Symmetric Dinitro Tröger’s Base Analogues
were identical to those obtained for (Ϯ)-16 isolated from Method
A.
ArH) ppm. 13C NMR (100 MHz, CDCl3, 25 °C): δ = 17.8, 20.1,
55.7, 58.5, 66.2, 120.2, 120.9, 121.5, 126.7, 127.5, 129.3, 130.7,
130.9, 133.3, 146.1 ppm. C17H16N4O4 (340.33): calcd. C 59.99, H
4.74, N 16.49; found C 60.28, H 4.95, N 16.64.
4,10-Dimethoxy-1,7-dinitro-6H,12H-5,11-methanodibenzo[b,f][1,5]-
diazocine (17)
Method D: Starting with 4-methyl-3-nitroaniline (1.00 g,
6.57 mmol) and stirring for 7 d, 1H NMR of the crude material
obtained upon work-up (1.10 g) indicated that no Tröger’s base
product was present.
Method A: Starting with 2-methoxy-5-nitroaniline (2.00 g,
11.90 mmol), the crude material was chromatographed (silica gel,
dichloromethane) to afford (Ϯ)-17 (103 mg, 5%) as a pale yellow
1
solid; m.p. Ͼ308 °C (dec.). H NMR (400 MHz, CDCl3, 25 °C): δ
= 4.04 (s, 6 H, OCH3), 4.34 (app. s, 2 H, CH2), 4.67 (d, J = 18.6 Hz,
2 H, CH2), 4.91 (d, J = 18.6 Hz, 2 H, CH2), 6.85 (d, J = 9.2 Hz, 2
H, ArH), 7.99 (d, J = 9.2 Hz, 2 H, ArH) ppm. 13C NMR
(100 MHz, CDCl3, 25 °C): δ = 53.8, 56.5, 66.0, 108.5, 123.1, 126.5,
136.3, 140.7, 157.5 ppm. HRMS (FAB+ ): m/z calcd. for
C17H16N4O6 [M + Na]+, 395.096205; found 395.096136.
C17H16N4O6 (372.33): calcd. C 54.84, H 4.33, N 15.05; found C
54.91, H 4.44, N 14.98.
2,8-Diisopropyl-1,7-dinitro-6H,12H-5,11-methanodibenzo[b,f][1,5]-
diazocine (20)
Method A: Starting with 4-isopropyl-3-nitroaniline (900 mg,
4.99 mmol), the crude brown product was chromatographed (silica
gel, hexane/ethyl acetate, 3:1) to afford (Ϯ)-20 (75 mg, 8%) as a
pale yellow solid; m.p. 302–303 °C. 1H NMR (400 MHz, CDCl3,
25 °C): δ = 1.19 (d, J = 6.8 Hz, 6 H, 2ϫCH3), 1.23 (d, J = 6.8 Hz,
6 H, 2ϫCH3), 2.80–2.97 (m, 2 H, CH), 4.00 (d, J = 17.1 Hz, 2 H,
CH2), 4.25 (s, 2 H, CH2), 4.63 (d, J = 17.1 Hz, 2 H, CH2), 7.21 (d,
J = 8.5 Hz, 2 H, ArH), 7.26 (d, J = 8.5 Hz, 2 H, ArH) ppm. 13C
NMR (100 MHz, CDCl3, 25 °C): δ = 23.4, 23.8, 28.6, 55.0, 65.8,
118.9, 126.3, 127.7, 136.2, 146.3 ppm. HRMS (FAB+): m/z calcd.
for C21H24N4O4 [M + Na]+, 419.168976; found 419.16.168415.
Method D: Starting with 2-methoxy-5-nitroaniline (1.00 g,
5.95 mmol) and stirring for 5 d, the crude material was chromato-
graphed (silica gel, dichloromethane) to afford (Ϯ)-17 (254 mg,
22%) as a pale yellow solid; m.p. Ͼ308 °C (dec.). The spectroscopic
data on this material were identical to those obtained for (Ϯ)-17
isolated from Method A.
Method D: Starting with 4-isopropyl-3-nitroaniline (1.00 g,
4.59 mmol) and stirring for 7 d, the crude material was chromato-
graphed (silica gel, hexane/ethyl acetate, 4:1) to afford (Ϯ)-20
(516 mg, 45%) as a pale yellow solid; m.p. 302–303 °C. The spec-
troscopic data on this material were identical to those obtained for
(Ϯ)-20 isolated from Method A.
4,10-Dibromo-1,7-dinitro-6H,12H-5,11-methanodibenzo[b,f][1,5]di-
azocine (18)
Method A: Starting with 2-bromo-5-nitroaniline (1.00 g,
4.61 mmol), the crude material was chromatographed (silica gel,
hexane/dichloromethane, 1:9) to afford (Ϯ)-18 (103 mg, 10%) as a
pale yellow solid; m.p. Ͼ280 °C (dec.). 1H NMR (400 MHz,
CDCl3, 25 °C): δ = 4.40 (app. s, 2 H, CH2), 4.76 (d, J = 18.7 Hz,
2 H, CH2), 4.99 (d, J = 18.7 Hz, 2 H, CH2), 7.68 (d, J = 8.8 Hz, 2
H, ArH), 7.78 (d, J = 8.8 Hz, 2 H, ArH) ppm. 13C NMR
(100 MHz, CDCl3, 25 °C): δ = 54.6, 65.6, 122.3, 126.9, 127.5, 132.4,
146.4, 146.7 ppm. HRMS (FAB+): m/z calcd. for C15H10Br2N4O4
[M + Na]+, 490.896101; found 490.896087. C15H10Br2N4O4
(470.07): calcd. C 38.33, H 2.14, N 11.92; found C 38.12, H 2.32,
N 11.66.
2,8-Dibutyl-1,7-dinitro-6H,12H-5,11-methanodibenzo[b,f][1,5]diaz-
ocine (21)
Method B: Starting with 4-butyl-3-nitroaniline (950 mg,
4.89 mmol), the crude product was chromatographed (silica gel,
hexane/ethyl acetate, 3:1) to afford (Ϯ)-21 (182 mg, 18%) as a pale
yellow solid; m.p. 166–168 °C. 1H NMR (400 MHz, CDCl3, 25 °C):
δ = 0.89 (t, J = 7.3 Hz, 6 H, 2ϫCH3), 1.38–1.24 (m, 4 H, 2ϫCH2),
1.44–1.63 (m, 4 H, 2ϫCH2), 2.40–2.62 (m, 4 H, 2ϫCH2), 4.02 (d,
J = 17.2 Hz, 2 H, CH2), 4.27 (app. s, 2 H, CH2), 4.67 (d, J =
17.2 Hz, 2 H, CH2), 7.15 (d, J = 8.4 Hz, 2 H, ArH), 7.18 (d, J =
8.4 Hz, 2 H, ArH) ppm. 13C NMR (100 MHz, CDCl3, 25 °C): δ =
14.2, 22.9, 31.5, 33.2, 55.9, 66.2, 120.1, 128.1, 130.4, 131.5,
146.8 ppm. HRMS (FAB+): m/z calcd. for C23H28N4O4 [M +
Na]+, 447.200276; found 447.200812. C23H28N4O4 (424.49): calcd.
C 65.08, H 6.65, N 13.20; found C 65.35, H 6.77, N 13.29.
Method D: Starting with 2-bromo-5-nitroaniline (500 mg,
2.30 mmol) and stirring for 7 d, 1H NMR of the crude material
obtained upon work-up (514 mg) indicated that no Tröger’s base
product was present.
2,8–Dimethyl-1,7-dinitro-6H,12H-5,11-methanodibenzo[b,f][1,5]di-
azocine (19) and 2,8-Dimethyl-1,9-dinitro-6H,12H-5,11-methanodi-
benzo[b,f][1,5]diazocine (25)
Method D: Starting with 4-butyl-3-nitroaniline (1.00 g, 5.15 mmol)
and stirring for 11 d, 1H NMR of the crude material obtained upon
work-up (1.20 g) indicated that only a trace of Tröger’s base prod-
uct was present.
Method B: Starting with 4-methyl-3-nitroaniline (1.00 g,
6.57 mmol), the crude product was chromatographed (silica gel,
dichloromethane) to afford (Ϯ)-19 (315 mg, 32%) as an orange so-
lid; m.p. 230–232 °C. 1H NMR (400 MHz, CDCl3, 25 °C): δ = 2.76
(s, 6 H, CH3), 4.05 (d, J = 17.3 Hz, 2 H, CH2), 4.29 (app. s, 2 H,
CH2), 4.71 (d, J = 17.3 Hz, 2 H, CH2), 7.14 (d, J = 8.4 Hz, 2 H,
ArH), 7.18 (d, J = 8.4 Hz, 2 H, ArH) ppm. 13C NMR (100 MHz,
CDCl3, 25 °C): δ = 17.7, 55.7, 65.8, 120.2, 126.7, 127.7, 130.8,
146.4 ppm. C17H16N4O4 (340.33): C 59.99, H 4.74, N 16.49; found
C 60.06, H 4.96, N 16.71%.
2,8-Dibromo-1,7-dinitro-6H,12H-5,11-methanodibenzo[b,f][1,5]di-
azocine (22)
Method B: Starting with 4-bromo-3-nitroaniline (1.00 g,
4.61 mmol), the crude product was chromatographed (silica gel,
dichloromethane) to afford (Ϯ)-22 (57 mg, 6%) as a brown solid;
m.p. Ͼ300 °C (dec.). 1H NMR (400 MHz, CDCl3, 25 °C): δ = 4.16
(d, J = 17.1 Hz, 2 H, CH2), 4.36 (app. s, 2 H, CH2), 4.69 (d, J =
Another isomer, (Ϯ)-25 (91 mg, 9%) was subsequently eluted from
the column as a yellow solid; m.p. 242–244 °C. 1H NMR 17.1 Hz, 2 H, CH2) 7.49 (d, J = 8.8 Hz, 2 H, ArH), 7.69 (d, J =
(400 MHz, CDCl3, 25 °C): δ = 2.26 (s, 3 H, CH3), 2.47 (s, 3 H,
CH3) 4.07 (d, J = 17.3 Hz, 1 H, CH2), 4.17 (d, J = 17.3 Hz, 1 H,
CH2), 4.28 (app. s, 2 H, CH2), 4.67 (d, J = 17.3 Hz, 1 H, CH2),
4.72 (d, J = 17.3 Hz, 1 H, CH2), 6.87 (s, 1 H, ArH), 7.14 (d, J =
8.3 Hz, 1 H, ArH), 7.20 (d, J = 8.3 Hz, 1 H, ArH), 7.75 (s, 1 H,
8.8 Hz, 2 H, ArH) ppm. 13C NMR (100 MHz, DMSO, 25 °C): δ
= 54.4, 64.3, 106.4, 120.5, 122.0, 129.3, 132.5, 148.1 ppm. HRMS
(FAB+): m/z calcd. for C15H10Br2N4O4 [M + Na]+, 490.896101;
found 490.895153. C15H10Br2N4O4 (470.07): calcd. C 38.33, H
2.14, N 11.92; found C 38.33, H 2.18, N 11.68.
Eur. J. Org. Chem. 2009, 687–698
© 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjoc.org
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