تفاعل #46986

معادلة التفاعل

hydrochloric acid

4-propionyltetrahydropyran

dimethyl carbonate

sodium methoxide

→

methyl 3-(4-tetrahydropyranyl)-2-methyl-3-oxopropanoate

المردود 33.3%

المذيبات

water

ethyl acetate

ظروف التفاعل

المعالجة

1. 1
   أخرىIn a flask made of glass
2. 2
   أخرىequipped with a stirring device
3. 3
   أخرىthe mixture was reacted at 80 to 85° C. for 2 hours
4. 4
   workup.DISTILLATIONwith distilling
5. 5
   أخرىby-producing methanol off
6. 6
   أخرىAfter completion of the reaction
7. 7
   أخرىAfter the organic layer was separated
8. 8
   استخلاصthe aqueous layer was extracted twice with 50 ml of ethyl acetate
9. 9
   تركيزThe organic layer was concentrated under reduced pressure
10. 10
    أخرىthe concentrate was purified by silica gel column chromatography (Eluent; hexane/ethyl acetate=3/1 (volume ratio))

الإجراء التجريبي

In a flask made of glass having an inner volume of 100 ml and equipped with a stirring device, a thermometer, a dropping funnel and a distillation device were charged 1.28 g (9 mmol) of 4-propionyltetrahydropyran synthesized in the same manner as in Example 5, 16.0 g (180 mmol) of dimethyl carbonate and 1.2 g (22 mmol) of sodium methoxide, and the mixture was reacted at 80 to 85° C. for 2 hours with distilling by-producing methanol off. After completion of the reaction, the reaction mixture was cooled to 5 to 10° C., to the reaction mixture were added 50 ml of ethyl acetate, 3.4 g (24 mmol) of 6 mol/l hydrochloric acid and 15 ml of water in this order. After the organic layer was separated, the aqueous layer was extracted twice with 50 ml of ethyl acetate. The organic layer was concentrated under reduced pressure, and the concentrate was purified by silica gel column chromatography (Eluent; hexane/ethyl acetate=3/1 (volume ratio)) to give 0.60 g (Isolation yield: 33%) of methyl 3-(4-tetrahydropyranyl)-2-methyl-3-oxopropanoate as a colorless liquid.

المصدر