반응 #6595

반응 방정식

sodium

allyl bromide

ethyl 4-cyclohexyloxy-acetoacetate

→

Ethyl 2-(cyclohexyloxyacetyl)-4-pentenoate

용매

ethanol

반응 조건

후처리

1. 1
   기타fitted with a stirrer
2. 2
   기타drying tube
3. 3
   온도reflux condenser
4. 4
   workup.ADDITIONis added at 50° C. in the course of 30 minutes
5. 5
   기타are then metered in at 50°-60° C. in the course of 30 minutes
6. 6
   온도while cooling
7. 7
   workup.DISTILLATIONthe ethanol is then distilled off
8. 8
   기타After the phases have been separated
9. 9
   추출the aqueous phase is extracted twice with 750 ml of toluene each time
10. 10
    농축concentrated
11. 11
    workup.DISTILLATIONthe residue is distilled

실험 절차

320 g of ethyl 4-cyclohexyloxy-acetoacetate (1.4 mol) are initially introduced into a threenecked flask fitted with a stirrer, dropping funnel, drying tube and reflux condenser, and an Na ethanolate solution prepared from 32 g of sodium (1.4 mol) and 475 g of ethanol is added at 50° C. in the course of 30 minutes. 170 g of allyl bromide (1.4 mol) are then metered in at 50°-60° C. in the course of 30 minutes, while cooling. The mixture is subsequently stirred at 50° C. for 2 hours, the ethanol is then distilled off and the reaction mixture which remains is brought to pH=3 with hydrochloric acid. After the phases have been separated, the aqueous phase is extracted twice with 750 ml of toluene each time, the organic phases are combined and concentrated and the residue is distilled. Ethyl 2-(cyclohexyloxyacetyl)-4-pentenoate is obtained. (Temperature (bottom)=152°-179° C., temperature (top)=102°-127° C.; 1 mbar).

출처