Реакция #6616

Уравнение реакции

hydroxy acetylene

1-((trimethylsilyl)ethynyl)-2-(4-fluoro-3-methylphenyl)-4,4,6,6-tetramethyl-cyclohexan-1-ol

Burgess reagent

→

1-((trimethylsilyl)ethynyl)-2-(4-fluoro-3-methylphenyl)-4,4,6,6-tetramethylcyclohexene

Выход 67.0%

Растворители

H2O

acetonitrile

Условия реакции

Обработка

1. 1
   ТемператураThe reaction mixture is heated
2. 2
   Температураat reflux for 14 hours
3. 3
   ЭкстракцияThe aqueous solution is extracted with ether
4. 4
   Промывкаthe combined ether layers are washed with H2O
5. 5
   СушкаThe ether fraction is dried over MgSO4
6. 6
   Другоеthe solvent is removed under reduced pressure
7. 7
   ДругоеPurification by silica gel chromatography (100% hexane)

Методика

To a solution of the hydroxy acetylene from Example 1, Step C above (20 g, 55.5 mmol) in acetonitrile (250 ml) is added 20 g (83 mmol) of Burgess reagent. The reaction mixture is heated at reflux for 14 hours, cooled to room temperature and diluted with H2O (1 L). The aqueous solution is extracted with ether and the combined ether layers are washed with H2O. The ether fraction is dried over MgSO4 and the solvent is removed under reduced pressure. Purification by silica gel chromatography (100% hexane) provides 12.7 g (67%) of 1-((trimethylsilyl)ethynyl)-2-(4-fluoro-3-methylphenyl)-4,4,6,6-tetramethylcyclohexene as an oil: 1H NMR δ=0.0 (s,9), 0.95 (s,6), 1.15 (s,6), 1.4 ((s,2), 2.1 (s,2), 2.2 (s,3), 6.85 (t,1), 7.25 (m,2).

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