تفاعل #302871

معادلة التفاعل

n-hexyl isocyanate

2-aminonicotinic acid methyl ester

→

3-hexyl-1H-pyrido[2,3-d]pyrimidine-2,4-dione

المردود 30.8%

المذيبات

pyridine

ظروف التفاعل

المعالجة

1. 1
   درجة الحرارةThe mixture was refluxed for 24 hours
2. 2
   أخرىThe pyridine was removed under reduced pressure
3. 3
   workup.ADDITIONthe residue was treated with 160 ml ethanol
4. 4
   درجة الحرارةThe mixture was refluxed for 10 minutes
5. 5
   أخرىThe crude 3-hexyl-1H-pyrido[2,3-d]pyrimidine-2,4-dione crystallized from the medium
6. 6
   أخرىwas purified by preparative column chromatography on straight phase silica (eluent:ethyl acetate:cyclohexane 1:2)
7. 7
   أخرى3-hexyl-1H-pyrido[2,3-d]pyrimidine-2,4-dione crystallized upon evaporation of the eluent

الإجراء التجريبي

17.46 g (137.3 mmol, 20 ml)n-hexyl isocyanate was added to a suspension of 5.31 g (34.9 mmol) 2-aminonicotinic acid methyl ester in 130 ml dry pyridine. The mixture was refluxed for 24 hours. The pyridine was removed under reduced pressure and the residue was treated with 160 ml ethanol. The mixture was refluxed for 10 minutes. The crude 3-hexyl-1H-pyrido[2,3-d]pyrimidine-2,4-dione crystallized from the medium and was purified by preparative column chromatography on straight phase silica (eluent:ethyl acetate:cyclohexane 1:2). 3-hexyl-1H-pyrido[2,3-d]pyrimidine-2,4-dione crystallized upon evaporation of the eluent. 2.66 g (310) of 3-hexyl-1H-pyrido[2,3-d]pyrimidine-2,4-dione was isolated (m.p. 166-168° C.)

المصدر