반응 #1156275

반응 방정식

Diisobutylaluminum hydride

methyl (R)-2-[tert-butyl(dimethyl)silyl]oxy-2-(3,5-dichlorophenyl)ethanoate

Rochelle's salt

→

(2R)-2-[tert-butyl(dimethyl)silyl]oxy-2-(3,5-dichlorophenyl)ethanal

수율 98.7%

용매

ethyl acetate

toluene

반응 조건

후처리

1. 1
   workup.ADDITIONwas added dropwise
2. 2
   여과The biphasic system was filtered through celite
3. 3
   세척rinsing with water and ethyl acetate
4. 4
   기타The filtrate was separated into its two layers
5. 5
   추출the aqueous layer was extracted with ethyl acetate
6. 6
   추출The extract
7. 7
   세척washed with saturated aqueous sodium chloride solution
8. 8
   건조dried (magnesium sulfate)
9. 9
   농축concentrated

실험 절차

Diisobutylaluminum hydride (56.5 mL, 1.5 M in toluene) was added dropwise over 1 h to a cooled (−78° C.) solution of methyl (R)-2-[tert-butyl(dimethyl)silyl]oxy-2-(3,5-dichlorophenyl)ethanoate (14.81 g) in toluene (150 mL) under nitrogen. The resulting colorless solution was stirred at this temperature for 1 h, before a saturated aqueous solution of Rochelle's salt (70 mL) was added dropwise. The resulting mixture was allowed to warm to room temperature, and was then diluted with ethyl acetate. The biphasic system was filtered through celite, rinsing with water and ethyl acetate . The filtrate was separated into its two layers, and the aqueous layer was extracted with ethyl acetate. The extract and the organic layer of the filtrate were combined, washed with saturated aqueous sodium chloride solution, dried (magnesium sulfate), and concentrated to afford (2R)-2-[tert-butyl(dimethyl)silyl]oxy-2-(3,5-dichlorophenyl)ethanal as a colorless oil (13.36 g). Based on its 1H-NMR spectrum, the title compound made up ca. 50% of the oil.

출처