Synthesis of Benzo[f]indole-4,9-dione and Benzo[b]carbazole-6,11-dione ­Derivatives via One-Pot Sequential C,N-Dialkylation of Enaminones of β-Diketones and Ketoesters by 2,3-Dichloronaphthoquinone

Abstract

Direct one-pot syntheses of benzo[f]indole-4,9-dione and benzo[b]carbazole-6,11-dione derivatives have been achieved in moderate to high yields via sequential C,N-dialkylation of the monoenamines of β-dicarbonyl compounds (the β-enaminones) by 2,3-dichloronaphthoquinone

benzo[f]indole-4,9-dione - benzo[b]carbazole-6,11-dione - enaminone - 2,3-dichloronaphthoquinone - C,N-dialkylation

References and Notes

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<A NAME="RW04506ST-28">28</A>

General Procedures for the Synthesis of 3. A mixture of 1 (1.1 mmol), 2 (1 mmol) and Na₂CO₃ (2.5 mmol) in DMF (15 mL) was heated at 80 °C for 6 h with magnetic stirring and TLC monitoring of the reaction, the solvent was removed under reduced pressure, and the residual solid was separated by flash chromatography on a silica gel column with PE (bp 60-90 °C)-EtOAc as eluent to give the product.
General Procedures for the Synthesis of 7 and 8. A mixture of 1 (1.1 mmol), 6 (1 mmol) and Na₂CO₃ (2.5 mmol) in MeCN (15 mL) was heated under reflux for 8 h. The reaction mixture was poured into H₂O and the pH of the aqueous solution was adjusted to 5 by adding aq HCl. Work-up of the residual solid as above gave the products.

<A NAME="RW04506ST-29">29</A>

Analytical and Spectroscopic Data of New Compounds Prepared. Compound 3b: yellow solid, mp 209-210 °C. ¹H NMR (300 MHz, CDCl₃): δ = 2.21 (s, 3 H), 2.81 (s, 3 H), 3.92 (s, 3 H), 7.08 (d, 2 H, J = 8.8 Hz), 7.21 (d, 2 H, J = 8.8 Hz), 7.64-7.74 (m, 2 H), 8.02 (dd, 1 H, J = 7.1, 1.6 Hz), 8.19 (dd, 1 H, J = 7.1, 1.4 Hz). ¹³C NMR (75 MHz, CDCl₃): δ = 12.2, 32.2, 55.9, 115.1, 122.9, 125.5, 126.6, 127.1, 128.5, 129.8, 131.5, 133.5, 133.6, 133.7, 134.0, 143.4, 160.6, 175.4, 181.3, 199.4. IR (KBr): ν = 3302, 3096, 3066, 3005, 2962, 2934, 2837, 1665, 1589, 1515, 1495, 1459, 1430, 1281, 1246, 1212 cm^-1. MS: m/z (%) = 359 [M⁺, base], 344 (87), 328 (16), 273 (15), 238 (7), 217 (6), 127 (8), 92 (9), 77 (14). Anal. Calcd for C₂₂H₁₇NO4: C, 73.54; H, 4.74; N, 3.90. Found: C, 73.55; H, 4.63; N, 4.00.
Compound 3c: yellow solid, mp 254-256 °C. ¹H NMR (300 MHz, CDCl₃): δ = 2.22 (s, 3 H), 2.72 (s, 3 H), 2.81 (s, 3 H), 7.42 (d, 2 H, J = 8.4 Hz), 7.65-7.75 (m, 2 H), 8.00 (dd, J = 7.5, 1.5 Hz), 8.18-8.20 (m, 3 H). ¹³C NMR (100 MHz, CDCl₃): δ = 11.8, 26.8, 31.8, 123.0, 125.4, 126.3, 126.9, 127.7, 129.7, 131.0, 132.8, 133.4, 133.5, 133.6, 137.8, 140.8, 142.3, 175.0, 180.8, 196.7, 198.8. IR (KBr): ν = 3349, 3321, 3091, 3063, 3032, 3003, 1686, 1670, 1651, 1602, 1589, 1525, 1498, 1426, 1356, 1281, 1267, 1246, 1212, 1116 cm^-1. MS: m/z (%) = 371 [M⁺, base], 356 (85), 328 (14), 310 (11), 228 7), 171 (7), 127 (7), 76 (10). Anal. Calcd for C₂₃H₁₇NO₄: C, 74.39; H, 4.58; N, 3.77. Found: C, 74.46; H, 4.78; N, 3.77.
Compound 5a: yellow solid, mp 259-260 °C. ¹H NMR (300 MHz, CDCl₃): δ = 1.11 (s, 6 H), 2.48 (s, 2 H), 2.56 (s, 2 H), 7.33-7.36 (m, 2 H), 7.61-7.66 (m, 4 H), 7.71 (td, J = 7.4, 1.4 Hz), 7.98 (dd, J = 7.5, 1.2 Hz), 8.27 (dd, J = 7.5, 1.3 Hz). ¹³C NMR (75 MHz, CDCl₃): δ = 28.7, 35.2, 36.9, 53.8, 118.5, 126.4, 127.3, 127.7, 130.1, 133.0, 133.4, 134.1, 134.3, 137.0, 151.4, 176.2, 179.5, 191.7. IR (KBr): ν = 3320, 3085, 2959, 2934, 2871, 1682, 1668, 1591, 1497, 1467, 1284,1268, 1202 cm^-1. MS: m/z (%) = 369 [M⁺], 313 (100), 312 (45), 285 (18), 77 (13). Anal. Calcd for C₂₄H₁₉NO₃: C, 78.05; H, 5.15; N, 3.79. Found: C, 78.08; H, 5.25; N, 3.74.
Compound 5b: yellow solid, mp 258-260 °C. ¹H NMR (300 MHz, CDCl₃): δ = 1.11 (s, 6 H), 2.49 (s, 2 H), 2.55 (s, 2 H), 3.93 (s, 3 H), 7.09 (d, 2 H, J = 8.8 Hz), 7.25 (d, 2 H, J = 8.8 Hz), 7.64 (td, 1 H, J = 7.4, 0.9 Hz), 7.71 (td, 1 H, J = 7.4, 1.0 Hz), 7.98 (d, 1 H, J = 7.5 Hz), 8.25 (d, 1 H, J = 7.2 Hz). ¹³C NMR (100 MHz, CDCl₃): δ = 28.3, 34.7, 36.6, 53.4, 55.6, 114.8, 117.9, 125.0, 126.0, 127.2, 128.0, 129.1, 132.6, 133.0, 133.6, 133.7, 133.9, 151.4, 160.3, 175.9, 179.2, 191.4. IR (KBr): ν = 3317, 3064, 3011, 2955, 2935, 2896, 2868, 2838, 1686, 1660, 1608, 1588, 1514, 1497, 1469, 1304, 1283, 1268, 1251, 1202, 1172 cm^-1. MS: m/z (%) = 399 [M⁺], 343 (100), 300(9), 105 7), 85 (7), 77 (7), 55 (9), 44 (82). Anal. Calcd for C₂₅H₂₁NO₄: C, 75.19; H, 5.26; N, 3.51. Found: C, 75.24; H, 5.32; N, 3.30.
Compound 5c: yellow solid, mp 268-269 °C. ¹H NMR (300 MHz, CDCl₃): δ = 1.10 (s, 6 H), 2.47 (s, 2 H), 2.53 (s, 2 H), 7.32 (d, 2 H, J = 8.6 Hz), 7.58 (d, 2 H, J = 8.6 Hz), 7.63 (dd, 1 H, J = 7.5, 1.4 Hz), 7.69 (td, 1 H, J = 7.5, 1.3 Hz), 7.93 (dd, 1 H, J = 7.5, 1.3 Hz), 8.21 (dd, 1 H, J = 7.6, 1.2 Hz). ¹³C NMR (100 MHz, CDCl₃): δ = 28.3, 34.8, 36.6, 53.3, 118.3, 125.2, 126.0, 127.3, 128.3, 130.0, 132.4, 133.1, 133.6, 133.8, 133.9, 135.0, 135.9, 150.8, 175.9, 179.0, 191.2. IR (KBr): ν = 3306, 3112, 3091, 3060, 3043, 2956, 2928, 2896, 2870, 1684, 1660, 1591, 1496, 1465, 1421, 1300, 1283, 1266, 1202 cm^-1. MS: m/z (%) = 405 [M + 2], 403 [M⁺], 388 (10), 347 (100), 319 (15), 284 (11), 126 (10). Anal. Calcd for C₂₄H₁₈ClNO₃: C, 71.38; H, 4.46; N, 3.47. Found: C, 71.40; H, 4.56; N, 3.56.
Compound 7a: yellow solid, mp 269-271 °C. ¹H NMR (300 HMz, CDCl₃): δ = 2.16 (quint, 2 H, J = 6.2 Hz), 2.61-2.70 (m, 4 H), 7.36-7.39 (m, 2 H), 7.60-7.65 (m, 4 H), 7.70 (td, 1 H, J = 7.4, 1.3 Hz), 7.96 (dd, 1 H, J = 7.5, 1.2 Hz), 8.24 (dd, 1 H, J = 7.7, 1.2 Hz). ¹³C NMR (100 MHz, CDCl₃): δ = 22.6, 22.8, 39.4, 119.0, 125.2, 125.9, 126.9, 127.2, 129.6, 129.7, 132.5, 132.9, 133.3, 133.7, 133.9, 136.6, 152.1, 175.8, 179.1, 191.7. IR (KBr): ν = 3309, 3048, 2952, 2872, 1684, 1661, 1593, 1496, 1470, 1278, 1208 cm^-1. MS: m/z (%) = 341 [M⁺], 339 (100), 313 (78), 285 (15), 254 (16), 228 (18), 180 (10), 152 (28), 126 (26), 105 (25), 77 (88). Anal. Calcd for C₂₂H₁₅NO₃: C, 77.42; H, 4.40; N, 4.11. Found: C, 77.27; H, 4.34; N, 4.21.
Compound 8a: red solid, mp >300 °C. ¹H NMR (300 MHz, CDCl₃): δ = 6.63 (d, 1 H, J = 8.5 Hz), 6.85 (d, 1 H, J = 7.9 Hz), 7.33 (t, 1 H, J = 8.2 Hz), 7.45 (t, 2 H, J = 4.0 Hz), 7.62-7.63 (m, 3 H), 7.75 (quint, 2 H, J = 6.9 Hz), 8.07 (d, 1 H, J = 7.1 Hz), 8.28 (d, 1 H, J = 6.9 Hz). ¹³C NMR (CDCl₃): δ = 103.3, 109.2, 114.7, 121.2, 127.3, 127.4, 127.8, 129.8, 130.0, 130.8, 133.2, 133.9, 134.2, 134.4, 137.0, 143.2, 153.3, 176.9, 183.8. IR (KBr): ν = 3043, 1668, 1620, 1589, 1578, 1495, 1430, 1270 cm^-1. MS: m/z (%) = 339 (100) [M⁺], 310 (14), 254 (11), 151 (7), 77 (11). Anal. Calcd for C₂₂H₁₃NO₃: C, 77.88; H, 3.83; N, 4.13. Found: C, 77.82; H, 3.75; N, 4.16.
Compound 7b: yellow solid, mp 265-266 °C (dec.). ¹H NMR (300 MHz, CDCl₃): δ = 2.09-2.19 (m, 2 H), 2.37 (dt, 1 H, J = 17.4, 5.4 Hz), 2.63 (d, J = 17.2 Hz), 2.72 (t, 2 H, J = 6.3 Hz), 7.17 (d, 1 H, J = 8.3 Hz), 7.48-7.74 (m, 6 H), 7.88 (d, 1 H, J = 7.6 Hz), 8.04 (d, 1 H, J = 8.1 Hz), 8.12 (d, 1 H, J = 8.3 Hz), 8.30 (d, 1 H, J = 7.6 Hz). ¹³C NMR (100 MHz, CDCl₃): δ = 22.2, 22.6, 39.4, 119.2, 121.2, 124.9, 125.3, 125.4, 126.0, 127.1, 127.4, 128.2, 128.8, 129.9, 130.3, 132.4, 132.9, 133.3, 133.7, 134.1, 134.3, 152.8, 175.7, 179.2, 191.7. IR (KBr): ν = 3376, 3057, 2952, 1686, 1666, 1593, 1496, 1474, 1282 cm^-1. MS: m/z (%) = 391 [M⁺], 363 (79), 334 (13), 278 (11), 95 (12), 69 (16), 43 (80). Anal. Calcd for C₂₆H₁₇NO₃: C, 79.80; H, 4.35; N, 3.58. Found: C, 79.82; H, 4.36; N, 3.57.
Compound 8b: red solid, mp 270-272 °C (dec.). ¹H NMR (300 MHz, CDCl₃): δ = 6.40 (d, 1 H, J = 8.3 Hz), 6.86 (d, 1 H, J = 7.8 Hz), 7.17 (d, 1 H, J = 8.5 Hz), 7.23-7.32 (m, 1 H), 7.40 (t, 1 H, J = 7.6 Hz), 7.54-7.64 (m, 2 H), 7.66-7.79 (m, 3 H), 7.94 (d, 1 H, J = 7.4 Hz), 8.04 (d, 1 H, J = 8.3 Hz), 8.13 (d, 1 H, J = 8.3 Hz), 8.31 (d, 1 H, J = 7.1 Hz), 10.90 (s, 1 H). ¹³C NMR (100 MHz, CDCl₃): δ = 103.1, 108.9, 114.4, 121.9, 125.4, 125.5, 126.9, 127.0, 127.6, 128.6, 130.1, 130.2, 130.5, 133.0, 133.3, 133.4, 133.8, 134.0, 134.4, 135.8, 143.3, 153.0, 176.2, 183.5. IR (KBr): ν = 3300, 3134, 3054, 2952, 1664, 1629, 1618, 1586, 1499, 1400, 1270, 1221 cm^-1. MS: m/z (%) = 389 [M⁺], 373 (11), 105 (10), 77 (13). Anal. Calcd for C₂₆H₁₅NO₃: C, 80.21; H, 3.86; N, 3.60. Found: C, 80.15; H, 3.91; N, 3.78.