Реакция #40545

Уравнение реакции

1-dimethylamino-4,4-dimethoxypent-1-en-3-one

N-ethylguanidine hydrochloride

sodium ethoxide

→

1-(2-Ethylaminopyrimidin-4-yl)ethanone

Условия реакции

Обработка

1. 1
   Температураis heated
2. 2
   Температураunder reflux for 2 hours
3. 3
   ТемператураAfter cooling
4. 4
   Фильтрацияthe solid is filtered off with suction
5. 5
   Концентрированиеthe filtrate is concentrated in vacuo
6. 6
   workup.ADDITIONmixed with 20 ml of trifluoroacetic acid and 2 ml of water
7. 7
   workup.ADDITIONThen 50 ml of water are added
8. 8
   Экстракцияthe mixture is extracted twice with 25 ml of ethyl acetate each time
9. 9
   СушкаThe organic phase is dried over sodium sulfate
10. 10
    Концентрированиеconcentrated
11. 11
    ДругоеThe resulting oily residue is purified by column chromatography (silica gel, mobile phase: methylene chloride:methanol=98:2)

Методика

A mixture of 6 g of 1-dimethylamino-4,4-dimethoxypent-1-en-3-one, 3.96 g of N-ethylguanidine hydrochloride and 26 ml of 20% strength ethanolic sodium ethoxide solution is heated under reflux for 2 hours. After cooling, the solid is filtered off with suction, and the filtrate is concentrated in vacuo and mixed with 20 ml of trifluoroacetic acid and 2 ml of water and stirred at room temperature overnight. Then 50 ml of water are added, the pH is adjusted to 10 with sodium carbonate, and the mixture is extracted twice with 25 ml of ethyl acetate each time. The organic phase is dried over sodium sulfate and concentrated. The resulting oily residue is purified by column chromatography (silica gel, mobile phase: methylene chloride:methanol=98:2).

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