反应详情

A portion (˜40.4 mL) of the ethanol solution of cyclopropanecarboximidamide monohydrochloride as prepared in Example 1 was added to a portion (˜210 mL) of the solution of the sodium salt of ethyl 4,4-diethoxy-3-oxobutanoate as prepared in Example 2. The mixture was allowed to stir overnight at room temperature. The mixture was boiled for about 2 h and then allowed to cool to room temperature. The mixture was evaporated under reduced pressure, and the residue was redissolved in toluene (200 mL). A solution of ammonium chloride (0.68 g, 12.7 mmol) in water (30 mL) was added. After stirring for 10 minutes, the aqueous phase was removed. The organic phase was dried and evaporated to leave the product as pale yellow solid (27.27 g, 88% yield). Product recrystallized from hexanes melted at 111.5-112.0° C.

1. customas prepared in Example 2
2. waitThe mixture was boiled for about 2 h
3. temperatureto cool to room temperature
4. customThe mixture was evaporated under reduced pressure
5. dissolutionthe residue was redissolved in toluene (200 mL)
6. stirringAfter stirring for 10 minutes
7. customthe aqueous phase was removed
8. customThe organic phase was dried
9. customevaporated