J. Ren et al. / Dyes and Pigments 91 (2011) 442e445
443
1.2
_ _
Free, Cl , Br , I
_
_ _
AcO , ClO4 , HSO4
_
O
O
O
O
N
O
O
N
O
1.0
0.8
0.6
0.4
0.2
0.0
n-C4H9NH2
CH3ONa/CH3OH
CuSO4
_
F
Br
Br
OCH3
1
3
2
O
N
O
O
N
O
TBS-Cl
imidizole
HI
H2O
300
350
400
450
500
550
600
Wavelengthen /nm
O Si
TBS-NA
Fig. 1. UVeVis absorption changes of compound 1(1 ꢂ 10ꢀ4 mol/L) upon addition of
OH
tetrabutylammonium salts of Fꢀ, Clꢀ, Brꢀ, Iꢀ, HSOꢀ4 , ClO4ꢀ and AcOꢀ (10 equiv) in CH3CN.
4
Scheme 1. The synthetic route of TBS-NA.
2.2.3. Synthesis of 4-hydroxy-N-butyl-1,8-naphthalimide 4
A mixture of compound 3 (4.0 g, 14.1 mmol) and 100 mL
concentrated HI (57%) was refluxed for 3 h. After cooling and filtra-
2. Materials and methods
2.1. Experimental
l
tion, yellow needles of compound 4 were obtained in 82% yield. H
NMR (CDC13):
d
¼ 0.97 (t, J ¼ 7.2 Hz, 3H, NeCH2CH2CH2CH3),1.45 (m,
2H, NeCH2CH2CH2CH3), 1.72 (m, 2H, NeCH2CH2CH2CH3), 4.16(t,
J ¼ 7.8 Hz, 2H, NeCH2CH2CH2CH3), 5.61(s,1H, -OH), 7.12 (d, J ¼ 8.4 Hz,
lH), 7.67 (t, J ¼ 7.8 Hz, 1H), 8.43 (d, J ¼ 8.4 Hz, lH), 8.47 (d, J ¼ 8.4 Hz,
lH), 8.57 (d, J ¼ 7.2 Hz, 1H).
2.1.1. General
Unless otherwise noted, all chemicals were of analytical reagent
grade obtained from commercial suppliers and used without
further purification. Chloroform (CHCl3) were refluxed with calcium
hydride and distilled under atmospheric pressure. THF were
refluxed with Na and distilled under atmospheric pressure. TLC
analyses were performed on silica gel plates and column chroma-
tography was conducted over silica gel (mesh 200e300), both of
which were obtained from Qingdao Ocean Chemicals, China. The
UVeVis absorption spectra were measured by Shimadzu UV-2450
spectrophotometer at 25 ꢁC. 1H NMR spectra in CDCl3 were recor-
ded using Varian Unity Invoa-600 MHz spectrometer with chemical
shifts reported as ppm (TMS as the internal standard).
2.2.4. Synthesis of TBS-NA
A mixture of compound 4 (0.540 g, 2.0 mmol), tert-butyldime-
thylsilyl chloride(0.331 g, 2.2 mmol), imidazole (0.163 g, 2.4 mmmol)
in 10 mL dry CHCl3 were stirred overnight at room temperature.
At the end of the reaction, the solvent was removed in vacuum.
After purification by column chromatography (200e300 mesh silica
gel, 20:1 chloroform/acetone), the desired product was obtained
as off-white solid in 79% yield. lH NMR (CDC13):
d
¼ 0.35(s,
6H, eCH3 ꢂ 2), 1.0(t, J ¼ 9.6 Hz, 3H, NeCH2CH2CH2CH3), 1.08(s,
9H, e(CH3)3), 1.42 (m, 2H, NeCH2CH2CH2CH3), 1.68 (m,2H,
NeCH2CH2CH2CH3), 4.14(t, J ¼ 7.8 Hz, 2H, NeCH2CH2CH2CH3), 7.02(d,
J ¼ 8.4 Hz, lH), 7.68(t, J ¼ 7.8 Hz, 1H), 8.46(d, J ¼ 8.4 Hz, lH), 8.47(d,
J ¼ 8.4 Hz, lH), 8.57 (d, J ¼ 7.2 Hz, 1H).
2.2. Synthesis
2.2.1. Synthesis of 4-bromo-N-butyl-1,8-naphthalic anhydride 2
A mixture of compound 1(5 g, 18 mmol), 1-Aminobutane (1.7 g,
23.3 mmol) in 40 mL acetic acid was stirred under reflux in
a nitrogen atmosphere for 6 h, After the completion of reaction, the
reaction mixture was then poured into a mixture of cracked ice and
water (200 mL) and filtered to get a pale yellow solid. The crude
product was recrystallized from chlorobenzene to give 4.6 g light
gray needles in a yield of 77%. Mp 109e110 ꢁC. The product was
used for next step directly.
3. Result and discussion
The interaction of sensor TBS-NA with the anions was investi-
gated through UVeVis spectra. All the UVeVis behavior of sensor
2.2.2. Synthesis of 4-methoxy-N-butyl-1,8-naphthalimide 3
A mixture of compound 2 (5.4 g, 16.3 mmol), CH3ONa (7.0 g,
130 mmol) and CuSO4$5H2O (0.50 g, 2.0 mmol) in 50 mL CH3OH
were refluxed for 12 h. After the removal of the solvent and washing
of the residue with water (30 mL ꢂ 3). Compound 3 was obtained as
yellow needles in 89% yield. lH NMR (CDC13):
d
¼ 0.95(t, J ¼ 7.2 Hz,
3H, NeCH2CH2CH2CH3), 1. 42 (m, 2H, NeCH2CH2CH2CH3), 1.70 (m,
2H, NeCH2CH2CH2CH3), 4.15(t, 2H, J ¼ 7.8 Hz, NeCH2CH2CH2CH3),
4.11(s, 3H. eOCH3), 7.02(d, J ¼ 8.4 Hz, lH), 7.68(t, J ¼ 7.8 Hz, 1H),
8.54(d, J ¼ 7.8 Hz, 2H), 8.58(d, J ¼ 7.2 Hz, 1H).
Fig. 2. Color changes of the compound 1 (1 ꢂ 10ꢀ4 mol/L) in CH3CN with the addition
of one equiv tetrabutylammonium salts (from left to right: free, Clꢀ, Brꢀ, Iꢀ, HSO4ꢀ
ClOꢀ4 , AcOꢀ, Fꢀ).
,