53% |
With sulfuric acid; In water; at 120℃; for 0.333333h; |
Concentrated sulfuric acid (3 mL) was carefully added to a suspension of 2- amino-4-methylbenzonitrile (800 mg, 6.1 mmol) in H2O (1 mL). The solution was then placed into an oil bath, pre-heated to 120 0C, the reaction stirred for 20 min and then immediately cooled in an ice bath. The solution was made basic via the addition of 5 percent NaOH and the resulting solid collected via vacuum filtration. 484.4 mg (53 percent) of the title compound as a light brown solid were obtained. 1H NMR (DMSO-dbeta) delta 7.63 (br s, 1 H), 7.42 (d, 1 H), 6.95 (br s, 1 H), 6.55 (br s, 2 H), 6.45 - 6.48 (m, 1 H), 6.29 (ddd, 1 H), 2.16 (s, 3 H). MS (ES) 134 (M - 16). |
43% |
With potassium hydroxide; In ethanol; for 8h;Reflux; |
2-amino-4-methylbenzonitrile (10 g, 75.7 mmol) was dissolved in ethanol, added with potassium hydroxide (21.2 g, 378 mmol), followed by refluxing for 8 hours. The reaction mixture was cooled to room temperature, concentrated under reduced pressure, and dissolved in ethyl acetate. The organic layer formed was washed with a saturated aqueous solution of sodium bicarbonate and brine. The obtained organic layer is dried over anhydrous sodium sulfate, concentrated under reduced pressure, and recrystallized from ethanol to obtain the title compound (4.9 g, 43percent). 1H-NMR Spectrum (300 MHz, DMSO- 6): delta 7.40 (d, 1H), 6.52 (s, 2H), 6.45 (s, 1H), 6.28 (d, lH), 2.14 (s, 3H) |
43% |
With potassium hydroxide; In ethanol; for 8h;Reflux; |
2-amino-4-methylbenzonitrile (10 g, 75.7 mmol) was dissolved in ethanol, added with potassium hydroxide (21.2 g, 378 mmol), followed by refluxing for 8 hours. The reaction mixture was cooled to room temperature, concentrated under reduced pressure, and dissolved in ethyl acetate. The organic layer formed was washed with a saturated aqueous solution of sodium bicarbonate and brine. The obtained organic layer is dried over anhydrous sodium sulfate, concentrated under reduced pressure, and recrystallized from ethanol to obtain the title compound (4.9 g, 43percent). 1H-NMR Spectrum (300 MHz, DMSO-d6): delta 7.40 (d, 1H), 6.52 (s, 2H), 6.45 (s, 1H), 6.28 (d, 1H), 2.14 (s, 3H) |