Réaction #1094

Équation de réaction

formic acid

acetic anhydride

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

→

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

Solvants

DMF

Conditions de réaction

Traitement

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

Mode opératoire

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.

Source