Реакция #10260

Уравнение реакции

Diisobutylaluminum hydride

ester

(3R,5R)-3,5-Bis[(tert-butyldimethylsilyl)oxy]-1-hydroxy-4-methylenecyclohexanecarboxylic Acid Methyl Ester

→

diol

Выход 24.0%

[(3R,5R)-3,5-Bis[(tert-butyldimethylsilyl)oxy]-1-hydroxy-4-methylenecyclohexyl]methanol

Выход 24.0%

Растворители

ether

ether

Условия реакции

Обработка

1. 1
   Другоеquenched by the slow addition of 2N potassium sodium tartrate
2. 2
   ТемператураThe solution was warmed to room temperature
3. 3
   workup.STIRRINGstirred for 15 min
4. 4
   workup.ADDITIONpoured into brine
5. 5
   Экстракцияextracted with ethyl acetate and ether
6. 6
   Промывкаwashed
7. 7
   workup.ADDITIONwith diluted (ca. 1%) HCl, and brine
8. 8
   Сушкаdried (MgSO4)
9. 9
   Другоеevaporated
10. 10
    ДругоеThe crystalline residue was purified by flash chromatography
11. 11
    ПромывкаElution with hexane/ethyl acetate (9:1)

Методика

Diisobutylaluminum hydride (1.5 M in toluene, 2.0 mL, 3 mmol) was added to a solution of the ester 3 (215 mg, 0.5 mmol) in anhydrous ether (3 mL) at −78° C. under argon. The mixture was stirred at −78° C. for 3 h and at −24° C. for 1.5 h, diluted with ether (10 mL) and quenched by the slow addition of 2N potassium sodium tartrate. The solution was warmed to room temperature and stirred for 15 min, then poured into brine and extracted with ethyl acetate and ether. The organic extracts were combined, washed with diluted (ca. 1%) HCl, and brine, dried (MgSO4) and evaporated. The crystalline residue was purified by flash chromatography. Elution with hexane/ethyl acetate (9:1) gave crystalline diol 4 (43 mg, 24%).

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