반응 #50213

반응 방정식

5-(5-bromo-2-ethoxyphenyl)-1-methyl-3-n-propyl-1,6-dihydro-7H-pyrazolo[4,3-d]pyrimidin-7-one

imidazole

potassium carbonate

iodine

→

title compound

수율 38.0%

5-[2-Ethoxy-5-(1-imidazolyl)phenyl]-1-methyl-3-n-propyl-1,6-dihydro-7H-pyrazolo[4,3-d]pyrimidin-7-one

수율 38.0%

용매

water

dimethylformamide

반응 조건

후처리

1. 1
   온도under reflux under nitrogen for 4.5 hours
2. 2
   온도cooled
3. 3
   추출This mixture was extracted with a 9:1 mixture of dichloromethane and methanol (6×50 ml)
4. 4
   건조dried (MgSO4)
5. 5
   기타evaporated under vacuum
6. 6
   기타to give a pale brown oil
7. 7
   기타The oil was chromatographed on silica gel (20 g)
8. 8
   세척eluting with a mixture of dichloromethane, methanol and triethylamine (97.8:20:0.2)
9. 9
   기타to give
10. 10
    기타a yellow solid, crystallisation of which from ethyl acetate-hexane

실험 절차

A solution of 5-(5-bromo-2-ethoxyphenyl)-1-methyl-3-n-propyl-1,6-dihydro-7H-pyrazolo[4,3-d]pyrimidin-7-one (0.20 g, 0.0051 mol), imidazole (0.172 g, 0.0025 mol), anhydrous potassium carbonate (0.077 g, 0.00056 mol), copper bronze (0.036 g, 0.00057 mol) and iodine (0.015 g, 0.00012 mol) in dimethylformamide (10 ml) was heated under reflux under nitrogen for 4.5 hours, cooled and poured into water (50 ml). This mixture was extracted with a 9:1 mixture of dichloromethane and methanol (6×50 ml) and the extracts combined, dried (MgSO4) and evaporated under vacuum to give a pale brown oil. The oil was chromatographed on silica gel (20 g), eluting with a mixture of dichloromethane, methanol and triethylamine (97.8:20:0.2), to give a yellow solid, crystallisation of which from ethyl acetate-hexane gave the title compound as a cream solid (0.073 g, 38%), m.p. 193°-194° C. Found: C,63.61; H,5.97; N,22.03. C20H22N6O2 requires C,63.48; H,5.86; N,22.21%.

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