Lattice energetics and thermochemistry of acridine derivatives and substituted acridinium...
chloride. The insoluble residue was extracted with toluene.
The organic phase was washed with water (100 mL) and
dried over sodium sulphate. After evaporation of the sol-
vent, the crude product was purified by column chro-
matography (eluent n-hexane/ethyl acetate = 5/1 v/v).
9-Benzylacridine (5) A mixture of 10 g of diphenylamine
(59.1 mmol), an equimolar amount of phenylacetic acid
(7.70 g, 59.0 mmol) and anhydrous zinc chloride (30.8 g,
226.0 mmol) was heated at 210 °C for 24 h. The reaction
mixture was digested with hot 10% aqueous sulphuric acid
and then strongly alkalified with concentrated aqueous
ammonia to dissolve the zinc chloride. The insoluble
residue was extracted with toluene. The organic phase was
washed with water (100 mL) and dried over sodium sul-
phate. After evaporation of the solvent, the crude product
was purified by gravitational column chromatography
Yield 81%; the % of elements found/calculated, C 86.93/
1
8
7.01, H 5.74/5.74, N 7.09/7.25; H NMR (CD CN), d,
3
ppm (J, Hz): 3.06 (3H, s); 7.52 (2H, t, J = 7.5); 7.71 (2H, t,
J = 7.4); 8.04 (2H, d, J = 8.6); 8.28 (2H, d, J = 8.8).
9
-Bromomethylacridine (2) To a solution of 9-methy-
lacridine (0.193 g, 1 mmol) in dichloromethane (10 mL)
was added N-bromosuccinimide (0.178 g, 1 mmol) portion-
wise in an ice-water bath. After complete addition, the
solution mixture was warmed to room temperature and
stirred overnight. The resulting solution was washed with
water and brine. The organic phase was dried over anhydrous
sodium sulphate, and the solvent was removed. The residue
was purified by column chromatography (eluent ethyl acet-
ate/petroleum ether = 1/5 v/v). Yield 77%; the % of ele-
(
eluent cyclohexane/ethyl acetate = 5/2 v/v). Yield 84%;
the % of elements found/calculated, C 89.27/89.19, H 5.58/
1
5
.61, N 5.15/5.20; H NMR (CDCl ), d, ppm (J, Hz): 4.21
3
(2H, s); 7.09 (2H, t, J = 7.5); 7.18 (2H, d, J = 8.9); 7.23
(2H, t, J = 7.5); 7.31 (5H, m); 7.92 (2H, d, J = 8.9).
9-Phenylacridine (6) A mixture of dimethyl phthalate
(20 mmol), diphenylamine (10 mmol), benzoic acid
(10 mmol) and zinc chloride (20 mmol) was stirred and
microwave irradiated at 100 °C and 120 W for 2 h. The
mixture was diluted with dichloromethane, washed with
water, diluted with sodium hydroxide, washed again with
water and dried over magnesium sulphate. After evapora-
tion of the solvent, the crude product was recrystallised
from toluene/ethanol. Yield 65%; the % of elements
ments found/calculated, C 61.26/61.79, H 3.64/3.70, N 5.03/
1
5
.15; H NMR (CDCl ), d, ppm (J, Hz): 5.38 (2H, s); 7.62
3
(
2H, t, J = 7.7); 7.78 (2H, t, J = 7.7); 8.31 (4H, d, J = 8.8).
-Ethylacridine (3) A mixture of 0.17 g of dipheny-
lamine (1 mmol), 1.1 mL propionic acid (15 mmol) and
.46 g zinc chloride (3 mmol) was stirred and microwave
9
0
found/calculated, C 89.42/89.38, H 5.10/5.13, N 5.48/5.49;
1
irradiated at 110 °C and 120 W for 2 h. The mixture was
diluted with dichloromethane, washed with water, diluted
with sodium hydroxide, washed again with water and dried
over magnesium sulphate. After evaporation of the solvent,
the crude product was purified by column chromatography
H NMR (CDCl ), d, ppm (J, Hz): 7.21 (1H, m); 7.39 (2H,
3
m); 7.42 (2H, m); 7.57 (2H, m); 7.69 (2H, dd, J = 11.8);
7
.74 (2H, m), 8.28 (2H, dd, J = 11.8).
9-Phenoxyacridine (7) In phenol (1.27 mol), 7.2 g
(180 mmol) of sodium hydroxide was dissolved at 100 °C,
and 9-chloroacridine (28 g, 131 mmol) added with stirring.
The solution was kept at 100 °C for 1.5 h, then poured into
2 M sodium hydroxide (500 mL), stirred and set aside
overnight. The precipitated material was filtered off,
washed with water, powdered and dried. The crude product
was purified by gravitational column chromatography
(
eluent 1–3% 2-propanol in chloroform). Yield 87%; the %
of elements found/calculated, C 86.69/86.92, H 6.34/6.32,
1
N 6.71/6.76; H NMR (CDCl ), d, ppm (J, Hz): 1.47 (3H, t,
3
J = 7.7); 3.65 (2H, q, J = 7.7); 7.56 (2H, t, J = 7.7); 7.77
(
2H, t, J = 8.0); 8.26 (4H, d, J = 8.8).
-Vinylacridine (4) To suspension of 0.535 g
1.5 mmol) triphenylmethylphosphonium bromide in
0 mL dry diethyl ether was added 0.168 g (1.5 mmol) of
potassium tert-butylate and stirred for 30 min. Then
.207 g (1.0 mmol) acridine-9-carboxaldehyde was added,
9
a
(
(eluent toluene/methanol = 10/1 v/v). Yield 78%; the % of
1
elements found/calculated, C 84.19/84.11, H 4.81/4.83, N
1
5
.20/5.16; H NMR (DMSO-d6), d, ppm (J, Hz): 6.88 (2H,
d, J = 8.6); 7.08 (1H, t, J = 7.5); 7.32 (2H, t, J = 7.5);
.59 (2H, t, J = 7.5); 7.88 (2H, t, J = 7.5); 8.04 (2H, d,
0
and the mixture stirred at ambient temperature overnight.
After dilution with 50 mL dichloromethane, the solution
was washed with water three times, after which the organic
layer was separated, dried over magnesium sulphate and
evaporated to dryness. The target compound was purified
by column chromatography (eluent 1% 2-propanol in
chloroform). Yield 73%; the % of elements found/calcu-
7
J = 8.9); 8.23 (2H, d, J = 8.6).
9-Piperidylacridine (8) In 2 mL piperidine, 0.213 g
(1.0 mmol) of 9-chloroacridine hydrochloride was dis-
solved and heated to 90 °C with constant stirring for 6 h.
The solvent was evaporated under vacuum at 50 °C. The
residue was washed with aqueous methanol and dried in a
vacuum. Yield 91%; the % of elements found/calculated, C
1
lated, C 87.27/87.77, H 5.66/5.40, N 6.48/6.82; H NMR
(
CDCl ), d, ppm (J, Hz): 5.60 (1H, d, J = 11.8); 5.98 (1H,
3
1
d, J = 11.8); 7.32 (1H, dd, J = 11.8); 7.39 (2H, t, J = 7.5);
.65 (2H, t, J = 7.5); 8.13 (4H, d, J = 8.9).
81.96/82.41, H 7.01/6.92, N 10.93/10.68; H NMR
7
(CDCl3), d, ppm (J, Hz): 1.80 (2H, m); 1.84 (4H, m); 3.59
123