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

Temperature

170 °C

The resulting reaction solution was stirred at 170° C. for 8 hours, and then cooled to 90° C. To this reaction solution was added dropwise 177.5 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 52.64 g (505.3 mmol) 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 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. After the crystals were washed with 20 g of toluene at 0° C., the crystals were air-dried to give 44.1 g of white crystals of 4′-methylbiphenyl-2-carboxylic acid (yield: 90.4% based on 2-cyano-4′-methylbiphenyl, purity: 99.9%). The resulting white crystals had a melting point of 150.1° 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. temperaturegradually cooled
10. customwas lowered to 0° C.
11. temperatureits temperature was maintained for one hour
12. filtrationthe crystals were filtered
13. washAfter the crystals were washed with 20 g of toluene at 0° C.
14. customthe crystals were air-dried

ORD record

ord-efd1a3035b42471dbb73c19701f0bf19

Source dataset

uspto-grants-2002_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06369266B1