Réaction #1536358

Équation de réaction

formic acid acetic acid anhydride

2,4-diamino-5-(3,4,5-trimethoxybenzyl)-pyrimidine

water

→

4-amino-2-formamido-5-(3,4,5-trimethoxybenzyl)-pyrimidine

Rendement 75.5%

Solvants

pyridine

Conditions de réaction

Traitement

1. 1
   Autrereacted at 50° to 60° C. for two hours
2. 2
   Filtrationthe precipitate is filtered off
3. 3
   Autrerecrystallized from a mixture of dimethylformamide and water

Mode opératoire

2.64 g of formic acid/acetic acid anhydride are dripped, while cooling, into a suspension of 2.9 g of 2,4-diamino-5-(3,4,5-trimethoxybenzyl)-pyrimidine (trimethoprim) in 35 ml of pyridine and reacted at 50° to 60° C. for two hours. The reaction mixture is then poured into 400 ml of water and the precipitate is filtered off and recrystallized from a mixture of dimethylformamide and water. 2.4 g (75% of theory) of 4-amino-2-formamido-5-(3,4,5-trimethoxybenzyl)-pyrimidine of melting point 240° to 242° C. are obtained.

Source