تفاعل #461470

معادلة التفاعل

sodium phenolate

hydrogen

bromo-2,2 dimethylvaleric acid, methyl ester

2,5-dimethyl-4-(phenylmethoxy)-phenol

sodium hydride

→

dark brown oil

5-[2,5-Dimethyl-4-(phenylmethoxy)phenoxy]-2,2-dimethylpentanoic acid, methyl ester

المذيبات

toluene

water

toluene

dimethylsulfoxide

ظروف التفاعل

المعالجة

1. 1
   أخرىA 1 liter, 3 neck round bottom flask fitted with an overhead stirrer
2. 2
   workup.ADDITION4,665,226) is added
3. 3
   أخرىreaches 55° C.
4. 4
   درجة الحرارةAfter 18 hours overnight the mixture is heated
5. 5
   درجة الحرارةto reflux for 4 hours
6. 6
   درجة الحرارةthen the mixture is cooled
7. 7
   استخلاصThe aqueous layer is extracted with diethyl ether
8. 8
   غسيلthe solution is washed with water
9. 9
   تجفيفdried (magnesium sulfate)
10. 10
    أخرىevaporated

الإجراء التجريبي

A 1 liter, 3 neck round bottom flask fitted with an overhead stirrer is charged with 100 mL of dimethylsulfoxide and 6.0 g of 60% sodium hydride, washed free of mineral oil with toluene (3.6 g contained; 150 mmol), then a solution of 34.2 g 150 mmol) of 2,5-dimethyl-4-(phenylmethoxy)-phenol (Example K) in 200 mL of toluene is added at 20°-25° C. When hydrogen evolution is complete, 40.1 g (1.2×150 mmol) of 5 bromo-2,2 dimethylvaleric acid, methyl ester (U.S. Pat. No. 4,665,226) is added and the temperature is raised to 75° C. When the temperature reaches 55° C., a solid separates (sodium phenolate). After 18 hours overnight the mixture is heated to reflux for 4 hours; then the mixture is cooled and 200 mL of water is added. The aqueous layer is extracted with diethyl ether and the organic layers are combined and the solution is washed with water, dried (magnesium sulfate) and evaporated leaving 65.7 g of a dark brown oil which crystallizes on standing. Recrystallization from hexane in the presence of charcoal affords 39.5 g of the title compound; mp 75.5°-76.5° C.

المصدر