تفاعل #3741

معادلة التفاعل

Oxalyl chloride

2-ethoxybenzoic acid

dimethylformamide

5-amino-1-n-propylimidazole-4-carboxamide

→

title compound

المردود 77.0%

5-(2-Ethoxybenzamido)-1-n-propylimidazole-4-carboxamide

المردود 77.0%

المذيبات

dichloromethane

pyridine

ظروف التفاعل

المعالجة

1. 1
   أخرىevaporated under vacuum
2. 2
   أخرىThe residue was azeotroped with dichloromethane (2×20 ml)
3. 3
   workup.STIRRINGwas stirred at ambient temperature for 3 days
4. 4
   أخرىevaporated under vacuum
5. 5
   workup.DISSOLUTIONThe residue was dissolved in dichloromethane (50 ml)
6. 6
   غسيلthe solution washed with 1N hydrochloric acid (30 ml)
7. 7
   تجفيفdried (Na2SO4)
8. 8
   أخرىevaporated under vacuum
9. 9
   غسيلa methanol in dichloromethane elution gradient (2-6% methanol)
10. 10
    أخرىfollowed by crystallisation from ethanol

الإجراء التجريبي

Oxalyl chloride (1.74 g, 0.137 mol) was added dropwise to a stirred solution of 2-ethoxybenzoic acid (1.1 g, 0.00663 mol) and dimethylformamide (0.1 ml) in dichloromethane (20 ml) and the resulting mixture stirred at ambient temperature for 4 hours, then evaporated under vacuum. The residue was azeotroped with dichloromethane (2×20 ml), then added dropwise to a stirred solution of 5-amino-1-n-propylimidazole-4-carboxamide (0.9 g, 0.00536 mol) in pyridine (20 ml) The resulting solution was stirred at ambient temperature for 3 days, then evaporated under vacuum. The residue was dissolved in dichloromethane (50 ml), and the solution washed with 1N hydrochloric acid (30 ml), dried (Na2SO4) and evaporated under vacuum. Chromatography of the crude product on silica gel (15 g) using a methanol in dichloromethane elution gradient (2-6% methanol), followed by crystallisation from ethanol, gave the title compound as a colourless solid (1.3 g, 77%), m.p. 182°-184° C. Found: C,60.85; H,6.40; N,18.06. C16H20N4O3 requires C,60.74; H,6.37; N,17.71%.

المصدر