Phenol → 3-(4-hydroxyphenyl)butanoic acid

Temperature

70 °C

A solution of compound 23.7 (0.3 g, 0.457 mmol) and benzyl bromide (0.165 mL, 1.39 mmol) in THF (10 mL) was treated with potassium tert-butoxide (1M/THF, 1.2 mL) for 0.5 h. The mixture was diluted with ethylacetate and washed with HCl (0.2N). The organic phase was dried over magnesium sulfate, filtered and concentrated under reduced pressure. The residue was dissolved in ethyl acetate and treated with 10% Pd/C (0.05 g) under hydrogen atmosphere (balloon) for 16 h. The catalyst was removed by filtration and the filtrate was concentrated under reduced pressure. The residue was treated with TFA (1 mL) in methanol (5 mL) for 1 h, and then concentrated under reduced pressure. The residue was dissolved in pyridine (1 mL) and mixed with phenol (0.45 g, 4.8 mmol) and 1,3-dicyclohexylcarbodiimide (0.38 g, 1.85 mmol). The mixture was stirred at 70° C. for 2 h, and then concentrated under reduced pressure. The residue was partitioned between ethyl acetate and HCl (0.2N). The organic phase was dried over magnesium sulfate, filtered and concentrated. The residue was purified by chromatography on silica gel to afford compound 23.8 (0.085 g, 24%).

1. washwashed with HCl (0.2N)
2. dry with materialThe organic phase was dried over magnesium sulfate
3. filtrationfiltered
4. concentrationconcentrated under reduced pressure
5. dissolutionThe residue was dissolved in ethyl acetate
6. additiontreated with 10% Pd/C (0.05 g) under hydrogen atmosphere (balloon) for 16 h
7. customThe catalyst was removed by filtration
8. concentrationthe filtrate was concentrated under reduced pressure
9. additionThe residue was treated with TFA (1 mL) in methanol (5 mL) for 1 h
10. concentrationconcentrated under reduced pressure
11. dissolutionThe residue was dissolved in pyridine (1 mL)
12. concentrationconcentrated under reduced pressure
13. customThe residue was partitioned between ethyl acetate and HCl (0.2N)
14. dry with materialThe organic phase was dried over magnesium sulfate
15. filtrationfiltered
16. concentrationconcentrated
17. customThe residue was purified by chromatography on silica gel

ORD record

ord-4fa61adf1092494f954a8806e40c0aa1

Source dataset

uspto-grants-2010_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07649015B2