반응 #2122483

반응 방정식

(2,4,5-trimethyl-phenyl)acetic acid methyl ester

4-hydroxy-1-methoxy-piperidine-4-carboxylic acid ethyl ester

potassium tert-butoxide

→

4-Hydroxy-8-methoxy-3-(2,4,5-trimethyl-phenyl)-1-oxa-8-aza-spiro[4.5]dec-3-en-2-one

용매

THF

THF

반응 조건

후처리

1. 1
   기타The suspension obtained
2. 2
   온도refluxed under argon for one hour
3. 3
   온도After cooling to room temperature
4. 4
   농축the reaction mixture was concentrated
5. 5
   workup.ADDITIONwater was added
6. 6
   추출The aqueous layer was extracted with dichloromethane
7. 7
   세척the combined organic layers were then washed with brine
8. 8
   건조dried over sodium sulfate
9. 9
   여과After filtration and concentration under vacuum
10. 10
    기타the residue was purified by column chromatography (silica gel, ethyl acetate 100%)

실험 절차

To a solution of (2,4,5-trimethyl-phenyl)acetic acid methyl ester (0.6 g, 3.12 mmol) and 4-hydroxy-1-methoxy-piperidine-4-carboxylic acid ethyl ester (0.76 g, 3.74 mmol) in 7 ml anhydrous THF was added a 1 M solution of potassium tert-butoxide (6.9 ml, 8.87 mmol) in THF at room temperature. The suspension obtained was first stirred at room temperature for one hour, and then refluxed under argon for one hour. After cooling to room temperature, the reaction mixture was concentrated, water was added and the mixture acidified with little HCl (37%). The aqueous layer was extracted with dichloromethane, and the combined organic layers were then washed with brine and dried over sodium sulfate. After filtration and concentration under vacuum, the residue was purified by column chromatography (silica gel, ethyl acetate 100%). Yield: 280 mg of 4-hydroxy-8-methoxy-3-(2,4,5-trimethyl-phenyl)-1-oxa-8-aza-spiro[4.5]dec-3-en-2-one (title compound P2.2) as a white solid, mp 199-204° C.

출처