تفاعل #461467

معادلة التفاعل

5-(4-methoxy-2,5-dimethylphenoxy)-2,2-dimethylpentanoic acid, methyl ester

5-(4-Methoxy-2,5-dimethylphenoxy)-2,2-dimethyl-pentanoic acid, methyl ester

potassium hydroxide

→

title compound

المردود 86.3%

5-(4-Methoxy-2,5-dimethylphenoxy)-2,2-dimethylpentanoic acid

المردود 86.3%

المذيبات

methanol

ظروف التفاعل

المعالجة

1. 1
   درجة الحرارةat reflux for 18 hours overnight
2. 2
   أخرىThe methanol is removed on a rotary evaporator
3. 3
   workup.ADDITIONthe aqueous solution diluted with water
4. 4
   استخلاصAfter the aqueous solution is extracted with diethyl ether it
5. 5
   أخرىthe precipitate is isolated with diethyl ether
6. 6
   غسيلThe diethyl ether solution is washed with brine
7. 7
   تجفيفdried (magnesium sulfate)
8. 8
   أخرىevaporated
9. 9
   أخرىleaving a crystalline residue
10. 10
    أخرىRecrystallization from 50 mL of acetonitrile in the presence of charcoal

الإجراء التجريبي

A solution containing 11.8 g (40.1 mmol) of 5-(4-methoxy-2,5-dimethylphenoxy)-2,2-dimethylpentanoic acid, methyl ester (Example 1), 40 mL of 2N potassium hydroxide and 150 mL of methanol is stirred at reflux for 18 hours overnight. The methanol is removed on a rotary evaporator and the aqueous solution diluted with water. After the aqueous solution is extracted with diethyl ether it is acidified with excess 6N hydrochloric acid solution and the precipitate is isolated with diethyl ether. The diethyl ether solution is washed with brine, dried (magnesium sulfate) and evaporated leaving a crystalline residue. Recrystallization from 50 mL of acetonitrile in the presence of charcoal affords after refrigeration, 9.7 g of the title compound as colorless crystals; mp 85°-86° C.

المصدر