반응 #45633

반응 방정식

trimethylsilyldiazomethane

7-Fluoro-2-(2-hydroxy-1,1-dimethylethyl)-5-methyl-6-phenyl-1,3-benzoxazole-4-carbonitrile

tetrafluoroboric acid

water

trimethylsilyldiazomethane

→

compound

수율 79.0%

7-Fluoro-2-(2-methoxy-1,1-dimethylethyl)-5-methyl-6-phenyl-1,3-benzoxazole-4-carbonitrile

수율 79.0%

용매

methylene chloride

반응 조건

후처리

1. 1
   workup.ADDITIONwas dropwise added
2. 2
   workup.STIRRINGby stirring at 0° C. for 1 hour
3. 3
   workup.ADDITIONwas added
4. 4
   추출followed by extraction with methylene
5. 5
   세척washing with saturated brine
6. 6
   건조The obtained organic layer was dried over anhydrous sodium sulfate
7. 7
   기타the solvent was evaporated away under reduced pressure
8. 8
   세척eluted with n-hexane/ethyl acetate (5:1

실험 절차

7-Fluoro-2-(2-hydroxy-1,1-dimethylethyl)-5-methyl-6-phenyl-1,3-benzoxazole-4-carbonitrile (I-99) (50 mg, 0.15 mmol) was dissolved in methylene chloride (0.5 ml), aqueous 42% tetrafluoroboric acid solution (32 μl, 0.15 mmol) was added, then with cooling with ice, trimethylsilyldiazomethane (2 M hexane solution, 77 μl, 0.15 mmol) was dropwise added, followed by stirring at 0° C. for 10 minutes, further trimethylsilyldiazomethane (2 M, hexane solution, 77 μl, 0.15 mmol) was dropwise added, followed by stirring at 0° C. for 1 hour. After the reaction, water was added followed by extraction with methylene and washing with saturated brine. The obtained organic layer was dried over anhydrous sodium sulfate, the solvent was evaporated away under reduced pressure. The resulting residue was subjected to preparative thin-layer silica gel column chromatography, eluted with n-hexane/ethyl acetate (5:1, v/v) to obtain the entitled compound (41.2 mg, 79%) as a colorless transparent oily substance.

출처