반응 #45614

반응 방정식

tributyl(1-ethoxyvinyl)tin

6-Bromo-2-cyclopropyl-7-fluoro-5-methyl-1,3-benzoxazole-4-carbonitrile

→

crude product

수율 108.5%

2-Cyclopropyl-6-[1-(ethoxy)ethenyl]-7-fluoro-5-methyl-1,3-benzoxazole-4-carbonitrile

수율 108.5%

용매

toluene

반응 조건

후처리

1. 1
   온도by heating
2. 2
   온도under reflux for 17 hours under nitrogen atmosphere
3. 3
   기타The reaction liquid
4. 4
   온도was cooled
5. 5
   기타the insoluble matter was separated by filtration through Celite
6. 6
   농축the solvent was concentrated under reduced pressure
7. 7
   기타by removing tin-
8. 8
   세척by elution with a mixed solvent of n-hexane/ethyl acetate (7:1

실험 절차

6-Bromo-2-cyclopropyl-7-fluoro-5-methyl-1,3-benzoxazole-4-carbonitrile (I-77) (8.88 g, 30.08 mmol) was dissolved in toluene (130 ml), then tributyl(1-ethoxyvinyl)tin (11.2 ml, 33.09 mmol) and 2,6-di-tert-butylcresol (66 mg, 0.30 mmol) and bis(triphenylphosphine)palladium(II) dichloride (1.06 g, 1.50 mmol) were added, followed by heating under reflux for 17 hours under nitrogen atmosphere. The reaction liquid was cooled, the insoluble matter was separated by filtration through Celite, the solvent was concentrated under reduced pressure. The resulting residue was subjected to silica gel column chromatography, followed by removing tin-derived side products with n-hexane and by elution with a mixed solvent of n-hexane/ethyl acetate (7:1, v/v) to obtain the a crude product (9.34 g, quant.) as a yellow white solid.

출처