4,4'-Dihydroxybiphenyl → HCID 88020563, compound

Temperature

100 °C

A solution of 28.7 g (0.15 mol) of 4,4′-bisphenol in 75 mL of DMSO was placed into a 500 mL round-bottom flask. The solution was purged with nitrogen gas at room temperature (23° C.) for 2-3 hours. Then, 140.85 niL of 2.13M (0.300 mol) of standardized aq KOH was added dropwise to the solution in the flask, while the flask rested in an ice-bath and the nitrogen gas purge continued. After the KOH solution was added, the reaction mixture was heated to 100° C. and stirred for 1 day, followed by distilling off most of the water. The remaining solvent was evaporated off slowly under reduced pressure (10 torr). The reaction product was then dried thoroughly at 140-150° C. with full vacuum (10−2 torr) for at least 2 days. Then, a solution of 104 g (0.4 mol) of 1,2-dibromotetrafluoroethane in 100 mL of well-dried DMSO was transferred to the flask via a closed system. The mixture was stirred at 35-40° C. for 4 days, followed by filtration to remove the solid precipitate. The precipitate was washed with acetone three times. The combined acetone solution was then washed in a separatory funnel, first with a 5% sodium bicarbonate water solution, then with 0.1N HCl, and finally washed with distilled water and dried over sodium sulfate overnight. After removing solid material by filtration and evaporating the solvents at reduced pressure (10 torr), the crude product was purified by sublimation with an oil bath at a temperature around 100-110° C. A product of 75 g (0.137 mol) of 4,4-di(2-bromotetrafluoroethoxy)biphenyl was obtained at a yield of 91%. The amount of hydrogen by-product in the final product was around 1%.

1. customThe solution was purged with nitrogen gas at room temperature (23° C.) for 2-3 hours
2. customrested in an ice-bath
3. customthe nitrogen gas purge
4. additionAfter the KOH solution was added
5. distillationby distilling off most of the water
6. customThe remaining solvent was evaporated off slowly under reduced pressure (10 torr)
7. customThe reaction product was then dried thoroughly at 140-150° C. with full vacuum (10−2 torr) for at least 2 days
8. stirringThe mixture was stirred at 35-40° C. for 4 days
9. filtrationfollowed by filtration
10. customto remove the solid precipitate
11. washThe precipitate was washed with acetone three times
12. washThe combined acetone solution was then washed in a separatory funnel, first with a 5% sodium bicarbonate water solution
13. washwith 0.1N HCl, and finally washed with distilled water
14. dry with materialdried over sodium sulfate overnight
15. customAfter removing solid material
16. filtrationby filtration
17. customevaporating the solvents at reduced pressure (10 torr)
18. customthe crude product was purified by sublimation with an oil bath at a temperature around 100-110° C

ORD record

ord-fdcbbf1427554570bd28c53191e6104c

Source dataset

uspto-grants-2002_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06384167B2