organic chemistry issues discussion for professional scientists
Нужно получить 2-аминобензальдегид в достаточном количестве.
Нашлась следующая методика:
2-nitrobenzaldehyde (302 mg, 2.0 mmol) was dissolved in ethanol (5.7 mL) and the solution was stirred for approximately 1 minute. Iron powder (335 mg, 6.0 mmol) and dilute hydrochloric acid (2 mL of 0.15 M HCl, 0.3 mmol) were added to the stirred solution. The reaction was heated to reflux for 1 hour after which time all of the staring material had been reduced. The reaction was cooled to room temperature and stirred for 0.5 hours. The cooled solution was diluted with ethyl acetate (16.5 mL) and stirred for 5 minutes before being filtered through a short celite plug. The filtrate was concentrated to approximately 1.5 mL and then rapidly passed through a short silica plug, eluting with 1/5 v/v ethyl acetate/hexane. The solvent was evaporated under reduced pressure to yield a yellow solid 12 (238 mg, 1.96 mmol, 98percent). m.p. 190-192.
Выглядит она на первый взгляд очень даже эротично, но есть один вопрос - а почему аминоальдегид в кипящем спирте не умирает?
P.S.: окисление оксидом марганца не предлагать
Тому, кто тверд во грехе, раскаяние не нужно.
Upd. From SF:
2-Nitrobenzaldehyde S8 (2.92 g, 19.32 mmol) and iron powder (7.55 g, 135.2 mmol) were placed inside a round bottom flask equipped with a condenser together with 45 mL ethanol, 45 mL acetic acid and 22.5 mL water. The solution was stirred for 5 min at reflux and then stirred for ca. 15 min without heating until it cooled down to room temperature. The mixture was filtered and the residue washed with ethyl acetate. Then 300 mL water were added to the obtained dark solution and extracted with ethyl acetate. The combined organic layers were washed neutral with saturated NaHCO3 solution, dried over MgSO4, filtered and the solvent removed under reduced pressure. A crude product of S9 was obtained and used immediately without further purification in step 3. Yellow oil (2.48 g).
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