Hydrochloric Acid → 4-Ethynylphenol

Temperature

80 °C

32.4 g (0.2 mols) of p-acetoxystyrene was dissolved in 120 ml of butyl acetate. To the solution was then added 0.033 g of azobisisobutylonitrile (AIBN) with stirring in a stream of nitrogen at a temperature of 80° C. every 2.5 hours three times in all. Finally, the mixture was stirred for 5 hours to undergo polymerization reaction. The reaction solution was then poured into 1,200 ml of hexane to cause the precipitation of a white resin. The resin thus obtained was dried, and then dissolved in 150 ml of methanol. To the solution was then added a solution of 7.7 g (0.19 mols) of sodium hydroxide in 50 ml of water. The reaction solution was then heated under reflux for 3 hours to undergo hydrolysis. Thereafter, the reaction solution was diluted with 200 ml of water, and then neutralized with hydrochloric acid to cause the precipitation of a white resin. The resin thus obtained was collected by filtration, washed with water, and then dried. The resin thus obtained was dissolved in 200 ml of tetrahydrofuran, and then added dropwise to 5 l of ultrapure water with vigorous stirring to cause reprecipitation. This reprecipitation procedure was then repeated three times. The resin thus obtained was then dried at a temperature of 120° C. in a vacuum drier for 12 hours to obtain a poly(p-hydroxystyrene) type alkali-soluble resin R-1.

1. stirringFinally, the mixture was stirred for 5 hours
2. custompolymerization reaction
3. customthe precipitation of a white resin
4. customThe resin thus obtained
5. customwas dried
6. dissolutiondissolved in 150 ml of methanol
7. temperatureThe reaction solution was then heated
8. temperatureunder reflux for 3 hours
9. customhydrolysis
10. customthe precipitation of a white resin
11. customThe resin thus obtained
12. filtrationwas collected by filtration
13. washwashed with water
14. customdried
15. customThe resin thus obtained
16. stirringwith vigorous stirring
17. customreprecipitation
18. customThis reprecipitation procedure
19. customThe resin thus obtained
20. customwas then dried at a temperature of 120° C. in a vacuum drier for 12 hours

ORD record

ord-0f0a932e2eb44b4f9d9cdecf5bca6b1c

Source dataset

uspto-grants-2001_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06207343B1