32
W. Xi et al. / Dyes and Pigments 122 (2015) 31e39
Scheme 1. Synthetic route for dye 1.
2
. Experimental
was continuously milled for another 30 min. After completion of
the reaction (monitored by thin layer chromatography (TLC)), the
mixture was dispersed in dichloromethane, and then washed by
water for three times. Concentrated the solution to get yellow solid
1 (0.57 g, yield 79.4%). Crystals were prepared in the mixed solvent.
Crystals of T1 and C2 were obtained in dichloromethane/methanol
and crystals of T2 and C1 were obtained in dichloromethane/
ethanol, respectively. Different crystals were separated according to
2
.1. Materials and instruments
All solvents and starting materials were obtained commercially
and used without purification. Double distilled water was used
throughout all experiments. The intermediates a and b were syn-
thesized efficiently according to the literature [14,15]. IR spectra
were recorded with an FT-IR spectrometer (KBr discs) in the 4000-
their shape.
ꢀ1
1
4
00 cm region. NMR spectra were recorded on a 400 MHz NMR
T1: H NMR (400 MHz, DMSO-d
6
):
d
8.28 (t, J ¼ 7.2, 4H), 7.96 (dd,
instrument using DMSO-d as the solvent. Chemical shifts are re-
6
J ¼ 17.4, 8.4, 4H), 7.75-7.53 (m, 4H), 7.46 (d, J ¼ 3.8, 4H), 7.32 (dd,
13
ported in parts per million relative to internal TMS (0 ppm), and
coupling constants are reported in hertz. Splitting patterns are
described as singlet (s), doublet (d), triplet (t), quartet (q), or
multiplet (m). Mass spectra were obtained on LTQ Orbitrap XL mass
spectrometer or autoflex-speed MALDI-TOF/TOF mass spectrom-
eter. Thermal transitions were studied by differential scanning
calorimetry (DSC-2000) and thermogravimetric analysis (TGA-
J ¼ 7.8, 3.8, 2H). C NMR (100 MHz, DMSO-d
6
): d 146.28, 143.91,
139.89, 136.90, 135.47, 132.32, 128.73, 127.43, 127.16, 126.86, 126.31,
ꢀ
1
124.08, 122.83, 120.55, 120.21, 109.72. IR
n (cm ): 3043 (w), 2920
(w), 2511 (w), 1795 (w), 1587 (vs), 1512 (vs), 1450 (vs), 1334 (vs),
1232 (s), 1170 (m), 1107 (s), 966 (m), 840 (m), 748 (s), 622 (w), 534
(m). Anal. Calcd for C26
H
18
N
2
O
2
(%): C, 79.98; H, 4.65; N, 7.17. Found:
þ
C, 79.12; H, 4.65; N, 7.05. HRMS (ESI-MS) m/z: calcd for [MþH] ,
ꢁ
ꢀ1
2
000) at a heating rated of 10 and 20 C min under nitrogen,
390.43; found, 390.14.
1
respectively. One-photon absorption spectra were recorded on a
UV-265 spectrophotometer. One-photon-excited fluorescence
spectra were measured using a Hitachi F-7000 fluorescence spec-
trophotometer. SEM images were obtained using a Hitachi S-4800
scanning electron microscope. Dynamic light scattering (DLS)
measurements were conducted on a Delsa PN A54412AB Nano
Submicron Grain Particle Size Analyzer. Time resolved fluorescence
measurements were performed on a HORIBA FluoroMax-4P fluo-
rescence spectrofluorometer. Single-crystal X-ray diffraction mea-
surements were performed on Bruker SMART CCD area detector
T2: H NMR (400 MHz, DMSO-d
6
):
d
8.28 (t, J ¼ 7.2, 4H), 7.96 (dd,
J ¼ 17.4, 8.4, 4H), 7.75-7.53 (m, 4H), 7.46 (d, J ¼ 3.8, 4H), 7.32 (dd,
13
J ¼ 7.8, 3.8, 2H). C NMR (100 MHz, DMSO-d
6
): d 146.28, 143.91,
139.89, 136.90, 135.47, 132.32, 128.73, 127.43, 127.16, 126.86, 126.31,
ꢀ
1
124.08, 122.83, 120.55, 120.21, 109.72. IR
n (cm ): 3064 (w), 2922
(w), 1795 (w), 1589 (vs), 1514 (vs),1450 (vs),1340 (vs),1228 (s), 1176
(m), 1107 (m), 956 (m), 846 (s), 754 (vs), 684 (m), 621 (m), 534 (s),
426 (w). Anal. Calcd for C26H N O (%): C, 79.98; H, 4.65; N, 7.17.
18 2 2
Found: C, 79.61; H, 4.51; N, 7.12. HRMS (ESI-MS) m/z: calcd for
þ
[MþH] , 390.43; found, 390.14.
1
using graphite-monochromatized Mo K
at room temperature. Intensity data were collected in the variable
-scan mode. The structures were solved by direct methods and
a
radiation (
l
¼ 0.71069 Å)
C1: H NMR (400 MHz, DMSO-d
6
):
d
8.23 (dd, J ¼ 14.6, 7.5, 4H),
7.66e7.39 (m, 10H), 7.30 (t, J ¼ 7.0, 2H), 6.94 (dd, J ¼ 54.6, 12.5, 2H).
13
u
C NMR (100 MHz, DMSO-d
6
): d 149.19, 143.86, 139.82, 136.24,
difference Fourier syntheses. The non-hydrogen atoms were
refined anisotropically and hydrogen atoms were introduced
geometrically. Calculations were performed with SHELXTL-97
program package. Crystallographic data for the structure reported
in this paper have been deposited with the Cambridge Crystallo-
graphic Data Centre as supplementary publication no. 1024319
134.97, 132.51, 130.33, 129.77, 128.72, 126.59, 126.25, 123.77, 122.76,
ꢀ1
120.50, 120.15, 109.69. IR
n (cm ): 3055 (w), 3006 (w), 1919 (w),
1793 (w), 1593 (vs), 1512 (vs), 1452 (vs), 1430 (vs), 1230 (vs), 1182
(m), 1105 (m), 1014 (m), 891 (m), 854 (s), 750 (vs), 624 (m), 493 (w),
428 (w). Anal. Calcd for C26
H
18
N
2
O
2
(%): C, 79.98; H, 4.65; N, 7.17.
þ
Found: C, 79.56; H, 4.60; N, 6.99. MALDI-TOF m/z: calcd for [MþH] ,
(T1), 1025558 (T2), 1024330 (C1), 990815 (C2).
390.43; found, 390.25.
1
C2: H NMR (400 MHz, DMSO-d
6
):
d
8.23 (dd, J ¼ 14.6, 7.5, 4H),
2.2. Synthesis and crystallization
7.66e7.39 (m, 10H), 7.30 (t, J ¼ 7.0, 2H), 6.94 (dd, J ¼ 54.6, 12.5, 2H).
13
C NMR (100 MHz, DMSO-d
6
): d 149.19, 143.86, 139.82, 136.24,
t-BuOK (0.6 g, 5.35 mmol) was placed into a dry mortar and well
milled into powder, then a (0.5 g, 1.84 mmol) and b (1.0 g,
.09 mmol) were added and mixed. The mixture was milled
vigorously for about 20 min under the infrared lamp. The mixture
became sticky, and then dichloromethane was added. The mixture
134.97, 132.51, 130.33, 129.77, 128.72, 126.59, 126.25, 123.77, 122.76,
120.50, 120.15, 109.69. IR n (cm ): 3060 (w), 3020 (w), 2927 (w),
2833 (w), 1922 (w), 1595 (vs), 1512 (vs), 1452 (vs), 1338 (vs), 1228
(vs), 1180 (s), 1107 (s), 1016 (m), 892.99 (s), 854 (s), 752 (vs), 624 (s),
18 2 2
563 (m), 489 (m), 445 (m). Anal. Calcd for C26H N O (%): C, 79.98;
ꢀ
1
2