tert-Butyl methyl ether → 3,3-Difluoro-3,4-dihydro-2h-thieno[3,4-b][1,4]-dioxepine

HRID 1794558Notes

Reaction equation

HRID 1794558 reaction equation
[F:1][C:2]1([F:18])[CH2:8][O:7][C:6]2=[C:9](C(O)=O)[S:10][C:11](C(O)=O)=[C:5]2[O:4][CH2:3]1.COC(C)(C)C>N1C2C(=CC=CC=2)C=CC=1.[Cr]([O-])([O-])=O.[Cu+2]>[F:18][C:2]1([F:1])[CH2:8][O:7][C:6]2=[CH:9][S:10][CH:11]=[C:5]2[O:4][CH2:3]1

Participants

5

Reactant 2

HCID 15413tert-Butyl methyl etherHCID 222221443,3-difluoro-3,4-dihydro-2H-thieno[3,4-b][1,4]-dioxepine-6,8-dicarboxylic acid

Product 1

HCID 222221473,3-Difluoro-3,4-dihydro-2h-thieno[3,4-b][1,4]-dioxepineYield 40%

Reagents, catalysts & solvents 2

HCID 178505374HCID 178505374, compoundCatalystHCID 7047QuinolineSolvent

Procedure

300 mg (1.07 mmol) of 3,3-difluoro-3,4-dihydro-2H-thieno[3,4-b][1,4]-dioxepine-6,8-dicarboxylic acid was heated at 175° C. with 77 mg of copper chromite in 3.0 mL of quinoline for 1.5 hours. After cooling and mixing with 35 mL of tert-butyl methyl ether, the resulting mixture was washed three times with 2N hydrochloric acid, then three times with deionized water, dried with anhydrous magnesium sulphate and finally evaporated to dryness yielding 138 mg of raw product. The raw product was purified by column chromatography using Kieselgel 60 and cyclohexane as eluant. 82 mg of 3,3-difluoro-3,4-dihydro-2H-thieno[3,4-b][1,4]-dioxepine (M3) was obtained corresponding to a yield of 40% with a melting point of 66–67° C., as characterized by:

Workup

  1. temperatureAfter cooling
  2. washthe resulting mixture was washed three times with 2N hydrochloric acid
  3. dry with materialthree times with deionized water, dried with anhydrous magnesium sulphate
  4. customfinally evaporated to dryness
  5. customyielding 138 mg of raw product
  6. customThe raw product was purified by column chromatography

Sources & evidence

ORD record
ord-4273ca3bb90e4b318f48b7e935190d9f
Source dataset
uspto-grants-2006_04
Patent number
US07022811B2

Reaction notes

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