for C96H56N8O16Zn (1642.93): C, 70.18; H, 3.44; N, 6.82%; Found: C 70.02, H 3.37, N 6.74 %. MS (MALDI-TOF) m/z: 1643.605 [M+H]+.

8

2.2.3.5.

1(4),8(11),15(18),22(25)-Tetrakis[3-(m-methoxyphenyl)-2-oxo-2H-chromen-7-yloxy]

phthalocyaninato indium(III) acetate (5b) Yield: 0.019 g (18%). M.p.>300 0C. UV–vis (DMF): max/nm (log): 340 (5.11), 637 (4.55), 705 (5.31). FT-IR γmax(cm−1): 3062 (Ar-CH), 2932-2830 (aliphatic CH), 1721 (C=O lactone), 1577 (C=C). 1H NMR (CDCl3), ppm: Aromatic protons: 7.91–6.44 (m, 44H), In-OCOCH3: 2.77 (s, 3H) and aliphatic protons on the phenyl group: 3.73 (s, 12H). Anal. Calc. for C98H59N8O18In (1751.41): C, 67.21; H, 3.39; N, 6.39 %. Found: C, 67.07; H, 3.11; N, 6.24 %. MS (MALDITOF) m/z : 1752.478 [M+H]+. 2.2.3.6.

1(4),8(11),15(18),22(25)-Tetrakis[3-(m-methoxyphenyl)-2-oxo-2H-chromen-7-yloxy]

phthalocyaninato magnesium(II) (5c) Yield: 0.011 g (11%). M.p. >3000C. UV–vis (DMF):  max/nm (log ): 342 (4.64), 620 (4.11), 689 (4.91). FT-IR γmax(cm−1): 3016 (Ar-CH), 2949-2836 (aliphatic CH), 1718 (C=O lactone), 1608 (C=C). 1H NMR (CDCl3), ppm: Aromatic protons: 7.83-6.39 (m, 44H), aliphatic protons: 3.71 (s, 12H). Anal. Calc. for C96H56N8O16Mg (1601.85): C, 71.98; H, 3.52; N, 6.99 %. Found: C, 71.66; H, 3.37; N, 6.79 %. MS (MALDI-TOF) m/z: 1602.852 [M+H]+. 2.3. Photophysical parameters 2.3.1. Fluorescence quantum yields and lifetimes Fluorescence quantum yields (ΦF) of the studied phthalocyanines were determined by the comparative method using equation 1 [33].

9

(1) where F and FStd are the areas under the fluorescence emission curves of phthalocyanines (4ac and 5a-c) and the standard, respectively. A and AStd are the respective absorbances of the samples and standard at the excitation wavelengths, respectively.

and

are the

refractive indices of solvents used for the sample and standard, respectively. Unsubstituted ZnPc (ΦF = 0.17 in DMF) [34] was employed as the standard. The absorbance of the solutions at the excitation wavelength ranged between 0.04 and 0.05. Natural radiative (0) lifetimes were determined using PhotochemCAD program, which uses the Strickler-Berg equation [35,36]. The fluorescence lifetimes ( F) were evaluated using equation 2.

(2) 2.4. Photochemical parameters 2.4.1. Singlet oxygen quantum yields Singlet oxygen quantum yields ( ) of the studied phthalocyanines were determined in DMF by using the experimental set-up described in the literature [33]. Typically, 2 mL portion of phthalocyanine (4a-c and 5a-c) solutions (concentration= 1x10-5 M) containing the singlet oxygen quencher was irradiated in the Q band region by the photo-irradiation set-up described in literature [33]. 1,3-Diphenylisobenzofuran (DPBF) was used as chemical quencher for singlet oxygen determination in DMF. Singlet oxygen quantum yields (ΦΔ) were performed in air using the relative method with unsubstituted ZnPc (in DMF) as reference. Equation 3 was used for 10

calculations:

(3) where

is the singlet oxygen quantum yield for the standard unsubstituted zinc

phthalocyanine (

= 0.56 in DMF) [34]. R and R Std are the DPBF photobleaching rates in

the presence of the studied phthalocyanines (4a-c and 5a-c) and standards, respectively. I abs and

are the absorbed light by phthalocyanines (4a-c and 5a-c) and standard, respectively.

To avoid chain reactions induced by DPBF in the presence of singlet oxygen [37], the concentration of quencher was lowered to ~3 x 10 -5 M. Solutions of photosensitizers (C=1x10 -5 M) containing DPBF were prepared in the dark and irradiated in the Q band region using the photo-irradiation set-up. DPBF degradation at 417 nm was monitored. The light intensity used for ΦΔ determinations was found to be 7.05x 1015 photons s-1 cm-2. 2.4.2. Photodegradation quantum yields Photodegradation quantum yield (Φ d) determinations were carried out using the experimental set-up described in the literature [33]. Photodegradation quantum yields were determined using equation 4,

(4) where C0 and Ct are phthalocyanine (4a-c and 5a-c) concentrations before and after irradiation respectively, V is the reaction volume, N A is the Avogadro’s constant, S is the irradiated cell area, t is the irradiation time and I abs is the overlap integral of the radiation 11

source light intensity and the absorption of phthalocyanines (4a-c and 5a-c). A light intensity of 2.35x1016 photons s-1 cm-2 was employed for Φ d determinations.

3. Results and discussion 3.1. Synthesis and characterization The general synthetic routes for the synthesis of new phthalonitriles (4 and 5) and their tetraperipherally and non-peripherally substituted Zn(II) (4a and 5a), In(III)(OAc) (4b and 5b) and Mg(II) (4c and 5c) phthalocyanine derivatives were given in Scheme 1. 4-[3-(m-methoxyphenyl)2-oxo-2H-chromen-7-yloxy]phthalonitrile (4) was prepared through base catalyzed nucleophilic aromatic replacement reaction of 7-hydroxy-3-(m-methoxyphenyl)coumarin (1) with 4nitrophthalonitrile (2) in DMF at 650C and 3-[3-(m-methoxyphenyl)-2-oxo-2H-chromen-7yloxy]phthalonitrile

(5)

was

also

prepared

by

the

reaction

of

7-hydroxy-3-(m-

methoxyphenyl)coumarin (1) with 3-nitrophthalonitrile (3) in DMF at 550C. The crude products (4 and 5) were purified by column chromatography on silica gel using CHCl 3 as eluent. The Zn(II) (4a and 5a), In(III)(AcO) (4b and 5b) and Mg(II) (4c and 5c) phthalocyanines were obtained by the reaction of aromatic phthalonitriles (4 and 5) with respective metal salts (Zn(AcO)2.2H2O, In(III)(AcO)3 or Mg(II)(AcO)2.4H2O) in DMAE at 160-1700C under argon atmosphere. After completion of the reaction, the crude products were washed several times with different solvents such as methanol, ethanol and acetonitrile and they were purified by column chromatography on silica gel using CHCl3 as an eluent. The novel compounds were characterized by FT-IR, UV-Vis, 1H NMR and MALDI-TOF mass spectroscopic techniques and elemental analysis. The obtained data were in accordance with the predicted structures. 12

In the FT-IR spectra of phthalonitriles 4 and 5, the -OH stretching peak at 3316 cm-1 for 7hydroxy-3-(m-methoxyphenyl)coumarin group disappeared after reaction of this compound with 4-nitrophthalonitrile (2) or 3-nitrophthalonitrile (3). Furthermore, extra peaks belonging to -CN stretching were observed at 2227 and 2225 cm-1 for 4 and 5, respectively. These peaks disappeared and the color changed to green after conversion into phthalocyanine derivatives (4ac and 5a-c). In the 1H NMR analysis of phthalonitriles 4 and 5 in CDCl3, the proton signals at the four position of coumarin group were appeared at 8.30 ppm for compound 4 and 7.83 ppm for compound 5 as singlet peaks. The aromatic protons were observed between 8.14 and 6.99 ppm and 7.68 and 6.98 ppm, respectively, integrating totally 10 protons for compounds 4 and 5. The aliphatic methyl protons were observed at 3.80 ppm for compound 4 and 3.84 ppm for compound 5 as singlet peaks. The mass spectra of phthalonitrile compounds were obtained by the MALDI-TOF technique and the molecular ion peaks were observed at m/z: 394.406 [M] + for compound 4, 394.441 [M]+ for compound 5. In the FT-IR spectra for phthalocyanines (4a-c and 5a-c), the -CN stretching peaks belonging to the phthalonitrile compounds at around 2220-2230 cm−1 disappeared after formation of the phthalocyanines. Vibration bands were observed at around 3040-3070 cm-1 for aromatic C–H stretching, 2830–2950 cm -1 for aliphatic C–H stretching, 1719-1721 cm-1 for C=O vibration of the ester groups, 1575-1615 cm-1 for aromatic C=C stretching and 1240-1255 cm -1 for ArO-Ar stretching. The 1H NMR spectra of the studied phthalocyanines (4a-c and 5a-c) were recorded in CDCl3 and they showed broad absorptions when compared with that of corresponding phthalonitrile derivatives (4 and 5). In the 1H NMR spectra of phthalocyanines (4a-c and 5a-c), the aromatic protons were observed in the range of 7.84-6.34 ppm for 13

compound 4a, 7.83-6.42 ppm for compound 4b, 7.79-6.37 ppm for compound 4c, 7.87-6.35 ppm for compound 5a, 7.91-6.44 ppm for compound 5b and 7.83-6.39 ppm for compound 5c, respectively, integrating totally 44 protons for each phthalocyanines. The aliphatic protons were observed between 3.68 and 3.76 ppm for all phthalocyanines integrating totally 12 protons for each phthalocyanines (4a-c and 5a-c). The aliphatic protons on the axial acetate groups were observed at 2.83 and 2.77 ppm for compounds 4b and 5b, respectively, integrating 3 protons for each phthalocyanines. In the mass spectra of studied phthalocyanines (4a-c and 5a-c), the presence of molecular ion peaks at m/z = 1643.605 [M] + for 4a, 1752.478 [M+H]+ for 4b, 1601.979 [M] + for 4c, 1643.605 [M]+ for 5a, 1752.478 [M+H]+ for 5b and 1602.852 [M+H]+ for 5c (Figure 1 as examples for compounds 4a and 5a), confirmed the proposed structures. The elemental analyses for all newly synthesized phthalocyanines gave satisfactory results that were close to calculated values. 3.2. Ground state electronic absorption spectra The electronic spectra of the studied Zn(II) (4a and 5a), In(III)(OAc) (4b and 5b) and Mg(II) (4c and 5c) phthalocyanines showed characteristic absorptions in the Q band region at around 676705 nm in DMF (Figure 2). The B bands for these phthalocyanines were observed at around 350 nm. The spectra showed monomeric behavior evidenced by a single (narrow) Q band, which is typical of metallated phthalocyanine complexes in DMF (Figure 2). The red-shifts were observed for studied Zn(II) (4a and 5a), In(III)(OAc) (4b and 5b) and Mg(II) (4c and 5c) phthalocyanines following substitution with coumarin groups. The Q bands of the non-peripheral substituted complexes were also red shifted when compared to the corresponding peripheral substituted complexes in DMF. The red-shifts were 14 nm between 4a and 5a, 15 nm between 4b and 5b, 14

and 12 nm between 4c and 5c. The observed red spectral shifts are typical of phthalocyanines substituted at the non-peripheral positions and have been explained in the literature [38-39]. Extra red shifts were observed for phthalocyanines 4b and 5b, which contains larger indium(III) metal in the cavities of these complexes. The atomic radius of the indium atom is bigger than the cavity of phthalocyanine framework. For this reason, the indium metal is situated out of phthalocyanine plane. The Q bands of the studied indium(III) phthalocyanines (4b and 5b) were red-shifted compared to the other studied phthalocyanines (4a, 4c, 5a and 5c) due to the centrosymmetrical effect of these phthalocyanines (Table 1) [40]. Aggregation is usually depicted as a coplanar association of rings progressing from monomer to dimer and higher order complexes. It is dependent on the concentration, nature of the solvent, nature of the substituents, complexed metal ions and temperature. The aggregation behavior of the phthalocyanine complexes (4a-c and 5a-c) were investigated at different concentrations in DMF (Figure 3, as an example for phthalocyanine 5b). When the concentration increased, the intensity of absorption of the Q band also increased and there observed no new band due to the formation of aggregated species in DMF. Beer–Lambert law was obeyed for all phthalocyanines in the concentrations ranging from 1.2x10-5 to 2x10-6 M. 7-Oxy-3-(m-methoxyphenyl)coumarin substituted Zn(II), In(III)(OAc) and Mg(II) phthalocyanines did not show any aggregation at these concentration ranges in DMF. 3.3. Fluorescence spectra Fluorescence

emission,

absorption

and

excitation

spectra

of

7-oxy-3-(m-

methoxyphenyl)coumarin substituted phthalocyanines were given in Figure 4 (as examples for compounds 4a, 5b and 4c). Fluorescence emission peaks were listed in Table 1. The observed Stokes shifts for studied phthalocyanines were observed between 12 and 14 nm in DMF. The size 15

of the central metals in the phthalocyanine cavity affected the fluorescence properties of the studied phthalocyanines. The studied Mg(II) phthalocyanines (4c and 5c) showed more intense fluorescence emission than the Zn(II) phthalocyanine derivatives (4a and 5a). It could be due to the smaller size of the magnesium atom than zinc in the cavity of the phthalocyanine core. In addition, the studied In(III)(OAc) phthalocyanines (4b and 5b) showed very limited fluorescence emission due to the larger metal size of the indium metal than the other studied metallophthalocyanines (Figure 5). The shape of the excitation spectra was similar to absorption spectra and both were mirror images of the emission spectra for the studied Zn(II) In(III)(OAc) and Mg(II) phthalocyanines. However, in terms of wavelength, the excitation spectra were slightly red-shifted for all complexes when compared to the absorption spectra. It is suggested that different instruments were used for recording of absorption and fluorescence excitation spectra. 3.4. Fluorescence quantum yields and lifetimes The fluorescence quantum yield (ΦF) and lifetime (F) values of 7-oxy-3-(mmethoxyphenyl)coumarin substituted Zn(II), In(III)(OAc) and Mg(II) phthalocyanines (4a-c and 5a-c) were measured in DMF at room temperature and the obtained data were listed in Table 2. These properties were not evaluated for In(III)(OAc) phthalocyanines since these compounds showed very limited fluorescence emission due to the heavy atom effect of larger indium(III) metal in the phthalocyanine cavity. Although the ΦF values of Zn(II) phthalocyanines (4a and 5a) were lower, these values of Mg(II) phthalocyanines (4c and 5c) were higher compared to the unsubstituted zinc(II) phthalocyanine, which is used as reference for ΦF studies. The peripherally substituted Mg(II) phthalocyanine (4c) showed higher fluorescence emission than unsubstituted Mg(II) phthalocyanine. On the other hand, the non-peripherally substituted Mg(II) 16

phthalocyanine (5c) showed lower fluorescence emission than unsubstituted Mg(II) phthalocyanine. The 7-oxy-3-(m-methoxyphenyl)coumarin substituted Mg(II) phthalocyanines (4c and 5c) showed higher ΦF values than the Zn(II) phthalocyanine counterparts (4a and 5a). It could be due to the smaller atomic radius of the magnesium metal than that of the zinc metal in the phthalocyanine cavity that encourages fluorescence as opposed to intersystem crossing to populate the triplet state. ΦF values were also compared to the positions of the substituents on the phthalocyanine core. The substitution of the 7-oxy-3-(m-methoxyphenyl)coumarin groups at the peripheral positions on the phthalocyanine framework resulted higher ΦF values than the substitution of this group at the non-peripheral position suggesting that less quenching occurred on the excited singlet state by peripheral substitution compared to non-peripheral substitution. The natural radiative lifetime (0), fluorescence lifetime (F) and the rate constants for fluorescence (kF) values were also calculated and the obtained data were listed in Table 2. The fluorescence lifetime (F) values were calculated by equation 2 using natural radiative lifetime (0) values. 3.5. Singlet oxygen quantum yields An efficient photosensitizer must be generating singlet oxygen very effectively to be used in the photodynamic therapy of cancer. Energy transfer between the triplet state of photosensitizer and ground state molecular oxygen leads to the production of singlet oxygen. Many factors may be responsible for the magnitude of the determined quantum yield of singlet oxygen including: triplet excited state energy, ability of substituents and solvents to quench the singlet oxygen, the triplet excited state lifetime and the efficiency of the energy transfer between the triplet excited state and the ground state of oxygen. The values were determined in DMF using a chemical 17

method and 1,3-diphenylisobenzofuran (DPBF) was used as a singlet oxygen quencher. The disappearance of DPBF absorbance at 417 nm was monitored using UV–Vis spectrophotometer. There was no change in the Q band intensity during singlet oxygen determinations (Figure 6 as an example for phthalocyanine 5b), confirming that complexes were not degraded during singlet oxygen studies. The obtained  values for 7-oxy-3-(m-methoxyphenyl)coumarin substituted Zn(II), In(III)(AcO) and Mg(II) phthalocyanines in DMF were given in Table 2. Although the studied In(III)(AcO) phthalocyanines showed higher  values, the Mg(II) phthalocyanines showed lower  values compared to the unsubstituted Zn(II) phthalocyanine. This huge difference among these phthalocyanines’  values could be attributed to the difference sizes of the central metals in the phthalocyanine cavity. Larger indium metal in the cavity of compounds 4b and 5b encourage the intersystem crossing between singlet state and triplet state of the molecules and resulted higher  values compared to the smaller magnesium metal in the cavity of phthalocyanines 4c and 5c. The studied Zn(II) phthalocyanines showed average values between the two other groups studied: Mg(II) and In(III)(AcO) phthalocyanines. As a result, the order of the values according to the metal radii is In(III)Zn(II)Mg(II) and the radius size of the used metals affected the generation of the singlet oxygen properties of the studied phthalocyanines. The values of the studied phthalocyanines also showed differences according to the position of substituents. The substitution of the 7-oxy-3-(m-methoxyphenyl)coumarin groups at the non-peripheral position of the phthalocyanine core generated more singlet oxygen than the substitution of these groups at the peripheral position. It could be due to the longer light absorption of non-peripheral substituted phthalocyanines compared to the peripheral counterparts. The obtained values for the studied phthalocyanines changed from 0.29 to 0.82. Therefore, these phthalocyanines, especially In(III)(AcO) phthalocyanine derivatives, may be 18

potential candidates as photosensitizers in applications requiring singlet oxygen such as PDT. 3.6. Photodegradation studies Degradation of molecules under light irradiation is named as photodegradation and quantified as photodegradation quantum yield (d). The determination of this value is especially important for those molecules intended for use as photocatalytic reactions. The photodegradation quantum yields of 7-oxy-3-(m-methoxyphenyl)coumarin substituted phthalocyanines (4a-c and 5a-c) were studied in DMF by monitoring a decrease in the Q band intensities of these compounds under light irradiation (light intensity 2.35x1016 photons s-1 cm-2). All studied 7-oxy3-(m-methoxyphenyl)coumarin substituted phthalocyanines showed photodegradation instead of phototransformation under light illumination because only a decrease was observed at the intensity of absorption bands (Figure 7 as an example for compound 5b). While the Φd values of 7-oxy-3-(m-methoxyphenyl)coumarin substituted Zn(II) and In(III)(OAc) phthalocyanines were higher, these values were lower for 7-oxy-3-(m-methoxyphenyl)coumarin substituted Mg(II) phthalocyanines when compared to the corresponding unsubstituted counterparts. The nonperipherally substituted Zn(II), In(III) and Mg(II) phthalocyanines (5a, 5b and 5c) were less stable to compared to the peripherally substituted analogues (4a, 4b and 4c). Thus the substitution of phthalocyanine framework with 7-oxy-3-(m-methoxyphenyl)coumarin group on the non-peripheral position seems to decrease the stability of the Zn(II) and In(III)(OAc) phthalocyanines in DMF. On the other hand, the substitution of phthalocyanine with 7-oxy-3-(mmethoxyphenyl)coumarin group seems to increase the stability of the Mg(II) phthalocyanine complexes in DMF.

19

4. Conclusions In

conclusion,

new

tetra-substituted

zinc(II),

indium(III)acetate

and

magnesium(II)

phthalocyanines bearing 7-oxy-3-(m-methoxyphenyl)coumarin groups at the peripheral (4a, 4b and 4c) and non-peripheral (5a, 5b and 5c) positions were prepared and characterized in this study. All the studied phthalocyanines showed excellent solubility in common organic solvents such as dichloromethane, chloroform, THF, DMF and DMSO. The photophysical and photochemical properties of these phthalocyanines were also described in DMF for comparison of the effects of the variety of the central metals (Zn, In or Mg) in the cavity and the position (peripheral or non-peripheral) of the substituents on the framework. The ΦF values of the studied phthalocyanines were found mainly related to the size of the central metals in the phthalocyanine cavity. Mg(II) phthalocyanines (4c and 5c) showed higher fluorescence behavior due to the small size of the magnesium atom whereas In(III)(AcO) phthalocyanines (4b and 5b) showed lower fluorescence behavior due to the larger size of the indium atom. The singlet oxygen quantum yield values, which give indication of the potential of the complexes as photosensitizers in applications where singlet oxygen is required (such as Type II mechanism), ranged from 0.29 to 0.82. At the same time, all non-peripherally substituted phthalocyanines showed higher values compared to peripheral position, which may be due to the absorption of light at a longer wavelength for non-peripheral substitution than compared to peripheral substitution. While the stability of the Zn(II) and In(III)(OAc) phthalocyanine complexes decreased, the stability of the magnesium (II) phthalocyanines increased by the substitution of phthalocyanine framework with 7-oxy-3-(m-methoxyphenyl)coumarin in DMF. As a result, these newly synthesized phthalocyanines

especially In(III)(AcO)

derivatives 20

showed

good

photophysical

and

photochemical properties and these compounds can be potential as Type II photosensitizers in photodynamic therapy applications.

Acknowledgements We are thankful to the Research Foundation of Marmara University, Commission of Scientific Research Project (BAPKO) [Grant Number: FEN-C-YLP-090512-0169].

21

References [1] R. O’Kennedy, Coumarins: Biology, Applications and Mode of Action, in: R.D. Thornes (Ed.), Wiley, Chichester, 1997. [2] T.Z. Yu, P. Zhang, Y.L. Zhao, H. Zhang, J. Meng, D.W. Fan, Spectrochim. Acta A: Mol. Biomol. Spectrosc. 73 (2009) 168-173. [3] A. E. Nkengfack, A. W. Kamden, A.G. Azebaze, Z.T. Fomum, M. Meyer, B. Bodo, F. Van Herden, J. Nat. Prod. 63 (2000) 855–856. [4] D. Olmedo, R. Sancho, L.M. Bedoya, J.L. López-Pérez, E. del Olmo, E. Muñoz, J. Alcami, M.P. Gupta, A. San Feliciano, Molecules 17 (2012) 9245–9257. [5] K.V. Sashidhara, A. Kumar, M. Chatterjee, K.B. Rao, S. Singh, A.K. Verma, G. Palit, Bioorg. Med. Chem. Lett. 21 (2011) 1937–1941. [6] T. Tunali, A. Yarat, M. Bulut, N. Emekli, Br. J. Haematol. 126 (2004) 226–230. [7] E. Quezada, G. Delogu, C. Picciau, L. Santana, G. Podda, F. Borges, V. Garcia-Morales, D. Vina, F. Orallo, Molecules 15 (2010) 270-279. [8] L.M. Kabeya, A.A. de Marchi, A. Kanashiro, N.P. Lopes, C.H.T.P. da Silva, M.T. Pupo, Y.M. Lucisano-Valim, Bioorg. Med. Chem. 15 (2007) 1516–1524. [9] M. Roussaki, C.A. Kontogiorgis, D. Hadjipavlou-Litina, S. Hamilakis, A. Detsi, Bioorg. Med. Chem. Lett. 20 (2010) 3889–3892. [10] M. J. Matos, D. Viña, E. Quezada, C. Picciau, G. Delogu, F. Orallo, L. Santana, E. Uriarte, 22

Bioorg. Med. Chem. Lett. 19 (2009) 3268–3270. [11] N.B. McKeown, Phthalocyanine Materials Synthesis: Structure and Function, Cambridge University Press, 1998. [12]

K. Kadish, K.M. Smith, R. Guilard (Eds.), The Porphyrin Handbook, vols. 15–20, Academic Press, Boston, 2003.

[13] B.A. Bench, A. Beveridge, W.M. Sharman, G.J. Diebold, J.E. van Lier, S.M. Gorun, Angew. Chem. Int. Ed. 41 (2002) 747-750. [14] J. Usuda, S.M. Chiu, E.S. Murphy, M. Lam, A.L. Nieminen, N.L. Oleinick, J. Biol. Chem. 278 (2003) 2021-2029. [15] I. Scalise, E.N. Durantini, Bioorg. Med. Chem. 13 (2005) 3037-3045. [16] J.V. Bakboord, M.J. Cook, E. Hamuryudan, J. Porphyrins Phthalocyanines 4 (2000) 510517. [17] R.D. George, A.W. Snow, J.S. Shirk, W.R.J. Barger, J. Porphyrins Phthalocyanines 2 (1998) 1-7. [18] M.J. Cook, J. McMurdo, D.A. Miles, R.H. Poynter, J.M. Simmons, S.D. Haslam, R.M. Richardson, K. Welford, J. Mater. Chem. 4 (1994) 1205-1213. [19] H. Ali, J.E. van Lier, Chem. Rev. 99 (1999) 2379-2450. [20] D. Dini, M. Hanack, The Porphyrin Handbook, in: K.M. Kadish, K.M. Smith, R. Guilard (Eds.), vol. 17, Academic Press, USA, 2003. [21] Y. Chen, M. Hanack, Y. Araki, O. Ito, Chem. Soc. Rev. 34 (2005) 517-529. [22] H. Bartagnolli, W.J. Blau, Y. Chen, D. Dini, S.M. O’Flaherty, M. Hanack, V. Kishnan, J. Mater. Chem. 15 (2005) 683-689. [23] M. Hanack, T. Schneider, M. Barthel, J.S. Shirk, S.R. Flom, R.G.S. Pong, Coord. Chem. 23

Rev. 219–221 (2001) 235-258. [24] D. Dini, M. Barthe, M. Hanack, Eur. J. Org. Chem. 20 (2001) 3759-3769. [25] M. Calvete, G.Y. Yang, M. Hanack, Synth. Met. 141 (2004) 231-243. [26] M. Pişkin, M. Durmuş, M. Bulut, J. Photochem. Photobiol. A: Chem. 223 (2011) 37– 49. [27] Maria João Matos, Fernanda Rodríguez-Enríquez, Santiago Vilar, Lourdes Santana, Eugenio Uriarte, George Hripcsak, Martín Estrada, María Isabel Rodríguez-Franco, Dolores Viña,Bioorganic & Medicinal Chemistry Letters, 25(2015)642-648. [28] U. Michelsen, H. Kliesch, G. Schnurpfeil, A.K. Sobbi, D. Wöhrle, Photochem. Photobiol. 64 (1996) 694-701. [29] D.D. Perrin, W.L.F. Armarego, Purification of Laboratory Chemicals, Second Ed., Pergamon Press, Oxford, 1989. [30] S. Kirkiacharian, F. Bouchoux, E. Cerede, M. Resche-Rigon, A.T. Lormier, Annales Pharmaceutiques Francaises 61 (2003) 51 - 56. [31] R.D. George, A.W. Snow, J. Heterocyclic Chem. 32 (1995) 495–498. [32] J.G. Young, W. Onyebuagu, J. Org. Chem. 55 (1990) 2155–2159. [33] I. Seotsanyana-Mokhosi, N. Kuznetsova, T. Nyokong, J. Photochem. Photobiol. A: Chem. 140 (2001) 215–222. [34] Y. Zorlu, F. Dumoulin, M. Durmuş, V. Ahsen, Tetrahedron 66 (2010) 3248-3258. [35] S.J. Strickler, R.A. Berg, J. Chem. Phys. 37 (1962) 814-822. [36] H. Du, R.A. Fuh, J. Li, A. Corkan, J.S. Lindsey, Photochem. Photobiol. 68 (1998) 141–142. 24

[37] W. Spiller, H. Kliesch, D. Wöhrle, S. Hackbarth, B. Roder, G. Schnurpfeil, J. Porphyrins. Phthalocyanines 2 (1998) 145-158. [38] A.B. Anderson, T.L. Gordon, M.E. Kenney, J. Am. Chem. Soc. 107 (1985) 192-195. [39] H. Konami, M. Hatano, A. Tajiri, Chem. Phys. Lett. 166 (1990) 605-608. [40] T. Nyokong, Struct. Bond. 135 (2010) 45-88. [41] V. Chauke, M. Durmuş, T. Nyokong, J. Photochem. Photobiol. A 192 (2007) 179-187.

25

Table 1. Absorption, excitation and emission spectral data for unsubstituted and substituted Zn(II), In(III(OAc)) and Mg(II) phthalocyanines in DMF. Q band Compound

a

max, (nm)

log 

Excitation

Emission

Stokes shift

Ex, (nm)

Em, (nm)

(nm)

4a

676

5.02

682

688

12

5a

690

5.36

694

703

13

4b

690

4.86

692

704

14

5b

705

5.31

713

719

14

4c

677

5.07

681

690

13

5c

689

4.91

694

700

12

ZnPca

670

5.37

670

676

6

ClInPcb

681

5.04

681

696

15

MgPc

669

5.03

675

681

12

Data from ref. [34].

b

Data from ref. [41].

26

Table 2. Photophysical and photochemical parameters of unsubstituted and substituted Zn(II), In(III)(OAc) and Mg(II) phthalocyanines in DMF. kF (s-1)

d

(x107)

(x 10-5)

a

Compound

F

F (ns)

0 (ns)



4a

0.10

1.07

11.43

8.75

50.4

0.52

5a

0.08

0.54

6.59

15.16

80.0

0.68

4b

-

-

-

-

27.8

0.69

5b

-

-

-

-

64.2

0.82

4c

0.27

3.31

12.28

8.14

12.1

0.29

5c

0.21

4.07

19.40

5.15

25.6

0.31

ZnPca

0.17

1.03

6.05

16.53

2.3

0.56

ClInPcb

0.017

0.11

12.89

15.5

1.0

0.70

MgPc

0.23

4.58

19.94

5.02

32.7

0.28

a

Data from Ref. [34].

b

Data from Ref. [41].

27

FIGURE CAPTIONS Scheme 1. Synthesis of tetra-(7-oxy-3-(m-methoxyphenyl)coumarin)-substituted zinc(II), indium(III)acetate and magnesium(II) phthalocyanine complexes (4a-c, 5a-c). i) DMF, K2CO3, 50-700C; ii) DMAE, metal salts, reflux. Figure 1. The MALDI-TOF spectra of (a) compound 4a and (b) compound 5a. Figure 2. UV-Vis absorption spectra of peripheral (A) and non-peripheral (B) 7-oxy-3-(mmethoxyphenyl)coumarin-substituted (a) zinc(II), (b) indium(III) acetate and (c) magnesium(II) phthalocyanines in DMF. Concentration: 1.0x10-5 M. Figure 3. UV-Vis absorption spectral changes of 5b in DMF at different concentrations. (Inset: Plot of absorbance versus concentration). Figure 4. Electronic absorption, excitation and emission spectra of 4a (A), 5b (B) and 4c (C) in DMF. Excitation wavelengths: 646 nm for 4a, 669 nm for 5b and 645 nm for 4c. Emission spectra of 4a Figure 5. Fluorescence emission spectra of 4a, 4b and 4c in DMF. Concentration: 5.0x10-6. Excitation wavelengths: 646 nm for 4a, 655 nm for 4b and 645 nm for 4c. Figure 6. UV-Vis spectra changes during the determination of singlet oxygen quantum yield. This determination was for compound 5b in DMF at a concentration of 1 x10-5 M. (Inset: Plot of DPBF absorbance versus time). Figure 7. UV-Vis spectra changes during the photodegradation studies of compound 5b in DMF showing the disappearance of the Q-band at one minute intervals. (Inset: Plot of absorbance versus time).

28

OR

N O

O

OH O2N

CN

H3CO

RO

i

CN

N

RO CN

CN

N

N

N

M

N

N

N

O R

4

2

1

ii

OR

4a-c

OR NO2 O

O

OH

OR CN

CN

i

ii

OR

N

H3CO CN

N

CN

N

3

1

N M N

N N N

OR

5 RO

5a-c O

R=

O

M: Zn(II) (4a and 5a) In(III)OAc (4b and 5b) Mg(II) (4c and 5c)

H3CO

Scheme 1

29

(a)

(b)

Figure 1

30

2.5

(a)

Absorbance

2

A

1.5

B

1 0.5 0 300

400

500

600

700

800

Wavelength (nm)

Absorbance

2.5

(b)

2

A B

1.5 1 0.5 0 300

400

500

600

700

800

Wavelength (nm)

Absorbance

1.2

(c)

1

A B

0.8 0.6 0.4 0.2 0 300

400

500

600

Wavelength (nm) Figure 2 31

700

800

3

2.5

1,20 E-05

y = 204445x 1.5R² = 0.9986

Absorbance

2.5

0.5

Absorbance

2

-0.5 0.00E+005.00E-061.00E-05

1.5

Concentration (M)

1

0.5

0 300

500 Wavelength 700 (nm) Figure 3

32

0.2

(A)

300

Intensity

0.16

Emission

250

Excitation

200

0.12

Absorbance

150

0.08

100

Absorption

350

0.04

50 0

0 500

550

600

650

700

750

800

Wavelength (nm) 80

0.4

(B) 0.3 Emission 40

0.2

20

0.1

0

Absorption

Intensity

60

0 500

550

600

650

700

750

800

Wavelength (nm)

0.25

(C)

Intensity

800 600

Emission

0.2

Excitation

0.15

400

0.1

200

0.05

0

0 500

600

700

Wavelength (nm) Figure 4

33

800

Absorption

1000

1000 800

Intensity

4 a

600 400 200 0 655

675

695 715 Absorbance Figure 5

34

735

755

DBPF…

1.6

1.6 1.2 0.8 0.4 0

1.4 1.2

y = -0.0353x + 1.466 R² = 0.9965

0

10 (sec) 20 Time

Absorbance

1

30

0.8

0 sec 5 sec

0.6 0.4 0.2 0 300

400

500 600 (nm) 700 Wavelength

Figure 6

35

800

2.5

2

2

1

Absorbance

0

Absorbance

3

0

1.5

y = -0.0029x + 2.0518 R² = 0.9973

100 200 300(sec) 400 500 Time

0 sec 60 sec 120 sec

1

0.5 0 300

400

500 600 (nm) 700 Wavelength

800

Figure 7

Highlights 1. Synthesis and characterization of Tetra peripherally and non-peripherally 7-oxy-3-(mmethoxyphenyl)coumarin-substituted zinc(II), indium(III)acetate and magnesium(II) phthalocyanine complexes. 2. Investigation of photophysical and photochemical properties of the compounds in DMF solvent. 3. The effects of the variety of metals (Zn, In or Mg) in the cavity and the position (peripheral or non-peripheral) of substituents on photophysical and photochemical parameters of these complexes.

36