New fluorescent chemosensors on the basis of 9-aminomethylanthracene

Full text of DOI:10.1023/B:RUJO.0000010232.50792.88

Russian Journal of Organic Chemistry, Vol. 39, No. 9, 2003, pp. 1364 1366. Translated from Zhurnal Organicheskoi Khimii, Vol. 39, No. 9, 2003,
pp. 1435 1436.
Original Russian Text Copyright
2003 by Tolpygin, Bren’, Dubonosov, Minkin, Rybalkin.
SHORT
COMMUNICATIONS
New Fluorescent Chemosensors
on the Basis of 9-Aminomethylanthracene
I. E. Tolpygin, V. A. Bren’, A. D. Dubonosov, V. I. Minkin, and V. P. Rybalkin
Research Institute of Physical and Organic Chemistry, Rostov State University,
pr. Stachki 194/2, Rostov-on-Don, 344090 Russia
e-mail: dubon@ipoc.rsu.ru
Received April 9, 2003
Fluorescent chemosensors whose action is based on
the PET (photoinduced electron transfer) effect are
widely used in the determination of various substances
in the environment [1, 2]. 9-Aminomethylanthracene
derivatives could give rise to PET in the excited state
from lone electron pair on the nitrogen atom to the
anthracene fragment, which leads to quenching of
fluorescence in the latter [3, 4]. Interaction of such
compounds with metal cations or proton inhibits PET,
thus inducing strong fluorescence of the sensor [5, 6].
By reduction of Schiff bases Ia Ic we obtained
the corresponding N-substituted 9-aminomethylanthra-
cene derivatives IIa IIc. Compound IIa was brought
into reaction with phenyl isothiocyanate to obtain
sensor III having a thiourea fragment.
Cd2+ ions) sharply increase the relative fluorescence
intensity (see figure). In this case, the emission band
corresponding to exiplex completely disappears from
the spectrum of IIb. Compound III having a thiourea
fragment and hence capable of coordinating heavy
metal cations [8 10] selectively reacts with Hg2+ ions,
resulting in a 77-fold increase in the fluorescence
intensity. We can thus conclude that the obtained
9-aminomethylanthracene derivatives are new effec-
tive fluorescent chemosensors selective for Zn2+
(IIb and IIc) and Hg2+ ions (III).
R = Bzl (a), (CH2)2NHCH2Ant (b), (CH2)6NHCH2Ant (c);
Ant = 9-anthryl.
Chemosensors IIb, IIc, and III show a very weak
anthracene-like fluorescence in acetonitrile solution
on excitation at
355 nm (three maxima in the
excit
region 390 440 nm and a shoulder at 460 470 nm are
observed). The emission spectrum of diamine IIb also
contains a weak band at 470 600 nm, which is likely
to correspond to formation of exiplex [7]. Addition of
various d-metal acetates to solutions of compounds
Variation of the fluorescence intensity of compounds
(1) IIb, (2) IIc, and (3) III (c = 5 10 M) upon complex
5
5
IIb and IIc (5 10 M) favors further fluorescence
formation with metal cations in acetonitrile (
355 nm,
excit
decay, while Zn2+ ions (and, to a lesser extent,
418 nm).
fluor
1070-4280/03/3909-1364$25.00 2003 MAIK Nauka/Interperiodica

NEW FLUORESCENT CHEMOSENSORS
1365
N-[(1E)-9-Anthrylmethylene]-N-benzylamine
(Ia). A mixture of 4.12 g (20 mmol) of 9-anthralde-
hyde, 2.15 g (20 mmol) of benzylamine, and 50 ml
of toluene was heated for 2 h under reflux in a flask
equipped with a Dean Stark trap. The solvent was
distilled off under reduced pressure (water-jet pump),
and the residue was recrystallized from 1-butanol.
Yield 5.15 g (87%). mp 177 178 C. IR spectrum, ,
cm : 1455, 1360. H NMR spectrum (DMSO-d6), ,
ppm: 5.38 s (2H, CH2), 6.93 8.64 m (14H, Harom),
9.61 s (1H, CH). Found, %: C 89.4; H 5.8; N 4.7.
C22H17N. Calculated, %: C 89.5; H 5.8; N 4.7.
N-Bis(9-anthrylmethylene)ethane-1,2-diamine
(IIb). Sodium tetrahydridoborate, 1.13 g (30 mmol),
was added in small portions to a suspension of 2.18 g
(5 mmol) of Schiff base Ib in 100 ml of ethanol DMF
(3:1), stirred at 60 70 C. The mixture was stirred
for 3 h at that temperature and diluted with water
(200 ml), and excess NaBH4 was decomposed with
acetic acid. The precipitate was filtered off, dried,
and recrystallized from 1-butanol. Yield 1.67 g (76%).
1
1
1
mp 183 184 C. IR spectrum, , cm : 1330, 1235.
1H NMR spectrum (DMSO-d6), , ppm: 3.06 s
[4H, (CH2)2], 4.71 s (4H, 2CH2), 7.20 8.45 m (18H,
N,N-Bis[(1E)-9-anthrylmethylene]ethane-1,2-di-
amine (Ib). A mixture of 4.12 g (20 mmol) of 9-an-
thraldehyde, 0.5 ml of acetic acid, and 0.6 g
(10 mmol) of ethylenediamine in 50 ml of ethanol
was heated for 2 h under reflux. The precipitate was
filtered off and recrystallized from 1-butanol DMF
(1:1). Yield 4.09 g (94%). mp 145 146 C. IR spec-
trum, , cm : 1633, 1447, 1360. H NMR spectrum
(DMSO-d6), , ppm: 4.43 s [4H, (CH2)2], 7.12
8.62 m (18H, Harom), 9.52 s (2H, 2CH). Found, %:
C 88.0; H 5.4; N 6.3. C32H24N2. Calculated, %:
C 88.0; H 5.5; N 6.4.
H
arom). Found, %: C 87.1; H 6.4; N 6.2. C32H28N2.
Calculated, %: C 87.2; H 6.4; N 6.4.
N-Bis(9-anthrylmethylene)hexane-1,6-diamine
(IIc) was synthesized as described above for com-
pound IIb. Yield 2.02 g (81%). mp 137 138 C. IR
spectrum, , cm : 3385, 1485, 1328, 1220. H NMR
spectrum (CDCl3), , ppm: 1.22 1.72 m [8H, (CH2)4],
2.87 t (4H, 2CH2), 4.71 s (4H, 2CH2), 7.18 8.45 m
(18H, Harom). Found, %: C 87.1; H 7.3; N 5.7.
C36H36N2. Calculated, %: C 87.0; H 7.3; N 5.6.
N-(9-Anthrylmethyl)-N-benzyl-N -phenylthio-
urea (III). A mixture of 1.48 g (5 mmol) of amine
IIa and 0.68 g (5 mmol) of phenyl isothiocyanate in
30 ml of benzene was heated for 2 h under reflux. It
was then cooled, and the product was filtered off and
recrystallized from 1-butanol. Yield 85%. mp 191
1
1
1
1
N,N-Bis[(1E)-9-anthrylmethylene]hexane-1,6-di-
amine (Ic) was synthesized as described above for
compound Ib. Yield 4.47 g (91%). mp 151 152 C.
1
1
IR spectrum, , cm : 1620, 1460, 1360. H NMR
spectrum (DMSO-d6), , ppm: 1.67 m [4H, (CH2)2],
1.96 m (4H, 2CH2), 3.95 t (4H, 2CH2), 7.38 8.62 m
(18H, Harom), 9.42 s (2H, 2CH). Found, %: C 87.9;
H 6.5; N 5.6. C36H32N2. Calculated, %: C 87.8;
H 6.5; N 5.7.
1
192 C. IR spectrum, , cm : 3320, 1455, 1378, 1305.
1H NMR spectrum (DMSO-d6), , ppm: 4.56 s (2H,
CH2), 6.17 s (2H, CH2), 6.88 8.60 m (19H, Harom),
9.46 s (1H, NH). Found, %: C 80.6; H 5.6; N 6.3;
S 7.4. C29H24N2S. Calculated, %: C 80.5; H 5.6;
N 6.4; S 7.4.
N-(9-Anthrylmethyl)-N-benzylamine hydro-
chloride (IIa HCl). Sodium tetrahydridoborate,
1.13 g (30 mmol), was added with stirring to a sus-
pension of 2.95 g (10 mmol) of Schiff base Ia in
100 ml of ethanol. The mixture was stirred for 4 h
and diluted with water (200 ml), and excess NaBH4
was decomposed with acetic acid. Product IIa was
extracted into chloroform (3 50 ml), the extract was
washed with water and dried over anhydrous Na2SO4,
the solvent was distilled off, and the residue was
dissolved in 50 ml of benzene. The solution was
saturated with hydrogen chloride over a period of
2 h, and the precipitate was filtered off, dried, and
recrystallized from 1-butanol. Yield 2.45 g (73%).
The IR spectra were recorded on a Specord 75IR
spectrometer from samples pelleted with KBr. The
fluorescence spectra were measured from solutions
in acetonitrile on a Hitachi 650-60 spectrofluorimeter.
The 1H NMR spectra were obtained on a Varian
Unity-300 instrument (300 MHz) using tetramethyl-
silane as reference.
This study was financially supported by the
Ministry of Education of the Russian Federation
(project no. E02-12.6-259) and by the CRDF (project
no. REC-004).
1
mp 225 226 C. IR spectrum, , cm : 3435, 3200,
1
1457, 1385. H NMR spectrum (DMSO-d6), , ppm:
REFERENCES
4.38 t (2H, CH2), 5.08 t (2H, CH2), 7.40 8.70 m
(14H, Harom), 9.96 br.s (2H, NH2). Found, %: C 79.0;
H 6.0; Cl 10.4; N 4.1. C22H20ClN. Calculated, %:
C 79.1; H 6.0; Cl 10.6; N 4.2.
1. De Silva, A.P., Gunaratne, H.Q.N., Gunnlaugsson, T.,
Huxley, A.J.M., McCoy, C.P., Rademacher, J.T., and
Rice, T.E., Chem. Rev., 1997, vol. 97, p. 1515.
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 39 No. 9 2003

1366
TOLPYGIN et al.
2. Bren’, V.A., Usp. Khim., 2001, vol. 70, p. 1152.
7. Lahlou, S., Bitit, N., and Desvergne, J.-P., J. Chem.
Res., Synop., 1998, p. 302.
3. Fabrizzi, L., Licchelli, M., and Pallavicini, P., Acc.
Chem. Res., 1999, vol. 32, p. 846.
8. Henderson, W., Nickolson, B.K., and Rickard, C.E.E.,
Inorg. Chim. Acta, 2001, vol. 320, p. 101.
4. De Silva, A.P., Fox, D.B., Moody, T.S., and
Weir, S.M., Trends Biotechnol., 2001, vol. 19, p. 29.
9. Gunnlaugsson, N.T., Davis, A.P., and Glynn, M.,
J. Chem. Soc., Chem. Commun., 2001, p. 2556.
5. Pina, F., Bernardo, M.A., and Garcia-Espana, E., Eur.
J. Inorg. Chem., 2000, p. 2143.
10. Nishizawa, S., Kaneda, H., Uchida, T., and
Terame, N., J. Chem. Soc., Perkin Trans. 2, 1998,
p. 2325.
6. Kimura, E. and Koike, T., Chem. Soc. Rev., 1998,
vol. 27, p. 179.
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