반응 #673401

반응 방정식

sodium acetate trihydrate

1,1-dibromo-3,3,3-trifluoroacetone

NaOH

aminoguanidine bicarbonate

→

mixture

수율 53.1%

3-Amino-5-trifluoromethyl-1,2,4-triazine

수율 53.1%

용매

water

반응 조건

후처리

1. 1
   온도The solution was heated
2. 2
   온도at reflux under nitrogen for 30 min
3. 3
   여과The solid was collected by filtration
4. 4
   세척washed with water
5. 5
   기타dried at 60° C. under vacuum

실험 절차

To a stirred solution of sodium acetate trihydrate (22.62 g, 166.2 mmol) in water (80 ml) was added 1,1-dibromo-3,3,3-trifluoroacetone (21.57 g, 79.9 mmol). The solution was heated at reflux under nitrogen for 30 min, then allowed to cool to room temperature before adding solid aminoguanidine bicarbonate (10.88 g, 79.9 mmol). The resulting pale yellow solution (pH 5) was stirred at room temperature for 3 h, then 4 N aqueous NaOH solution (40 ml, 160 mmol) was added causing a precipitate to appear. The mixture (pH 10) was stirred under nitrogen for a further 39 h. The solid was collected by filtration, washed with water and dried at 60° C. under vacuum to give 6.96 g of a mixture of two isomers in a 28:72 ratio. This was further purified by flash chromatography (silica gel, 30% EtOAc/isohexane), then recrystallised from ethanol to afford 3.53 g (27%) of the title compound: 1H NMR (400 MHz, DMSO-d6) δ 8.00 (2H, br s), 9.08 (1H, s).

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