Hydrochloric Acid → HCID 20318397, compound

Temperature

68 °C

11.8 grams of 5-tert.-butyl-2,3-dimethyl-4-hydroxyphenylacetic acid was added at 20° C to 200 ml of methanol previously saturated with hydrogen chloride gas. The slightly pinkish solution was heated at reflux (68° C) for 3 hours after which about one-half of the solvent was removed at reduced pressures and the reaction mixture then poured into about 500 ml of an ice-water mixture with stirring until all the ice had melted. The precipitated crystals were filtered, washed with water and dissolved in benzene. The benzene solution was successively washed with water, saturated sodium bicarbonate solution and finally with water to pH 7, the benzene solution being dried over anhydrous sodium sulfate. The clear benzene solution, freed of drying agent by filtration, was concentrated at reduced pressure. The resulting solid residue was triturated with hexane to remove color bodies. After recrystallization from methanol, the desired product was obtained as white crystals melting at 117° to 119° C (Compound 14).

1. temperatureThe slightly pinkish solution was heated
2. customwas removed at reduced pressures
3. additionthe reaction mixture then poured into about 500 ml of an ice-water mixture
4. filtrationThe precipitated crystals were filtered
5. washwashed with water
6. dissolutiondissolved in benzene
7. washThe benzene solution was successively washed with water, saturated sodium bicarbonate solution and finally with water to pH 7
8. dry with materialthe benzene solution being dried over anhydrous sodium sulfate
9. customof drying agent
10. filtrationby filtration
11. concentrationwas concentrated at reduced pressure
12. customThe resulting solid residue was triturated with hexane
13. customto remove color bodies
14. customAfter recrystallization from methanol

ORD record

ord-09d6fdd8bf2f4d04ab807013fda8353b

Source dataset

uspto-grants-1978_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04101550