Reaktion #2289441

Reaktionsgleichung

Borane THF

trans-2-(ethoxycarbonyl)cyclopropanecarboxylic acid

tert-butylchlorodiphenylsilane

imidazole

→

ethyl trans-2-((tert-butyldiphenylsilyloxy)methyl)cyclopropanecarboxylate

Ausbeute 79.0%

Lösungsmittel

THF

water

MeOH

Reaktionsbedingungen

Aufarbeitung

1. 1
   EinengenThe reaction mixture was concentrated under reduced pressure
2. 2
   workup.DISSOLUTIONThe residue was dissolved in DMF (50 mL)
3. 3
   workup.STIRRINGthe mixture was stirred for 5 hr
4. 4
   Extraktionthe mixture was extracted with ethyl acetate
5. 5
   WaschenThe organic layer was washed with water and brine
6. 6
   Trocknendried over magnesium sulfate
7. 7
   Einengenconcentrated under reduced pressure
8. 8
   Sonstigethe obtained residue was purified by silica gel column chromatography (solvent gradient; 2→35% ethyl acetate/hexane)

Vorschrift

1M Borane-THF complex THF solution (85 mL, 84.98 mmol) was added to a solution of trans-2-(ethoxycarbonyl)cyclopropanecarboxylic acid (11.2 g, 70.82 mmol) in THF (100 mL) at 0° C., and the mixture was stirred overnight at room temperature. MeOH was added thereto, and then the gas was not generated. The reaction mixture was concentrated under reduced pressure. The residue was dissolved in DMF (50 mL), tert-butylchlorodiphenylsilane (20.10 mL, 84.98 mmol) and imidazole (5.79 g, 84.98 mmol) were added thereto, and the mixture was stirred for 5 hr. To the reaction mixture was added water, and the mixture was extracted with ethyl acetate. The organic layer was washed with water and brine, dried over magnesium sulfate, and concentrated under reduced pressure, and the obtained residue was purified by silica gel column chromatography (solvent gradient; 2→35% ethyl acetate/hexane) to give ethyl trans-2-((tert-butyldiphenylsilyloxy)methyl)cyclopropanecarboxylate (21.40 g, 55.9 mmol, 79%) as a colorless oil.

Quelle