F. Yuksel et al. / Dyes and Pigments 90 (2011) 191e200
193
lowered to w3 ꢂ 10ꢁ5 mol dmꢁ3. Solutions of sensitizer containing
DPBF was prepared in the dark and irradiated in the Q band region
using the above set-up. DPBF degradation at 417 nm was moni-
tored. The light intensity was 6.66 ꢂ 1015 photons sꢁ1 cmꢁ2 for FD
determinations.
796, 719. 1H NMR (CDCl3)
d
ppm: 7.59 (m, 2H, CHar), 7.55 (d, H, CHar),
3.06 (t, 2H, SCH2), 1.71 (m, 2H, CH2), 1.46 (m, 2H, CH2), 1.26 (m, 24H,
CH2), 0.88 (t, 3H, CH3). MS (ESI-MS) m/z: Calc. 384; Found: 407
[M þ Na]þ.
2.5.2. 2(3),9(10),16(17),23(24)-tetrakis[(1-mercaptododecyl)
phthalocyaninato] chlorogallium(III) (5a)
2.4.2. Photodegradation quantum yields
Determinations of photodegradation quantum yield (Fd) were
carried out previously described in the literature [37e39]. Fd was
determined using Equation (4),
A mixture of anhydrous gallium(III) chloride (0.27 g, 1.52 mmol),
4-(1-mercaptododecyl) phthalonitrile (3a) (1.00 g, 3.04 mmol), DBU
(0,2 mL) and quinoline (3 mL, doubly distilled over CaH2) was stirred
at 180 ꢀC for 7 h under a nitrogen atmosphere. After cooling, the
solution was dropped into the ethanol. The green solid product that
precipitated was collected by filtration and washed with ethanol.
The crude product was dissolved in CHCl3 and then filtered. After
filtering and concentrating, the green product was purified by
passing through a silica gel column, using THF as the eluting solvent.
Furthermore this product was purified with preparative thin layer
chromatography (silica gel) using CHCl3 as solvent. Yield: 0.42 g,
39%. FT-IR nmax/cmꢁ1 (KBr pellet): 3060 (CHar), 2955e2852 (CH),
1600 (C]C), 1494, 1459, 1395, 1335, 1316, 1254, 1144, 1079, 1040,
ðC0 ꢁ CtÞ$V$NA
Fd
¼
(4)
I
abs$S$t
where C0 and Ct are the Ga(III)Pcs (5a,b and 6a,b) concentrations
before and after irradiation respectively, V, NA, S, t and Iabs are reac-
tion volume, the Avogadro’s constant, irradiated cell area, irradiation
time and the overlap integral of the radiation source light intensity,
respectively. A light intensity of 2.22 ꢂ 1016 photons sꢁ1 cmꢁ2 was
employed for Fd determinations.
920, 815, 743. 1H NMR (CDCl3)
d ppm: 8.78e7.46 (m, 12H, AreCH),
2.4.3. Fluorescence quenching by 1,4-benzoquinone (BQ)
3.41e3.02 (br, 8H, eSCH2), 1.95 (br, 8H, eSCH2CH2), 1.62 (br, 8H,
CH2), 1.50e1.25 (m, 64H, CH2), 0.92 (t, 12H, CH3). Calc for
C80H112ClGaN8S4: %C 67.70, %H 7.95, %N 7.90; Found: %C 67.80, %H
8.05, %N 7.80. MS (MALDI) m/z: Calc. 1419; Found: 1383 [M ꢁ Cl]þ,
1419 [M]þ, 1536 [M ꢁ Cl þ DHB]þ.
Fluorescence quenching experiments on the Ga(III)Pcs (5a,b and
6a,b) were carried out by the addition of different concentrations of
BQ to a fixed concentration of the complexes, and the concentrations
of BQ in the resulting mixtures were 0, 0.008, 0.016, 0.024, 0.032 and
0.040 M. The fluorescence spectra of Ga(III)Pcs (5a,b and 6a) at each
BQ concentration were recorded, and the changes in fluorescence
intensity related to BQ concentration by the SterneVolmer (SeV)
equation [42] was shown in Equation (5):
2.5.3. 2(3),9(10),16(17),23(24)-tetrakis[(1-mercaptohexadecyl)
phthalocyaninato] chlorogallium(III) (5b)
Synthesis and purification was outlined as for 5a except 3b was
employed instead of 3a. The amount of the reagents employed were:
3b (1.00 g, 2.60 mmol), gallium(III) chloride (0.22 g, 1.30 mmol) and
DBU (0.2 mL) in quinoline (3 mL). Yield: 0.33 g, 31%. FT-IR nmax/cmꢁ1
(KBr pellet): 3061 (CHar), 2958e2850 (CH), 1600 (C]C), 1498, 1448,
1397,1335,1312,1255,1148,1075,1036, 915, 815, 744.1H NMR (CDCl3)
I0
I
¼ 1 þ KSV½BQꢃ
(5)
where I0 and I are the fluorescence intensities of fluorophore where
I0 and I are the fluorescence intensities of fluorophore in the absence
and presence of quencher, respectively. [BQ] is the concentration of
the quencher and KSV is the SterneVolmer constant which is the
d
ppm: 8.75e7.50 (m, 12H, AreCH), 3.45e3.06 (br, 8H, eSCH2), 1.97
(br, 8H, eSCH2CH2), 1.69 (br, 8H, CH2), 1.52e1.29 (m, 96H, CH2), 0.93
(t, 12H, CH3). Calc. for C96H144ClGaN8S4: %C 70.15, %H 8.83, %N 6.82;
Found: %C 70.01, %H 9.02, %N 6.70. MS (MALDI) m/z: Calc. 1643;
Found: 1606 [M ꢁ Cl þ 2H]þ, 1760 [M ꢁ Cl þ 2H þ DHB]þ.
product of the bimolecular quenching constant (kq) and the
expressed in Equation (6).
sF and is
KSV ¼ kq$sF
(6)
2.5.4. 1(4),8(11),15(18),22(25)-tetrakis[(1-mercaptododecyl)
phthalocyaninato] chlorogallium(III) (6a)
The ratios of Io/I were calculated and plotted against [BQ]
according to Equation (5), and KSV is determined from the slope.
Synthesis and purification was outlined as for 5a except 4a was
employed instead of 3a. The amount of the reagents employed were:
4a (1.00 g, 3.04 mmol), gallium(III) chloride (0.27 g, 1.52 mmol) and
DBU (0.2 mL) in quinoline (3 mL). Yield: 0.38 g, 35%. FT-IR nmax/cmꢁ1
(KBr pellet): 3060 (CHar), 2960e2850 (CH), 1588 (C]C), 1500, 1465,
1327, 1238, 1190, 1159, 1113, 1080, 909, 794, 740. 1H NMR (CDCl3)
2.5. Syntheses
4-Nitrophthalonitrile [43] (1), 3-nitrophthalonitrile [44] (2), 4-
(1-mercaptododecyl) phthalonitrile [45] (3a), 4-(1-mercapto hex-
adecyl) phthalonitrile [45] (3b), and 3-(1-mercaptododecyl)
phthalonitrile [44] (4a) were synthesized and purified according to
published procedures.
d
ppm: 8.95e7.40 (m, AreCH, 12H), 3.46e2.98 (t, 8H, eSCH2), 2.05
(m, 8H, eSCH2CH2), 1.77 (m, 8H, CH2), 1.63e1.26 (m, 64H, CH2), 0.92
(t, 12H, CH3). Calc. for C80H112ClGaN8S4: %C 67.70, %H 7.95, %N 7.90;
Found: %C 67.82, %H 8.11, %N 7.75. MS (MALDI) m/z: Calc. 1419;
Found: 1383 [M ꢁ Cl]þ, 1536 [M ꢁ Cl þ DHB]þ.
2.5.1. 3-(1-mercaptohexadecyl) phthalonitrile (4b)
The 3-nitrophthalonitrile (2.0 g, 11.6 mmol) was dissolved in
dimethyl sulfoxide (20 mL) under argon atmosphere and hex-
adecane-1-thiol (3.2 g, 12.4 mmol) was added to this solution. After
30 min anhydrous potassium carbonate (2.4 g,17.4 mmol) was added
in portions during 3 h with efficient stirring. The reaction mixture
was stirred under argon atmosphere at ambient temperature. After
24 h, the reaction mixture was added to 100 g ice. The resulting pale
yellow solid was filtered then washed with cold distilled water.
Colorless crystals were obtained by re-crystallization from hot
ethanol. Yield: 3.56 g, 80%. mp: 90 ꢀC. FT-IR nmax/cmꢁ1 (KBr pellet):
3055 (CHar), 2916e2849 (CH), 2230 (C^N), 1566 (C]C), 1469, 1196,
2.5.5. 1(4),8(11),15(18),22(25)-tetrakis[(1-mercaptohexadecyl)
phthalocyaninato] chlorogallium(III) (6b)
Synthesis and purification was outlined as for 5a except 4b was
employed instead of 3a. The amount of the reagents employed were:
4b (1.00 g, 2.60 mmol), gallium(III) chloride (0.22 g, 1.30 mmol) and
DBU (0,2 mL) in quinoline (3 mL). Yield: 0.35 g, 33%. FT-IR nmax/cmꢁ1
(KBr pellet): 3060 (CHar), 2960e2850 (CH), 1590 (C]C), 1468, 1325,
1242, 1190, 1153, 1113, 1082, 908, 794, 740. 1H NMR (CDCl3)
d ppm:
8.97e7.40 (m, 12H, AreCH), 3.47e2.97 (t, 8H, eSCH2), 2.06 (m,
8H, eSCH2CH2), 1.78 (m, 8H, CH2), 1.60e1.29 (m, 96H, CH2), 0.89