Formaldehyde → 4-(2-Hydroxyethyl)-4-phenylisochroman

Temperature

50 °C

In trifluoroacetic acid (50 ml) was dissolved 2,2-diphenyl-1,4-butanediol (5 g) followed by addition of paraformaldehyde (1.7 g) and the mixture was heated and stirred at 50° C. for 2 hours. The reaction mixture was then concentrated under reduced pressure and the residue was dissolved in ethyl acetate, washed with saturated aqueous sodium hydrogen carbonate solution and concentrated under reduced pressure. The residue was dissolved in ethanol (100 ml) followed by addition of sodium hydroxide (4 g) and water (50 ml) and the mixture was stirred at room temperature for 1 hour. After concentration under reduced pressure, the residue was dissolved in ethyl acetate, washed with water, dried and concentrated under reduced pressure. The residue was purified by silica gel column chromatography using isopropyl ether/ethyl acetate as the eluent to provide 4-(2-hydroxyethyl)-4-phenylisochroman (4.5 g).

1. temperaturethe mixture was heated
2. concentrationThe reaction mixture was then concentrated under reduced pressure
3. dissolutionthe residue was dissolved in ethyl acetate
4. washwashed with saturated aqueous sodium hydrogen carbonate solution
5. concentrationconcentrated under reduced pressure
6. dissolutionThe residue was dissolved in ethanol (100 ml)
7. additionfollowed by addition of sodium hydroxide (4 g) and water (50 ml)
8. stirringthe mixture was stirred at room temperature for 1 hour
9. concentrationAfter concentration under reduced pressure
10. dissolutionthe residue was dissolved in ethyl acetate
11. washwashed with water
12. customdried
13. concentrationconcentrated under reduced pressure
14. customThe residue was purified by silica gel column chromatography

ORD record

ord-e1e5a71ff7584168915d4956fd6c84ef

Source dataset

uspto-grants-1997_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05607939