Dimethyl Sulfoxide → 5-(2-Fluoro-6-methoxyphenyl)-1,3-oxazolidine-2,4-dione

HRID 434839Notes

Reaction equation

HRID 434839 reaction equation
F[C:2]1[CH:7]=[CH:6][CH:5]=[C:4]([F:8])[C:3]=1[CH:9]1[O:13][C:12](=[O:14])[NH:11][C:10]1=[O:15].CS(C)=O.C[C:21](C)([O-:23])C.[K+]>CO>[F:8][C:4]1[CH:5]=[CH:6][CH:7]=[C:2]([O:23][CH3:21])[C:3]=1[CH:9]1[O:13][C:12](=[O:14])[NH:11][C:10]1=[O:15]

Participants

5

Reactant 3

HCID 679Dimethyl SulfoxideHCID 13092030HCID 13092030, compoundHCID 23665647Potassium tert-butoxide

Product 1

HCID 130920335-(2-Fluoro-6-methoxyphenyl)-1,3-oxazolidine-2,4-dione

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Conditions

Temperature
155 °C

Procedure

5-(2,6-Difluorophenyl)oxazolidine-2,4-dione (2.0 g., 9.4 mmoles) was dissolved in 50 ml. of dimethylsulfoxide. Methanol (5 ml.) and then potassium tert-butoxide (2.11 g., 18.8 mmoles) were then added and the reaction mixture heated in an oil bath maintained at 155° C. for 4 hours. The reaction mixture was cooled to room temperature, poured into 200 ml. of 1 N hydrochloric acid and extracted with three portions of ethyl acetate. The combined organic extracts were washed with water and then brine, dried over anhydrous magnesium sulfate, filtered and concentrated to solids. The solids were taken up in 1 N sodium hydroxide, and the solution washed with three portions of ethyl acetate and then acidified with 1 N hydrochloric acid to precipitate purified 5-(2-fluoro-6-methoxyphenyl)oxazolidine-2,4-dione (1.32 g., 62%; m.p. 138°-142° C.). For analysis, the product was recrystallized from toluene (930 mg. recovered; m.p. 139°-141° C.).

Workup

  1. temperaturethe reaction mixture heated in an oil bath
  2. temperatureThe reaction mixture was cooled to room temperature
  3. additionpoured into 200 ml
  4. extractionof 1 N hydrochloric acid and extracted with three portions of ethyl acetate
  5. washThe combined organic extracts were washed with water
  6. dry with materialbrine, dried over anhydrous magnesium sulfate
  7. filtrationfiltered
  8. concentrationconcentrated to solids
  9. washthe solution washed with three portions of ethyl acetate
  10. customto precipitate
  11. custompurified 5-(2-fluoro-6-methoxyphenyl)oxazolidine-2,4-dione (1.32 g., 62%; m.p. 138°-142° C.)
  12. customFor analysis, the product was recrystallized from toluene (930 mg. recovered; m.p. 139°-141° C.)

Sources & evidence

ORD record
ord-f0da312f6b404f5cb9a3abffb46d04df
Source dataset
uspto-grants-1983_08
Patent number
US04399296

Reaction notes

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