R.-Z. Ma et al. / Journal of Fluorine Chemistry 137 (2012) 93–98
97
3. Conclusion
CDCl3):
1H, J = 7.6 Hz), 7.89 (m, 3H), 8.17 (t, 1H, J = 8.8 Hz), 8.51 (d, 1H,
J = 8.8 Hz), 8.95 (d, 1H, J = 9.2 Hz); 13C NMR (100 MHz, DMSO-d6):
117.08, 120.34, 120.47, 124.84, 124.92, 126.74, 127.64, 128.06,
128.41, 132.98, 135.64, 140.36, 142.81, 152.83, 156.39; Found: C,
66.83; H, 3.75; N, 5.16; Anal. Calc. for C15H10NOBF2: C, 66.90, H,
3.72; N, 5.20%.
d 7.04 (m, 1H), 7.08 (m, 1H), 7.54 (t, 1H, J = 8.0 Hz), 7.69 (d,
Herein we described the synthesis, structural analysis, spectral
and photophysical property studies of the novel BF2 complexes
bearing 2-(quinolin-2-yl)phenol ligands. The preparation of these
complexes was performed in good to excellent yields under mild
conditions with simple work-up procedures. These dyes displayed
solvent-sensitive absorption and emission features. The electronic
and site effect of substituents played an important role in the
quantum yields of the corresponding complexes. The strong
emission in solutions and in solid state as well as the impressive
large Stokes shifts and the high quantum yields made these
compounds as useful fluorescent materials. Further work on the
development of their potential applications is underway and will
be reported soon.
d
Complex 6d: 71% yield, m.p. > 300 8C; IR (KBr):
1553 (C55C), 1117 (B–F), 929 (B–N) cmꢀ1 1H NMR (400 MHz,
CDCl3): 7.35 (d, 1H, J = 8.8 Hz), 7.91 (t, 1H, J = 7.6 Hz), 8.11 (t, 1H,
n 1615 (C55N),
;
d
J = 7.6 Hz), 8.39 (d, 1H, J = 8.4 Hz), 8.47 (d, 1H, J = 9.2 Hz), 8.71 (d,
1H, J = 8.4 Hz), 8.96 (d, 1H, J = 8.4 Hz), 9.14 (d, 1H, J = 9.2 Hz), 9.26
(s, 1H); 13C NMR (100 MHz, DMSO-d6):
d 118.48, 118.78, 118.95,
124.31, 126.88, 126.94, 127.27, 128.06, 131.29, 139.07, 139.42,
143.56, 155.56, 155.43, 165.96; Found: C, 57.25; H, 2.90; N, 8.86;
Anal. Calc. for C15H9N2O3BF2: C, 57.31; H, 2.86; N, 8.91%.
4. Experimental
Complex 6e: 77% yield, m.p. 294–295 8C; IR (KBr):
n 1607 (C55N),
1555 (C55C), 1089 (B–F), 927 (B–N) cmꢀ1 1H NMR (DMSO-d6):
;
d
4.1. Apparatus and materials
6.99 (d, 1H, J = 8.8 Hz), 7.54 (d, 1H, J = 8.8 Hz), 7.70 (t, 1H,
J = 7.2 Hz), 7.87 (t, 1H, J = 8.4 Hz), 8.10 (t, 2H, J = 8.4 Hz), 8.37 (s,
1H), 8.45 (d, 1H, J = 8.8 Hz), 8.63 (d, 1H, J = 8.8 Hz); 13C NMR
All the reagents used were analytically pure and some
chemicals were further purified by recrystallization or distillation.
(100 MHz, DMSO-d6):
d 110.11, 118.58, 120.17, 120.92, 126.65,
Melting points were determined by
a
X-4 micro melting
126.90, 127.36, 127.99, 130.18, 131.12, 134.52, 138.77, 143.81,
156.07, 159.02; Found: C, 51.67; H, 2.52; N, 4.06; Anal. Calc. for
C15H9NOBF2Br: C, 51.73; H, 2.58; N, 4.02%.
instrument and the thermometer was uncorrected. The 1H NMR
(400 MHz), 13C NMR (100 MHz) and 19F NMR (376 MHz) spectra
were obtained on a Bruker Avance II DMX400 spectrometer using
CDCl3 or DMSO-d6 as the solvent. The 1H NMR and 13C NMR
experiments were carried out using trimethylsilane as the internal
standard and the 19F NMR spectra were recorded using CF3COOH
(ꢀ76.5 ppm) as the external standard. FT-IR spectra were
performed using KBr pellets on a Nicolet Avatar spectrophotome-
ter. The absorption spectra were measured on a Shimadzu UV
2501(PC)S UV–Vis spectrometer and the fluorescence spectra were
acquired on a Perkin-Elmer LS55 spectrophotometer.
Complex 6f: 84% yield, m.p. > 300 8C; IR (KBr):
1543 (C55C), 1095 (B–F), 929 (B–N) cmꢀ1 1H NMR (400 MHz,
CDCl3): 4.00 (s, 6H), 7.31 (d, 1H, J = 9.2 Hz), 7.75 (m, 1H), 8.04 (m,
1H), 8.39 (d, 1H, J = 7.6 Hz), 8.71 (m, 1H), 8.88 (d, 1H, J = 8.8 Hz),
9.14 (m, 1H); 13C NMR (100 MHz, DMSO-d6):
56.08, 56.13,
n 1621 (C55N),
;
d
d
102.67, 107.09, 116.33, 116.48, 120.06, 123.95, 125.20, 129.17,
136.48, 140.84, 142.58, 146.74, 150.49, 154.63, 159.25; Found: C,
54.47; H, 3.51; N, 7.42; Anal. Calc. for C17H13N2O5BF2: C, 54.53; H,
3.47; N, 7.48%.
Complex 6g: 91% yield, m.p. 264–265 8C; IR (KBr):
n 1620 (C55N),
4.2. General procedure for synthesis of complex (6a–i)
1560 (C55C), 1100 (B–F), 920 (B–N) cmꢀ1 1H NMR (DMSO-d6):
;
d
2.39 (s, 3H), 7.11 (d, 1H, J = 8.4 Hz), 7.35 (d, 1H, J = 8.8 Hz), 7.67 (m,
2H), 7.89 (m, 2H), 8.16 (d, 1H, J = 8.8 Hz), 8.49 (d, 1H, J = 8.8 Hz),
At room temperature, triethylamine (2 mmol) was added to the
solution of ligand (1 mmol) in benzene (3 mL), the resulted
mixture was stirred for 20 min and then boron trifluoride etherate
(3 mmol) was added. The mixture was stirred at 50 8C for 1 h and
yellowish solid was gradually precipitated out from the solution.
After cooling to room temperature, the mixture was filtrated and
the solid was washed several times by ether and dried in air. For
microanalysis, the solid was recrystallized in the benzene/hexane
mixture.
8.95 (d, 1H, J = 9.6 Hz); 13C NMR (100 MHz, DMSO-d6):
d 20.84,
117.11, 120.07, 124.71, 124.80, 124.89, 126.45, 127.56, 127.93,
128.37, 129.63, 132.89, 136.84, 142.64, 152.88, 154.33; Found: C,
67.91; H, 4.19; N, 5.01; Anal. Calc. for C16H12NOBF2: C, 67.82; H,
4.24; N, 4.95%.
Complex 6h: 94% yield, m.p. 257–259 8C; IR (KBr):
n 1616 (C55N),
1553 (C55C), 1086 (B–F), 909 (B–N) cmꢀ1 1H NMR (DMSO-d6):
;
d
2.40 (s, 3H), 6.84 (d, 1H, J = 8.0 Hz), 7.00 (s, 1H), 7.64 (t, 1H,
J = 7.6 Hz), 7.76 (d, 1H, J = 8.4 Hz), 7.87 (t, 2H, J = 7.6 Hz), 8.08 (d,
1H, J = 8.8 Hz), 8.43 (d, 1H, J = 8.8 Hz), 9.92 (d, 1H, J = 8.8 Hz); 13C
Complex 6a: 81% yield, m.p. 272–273 8C; IR (KBr):
1556 (C55C), 1110 (B–F), 923 (B–N) cmꢀ1 1H NMR (400 MHz,
CDCl3): 4.02 (s, 3H), 4.14 (s, 3H), 7.00 (m, 1H), 7.03 (m, 1H), 7.18
(m, 1H), 7.46 (t, 1H, J = 7.6 Hz), 7.82 (d, 1H, J = 8.0 Hz), 7.93 (d, 1H,
J = 8.8 Hz), 8.28 (m, 2H); 13C NMR (100 MHz, DMSO-d6):
56.20,
n 1622 (C55N),
;
d
NMR (100 MHz, DMSO-d6): d 21.25, 118.04, 118.17, 119.03,
121.91, 123.15, 127.44, 127.90, 128.03, 129.27, 132.05, 139.01,
143.96, 146.95, 152.32, 155.31; Found: C, 67.86; H, 4.28; N, 4.89;
Anal. Calc. for C16H12NOBF2: C, 67.82; H, 4.24; N, 4.95%.
d
56.62, 104.45, 105.70, 114.90, 116.38, 120.04, 120.29, 124.06,
126.12, 134.48, 137.67, 140.46, 149.81, 150.44, 154.55, 155.41;
Found: C, 61.88; H, 4.21; N, 4.19; Anal. Calc. for C17H14NOBF2: C,
61.98; H, 4.25; N, 4.25%.
Complex 6i: 83% yield, m.p. 243–244 8C; IR (KBr):
n 1617 (C55N),
1557 (C55C), 1109 (B–F), 910 (B–N) cmꢀ1 1H NMR (DMSO-d6):
;
d
3.88 (s, 3H), 6.62 (m, 2H), 7.61 (t, 1H, J = 7.6 Hz), 7.84 (m, 3H), 8.00
(d, 1H, J = 9.2 Hz), 8.37 (d, 1H, J = 9.2 Hz), 8.87 (d, 1H, J = 8.8 Hz);
13C NMR (100 MHz, DMSO-d6):
d 55.69, 102.51, 110.03, 116.69,
124.29, 124.38, 124.47, 126.98, 127.43, 128.08, 128.35, 132.73,
142.19, 152.65, 158.73, 166.06; Found: 64.28; H, 3.96; N, 4.72;
Anal. Calc. for C16H12NO2BF2: C, 64.20; H, 4.01; N, 4.68%.
Complex 6b: 76% yield, m.p. 262–264 8C; IR (KBr):
1586 (C55C), 1099 (B–F), 930 (B–N) cmꢀ1 1H NMR (400 MHz,
CDCl3): 7.04 (m, 1H), 7.19 (m, 1H), 7.54 (t, 1H, J = 7.6 Hz), 7.62 (d,
1H, J = 8.4 Hz), 7.83 (m, 2H), 8.13 (d, 1H, J = 8.8 Hz), 8.46 (d, 1H,
J = 8.8 Hz), 8.96 (m, 1H); 13C NMR (100 MHz, DMSO-d6):
117.31,
n 1614 (C55N),
;
d
d
120.43, 120.67, 124.18, 124.28, 124.38, 125.97, 126.87, 129.24,
129.47, 136.12, 139.66, 142.43, 153.57, 156.44; Found: C, 59.39; H,
3.01; N, 4.56; Anal. Calc. for C15H9NOBF2Cl: C, 59.31; H, 2.96; N,
4.61%.
Acknowledgments
We are grateful for the financial support from the Natural
Science Foundation of Zhejiang Province (Y4100034) and Zhejiang
Provincial Key Innovation Team (2010R50038).
Complex 6c: 86% yield, m.p. 264–265 8C; IR (KBr):
n 1609 (C55N),
1560 (C55C), 1085 (B–F), 922 (B–N) cmꢀ1 1H NMR (400 MHz,
;