反応 #50227

反応方程式

2-ethoxybenzoyl chloride

4-amino-1-methyl-3-n-propylpyrazole-5-carboxamide

triethylamine

→

pyrazole-5-carboxamide

収率 40.6%

4-(2-Ethoxybenzamido)-1-methyl-3-n-propylpyrazole-5-carboxamide

収率 40.6%

溶媒

dichloromethane

dichloromethane

反応条件

後処理

1. 1
   その他The solvent was evaporated under vacuum
2. 2
   workup.DISSOLUTIONthe residue dissolved in a 19:1 mixture of dichloromethane and methanol (250 ml)
3. 3
   洗浄the solution washed with 1N hydrochloric acid (100 ml)
4. 4
   乾燥dried (MgSO4)
5. 5
   その他evaporated under vacuum
6. 6
   その他The crude material was chromatographed on silica gel (200 g)
7. 7
   洗浄eluting with a 97:3 mixture of dichloromethane and methanol
8. 8
   その他to give a pink solid
9. 9
   その他crystallisation from ethyl acetate-hexane

実験手順

A solution of 2-ethoxybenzoyl chloride (6.1 g, 33.0 mmol) in dichloromethane (50 ml) was added to a stirred solution of 4-amino-1-methyl-3-n-propylpyrazole-5-carboxamide (3.0 g, 16.4 mmol), 4-dimethylaminopyridine (0.02 g, 0.164 mmol) and triethylamine (3.34 g, 33.0 mmol) in dichloromethane (50 ml) at 0° C. The resulting mixture was allowed to warm to room temperature and stirred for a further 2 hours. The solvent was evaporated under vacuum, the residue dissolved in a 19:1 mixture of dichloromethane and methanol (250 ml), and then the solution washed with 1N hydrochloric acid (100 ml), dried (MgSO4) and evaporated under vacuum. The crude material was chromatographed on silica gel (200 g), eluting with a 97:3 mixture of dichloromethane and methanol, to give a pink solid; crystallisation from ethyl acetate-hexane gave the pyrazole-5-carboxamide as a pale pink solid (2.2 g, 40%), m.p. 153°-155° C. Found: C,61.66; H,6.77; N,16.95. C17H22N4O3 requires C,61.80; H,6.71; N,16.96%.

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