反応 #1552080
ord-1e1f85c8ce9a43519d62d14f2abf8660
反応方程式
反応物
試薬
反応条件
後処理
- 1workup.ADDITIONwas added over 30 min while the temperature
- 2その他was kept below 5°
- 3その他to return to room temperature
- 4workup.STIRRINGAfter 2 h stirring
- 5その他The phases were separated
- 6抽出the aqueous one extracted twice with hexane
- 7洗浄The combined organic layers were washed with water, twice with 2M HCl and again with water
- 8乾燥dried (Na2SO4)
- 9その他the solvent removed in vacuo
- 10workup.DISSOLUTIONThe crude oil (5.7 g) was dissolved in methylene chloride (50 ml)
- 11その他The mild exothermic effect was controlled with a cool water bath
- 12その他had been completely consumed (30 min)
- 13workup.ADDITION2M NaOH was added
- 14workup.STIRRINGthe mixture stirred until it
- 15その他The phases were separated
- 16抽出the upper aqueous layer extracted twice with methylene chloride
- 17洗浄The combined organic layers were washed twice with 2M NaOH and water
- 18乾燥dried (MgSO4)
- 19その他evaporated in vacuo
実験手順
Diiodomethane (9.6 g, 36 mmol) was added at room temperature, with stirring and under nitrogen, to a solution of 1-(4-Isobutyl-6-methylcyclohex-3-enyl)ethanol 4b (3.5 g, 18 mmol) in hexane (50 ml). After cooling to 5° C. triethylaluminium (1M, 36 ml, 36 mmol) was added over 30 min while the temperature was kept below 5°. The reaction was allowed to return to room temperature and stirred for 16 h, then another portion of diiodomethane (9.6 g, 36 mmol) and triethylaluminium (1M, 36 ml, 36 mmol) were added. After a further 15 h yet more diiodomethane (4.8 g, 18 mmol) and triethylaluminium (1M, 18 ml, 18 mmol) were added. After 2 h stirring, the reaction being still incomplete, the reaction mixture was poured slowly, onto a stirred mixture of ice and water. The phases were separated and the aqueous one extracted twice with hexane. The combined organic layers were washed with water, twice with 2M HCl and again with water, dried (Na2SO4) and the solvent removed in vacuo. The crude oil (5.7 g) was dissolved in methylene chloride (50 ml) and solid 3-chloroperbenzoic acid (ca. 77%, 1.5 g, 6.7 mmol) was added in four portions under nitrogen. The mild exothermic effect was controlled with a cool water bath. The reaction was stirred till the unreacted 4b had been completely consumed (30 min). 2M NaOH was added and the mixture stirred until it became white. The phases were separated and the upper aqueous layer extracted twice with methylene chloride. The combined organic layers were washed twice with 2M NaOH and water, dried (MgSO4) and evaporated in vacuo to give 4.6 g of oil. The crude oil was purified by flash chromatography (MTBE/hex. 3:2) and combination of pure fractions gave 5b as a 1:1.1:1.8 mixture of diastereomers (3.4 g, 86% yield, colourless oil, 95% pure). Subsequent distillation provided an olfactory pure sample.