反应详情

Potassium bis(trimethylsilyl)amide (a 0.5M solution in toluene; 6 ml, 3.02 mmol) was added dropwise to a solution of dodecyltriphenylphosphonium bromide (761 mg, 1.49 mmol) in tetrahydrofuran (10 ml) at -78° under argon. After 2 hours, a solution of bromine (81 μl , 1.49 mmol) in tetrahydrofuran (1 ml) was added. followed by a solution of 5-trimethylsilyl-3-furaldehyde (250 mg, 1.49 mmol) in tetrahydrofuran (1 ml) after 1 hour. Stirring was continued at room temperature for 2 days and the mixture was poured into methanol/water (30 ml, 1:1). Extraction (ethyl ether/hexane, 1:1) and evaporation of the dried extracts (magnesium sulphate) gave an oil which was chromatographed on silica using 10% ethyl ether/hexane. Fractions with Rf of about 0.71 on evaporation afforded the title alkene as a pale yellow oil.

1. waitwas continued at room temperature for 2 days
2. extractionExtraction (ethyl ether/hexane, 1:1) and evaporation of the dried extracts (magnesium sulphate)
3. customgave an oil which
4. customwas chromatographed on silica using 10% ethyl ether/hexane
5. customFractions with Rf of about 0.71 on evaporation