反応 #10260

反応方程式

Diisobutylaluminum hydride

ester

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

→

diol

収率 24.0%

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

収率 24.0%

溶媒

ether

ether

反応条件

後処理

1. 1
   その他quenched by the slow addition of 2N potassium sodium tartrate
2. 2
   温度The solution was warmed to room temperature
3. 3
   workup.STIRRINGstirred for 15 min
4. 4
   workup.ADDITIONpoured into brine
5. 5
   抽出extracted with ethyl acetate and ether
6. 6
   洗浄washed
7. 7
   workup.ADDITIONwith diluted (ca. 1%) HCl, and brine
8. 8
   乾燥dried (MgSO4)
9. 9
   その他evaporated
10. 10
    その他The crystalline residue was purified by flash chromatography
11. 11
    洗浄Elution with hexane/ethyl acetate (9:1)

実験手順

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%).

出典