Reaktion #45888

Reaktionsgleichung

hydrochloric acid

2-Cyclopropyl-7-fluoro-6-formyl-5-methyl-1,3-benzoxazole-4-carbonitrile

sodium dihydrogenphosphate dihydrate

2-methyl-2-butene

sodium chlorite

→

4-Cyano-2-cyclopropyl-7-fluoro-5-methyl-1,3-benzoxazole-6-carboxylic acid

Lösungsmittel

ethyl acetate

tert-butanol

water

tetrahydrofuran

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.STIRRINGby stirring at the same temperature for 10 minutes
2. 2
   SonstigeThe aqueous layer was separated
3. 3
   Extraktionextracted twice with ethyl acetate
4. 4
   Waschenwashed with saturated brine
5. 5
   Trocknendried over anhydrous sodium sulfate
6. 6
   SonstigeThe insoluble matter was separated by filtration
7. 7
   Sonstigethe solvent was evaporated away
8. 8
   Sonstigeto obtain the entitled compound
9. 9
   SonstigeThis was used in the next reaction as such

Vorschrift

2-Cyclopropyl-7-fluoro-6-formyl-5-methyl-1,3-benzoxazole-4-carbonitrile (I-182) (160 mg, 0.66 mmol) was dissolved in tert-butanol (4.5 ml)-water (3 ml)-tetrahydrofuran (3 ml), then at 0° C., sodium dihydrogenphosphate dihydrate (153 mg, 0.98 mmol), 2-methyl-2-butene (292 μl, 2.62 mmol), sodium chlorite (purity 80%, 222 mg, 1.97 mmol) were added. This was stirred for 15 hours with gradually warming up to room temperature. At 0° C., aqueous 1 N hydrochloric acid solution and ethyl acetate were added to the reaction liquid, followed by stirring at the same temperature for 10 minutes. The aqueous layer was separated, and extracted twice with ethyl acetate. The organic layers were combined, washed with saturated brine, and dried over anhydrous sodium sulfate. The insoluble matter was separated by filtration, the solvent was evaporated away to obtain the entitled compound. This was used in the next reaction as such.

Quelle