Реакция #1094

Уравнение реакции

formic acid

acetic anhydride

N-tert-butyl-5-amino-2-methoxycarbonylbenzenesulfonamide

→

N-tert-Butyl-5-formylamino-2-methoxycarbonylbenzenesulfonamide

Растворители

DMF

Условия реакции

Обработка

1. 1
   ТемператураThe mixture is subsequently heated at 50°-60° C. for 2 h
2. 2
   ДругоеThe cooling bath is removed
3. 3
   workup.STIRRINGThe reaction mixture is then shaken up in 800 ml of ethyl acetate
4. 4
   Промывкаwashed with three times 150 ml of water
5. 5
   СушкаThe organic phase is dried over magnesium sulfate
6. 6
   workup.DISTILLATIONthe solvent is distilled off
7. 7
   Другоеthe residue is recrystallized from ethyl acetate/n-heptane

Методика

6.5 ml of formic acid are carefully added at 0° C. to 13 ml of acetic anhydride. The mixture is subsequently heated at 50°-60° C. for 2 h. A solution of 16.0 g (0.056 mol) of N-tert-butyl-5-amino-2-methoxycarbonylbenzenesulfonamide in 50 ml of DMF is then added dropwise at 0° C. The cooling bath is removed and the mixture is stirred for a further 4 h at room temperature. The reaction mixture is then shaken up in 800 ml of ethyl acetate and washed with three times 150 ml of water. The organic phase is dried over magnesium sulfate, the solvent is distilled off, and the residue is recrystallized from ethyl acetate/n-heptane. The product is N-tert-butyl-5-formylamino-2-methoxycarbonylbenzenesulfonamide (14.23 g, 82% of theory) which melts at 113°-114° C.

Источник