Hydrochloric Acid → 2-(4-Methylphenyl)benzoic acid

Temperature

150 °C

The resulting reaction solution was stirred at a temperature of 150° C. for 8 hours at a pressure of 1 to 2 kgf/cm2, and then cooled to 90° C. To this reaction solution was added dropwise 28.99 g of water. After the completion of dropwise addition, the mixture was stirred for 30 minutes. To this mixture was added 66.6 g of toluene, and 34.4 g (0.33 mol) of 35% hydrochloric acid was further added dropwise. The temperature inside the flask was raised to 75° C. to dissolve the resulting product in toluene and form into two layers. After the solution was allowed to stand to separate into layers, the lower aqueous layer was removed therefrom. The toluene layer was dehydrated over anhydrous magnesium sulfate, and the solution was then gradually cooled to allow sedimentation of white crystals of 4′-methylbiphenyl-2-carboxylic acid. The temperature was lowered to 0° C., and its temperature was maintained for one hour, and then the crystals were filtered. The crystals were washed with 15 g of toluene at 0° C., and then air-dried to give 28.8 g of white crystals of 4′-methylbiphenyl-2-carboxylic acid (yield: 90.6% based on 2-cyano-4′-methylbiphenyl, purity: 99.9%). The resulting white crystals had a melting point of 150.2° C.

1. customThe resulting reaction solution
2. temperaturecooled to 90° C
3. additionAfter the completion of dropwise addition
4. stirringthe mixture was stirred for 30 minutes
5. additionwas further added dropwise
6. temperatureThe temperature inside the flask was raised to 75° C.
7. customto separate into layers
8. customthe lower aqueous layer was removed
9. temperaturethe solution was then gradually cooled
10. customwas lowered to 0° C.
11. temperatureits temperature was maintained for one hour
12. filtrationthe crystals were filtered
13. washThe crystals were washed with 15 g of toluene at 0° C.
14. customair-dried

ORD record

ord-7356945ed6424184b6ede5ec4b373b45

Source dataset

uspto-grants-2002_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06369266B1