2-Acetamido-5-methylbenzaldehyde

Acetamido-5-methylbenzaldehyde trimethylene mercaptal. Into a 25-ml round-bottomed flask are placed 300 mg of the foregoing amino compound, 5 ml of acetic anhydride and 3 ml of pyridine. The solution is heated on a steam bath for 5 minutes, allowed to cool and poured into 50 ml of water, whereupon the product precipitates. Sodium carbonate is added until the solution is basic. The product is collected by filtration, washed with water and dried under vacuum (320 mg, 90%). Further recrystallisation affords fine, white crystals, m.p. 159-160°C. 

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