Ethanol → Oct-2-ene

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To 5 ml of dioxane and 200 mg of a suspension of 55% w/w sodium hydride in mineral oil was added 1 ml of diethyl carbonate, and the mixture was heated, with stirring, at an external temperature of 90° C. To the mixture was then added dropwise a solution of 150 ml of 3-(5-benzyloxypentyl)-7-oxo-cis-bicyclo[3,3,0]oct-2-ene (prepared as described in Preparation 5) in 3 ml of dioxane. During this addition, a catalytic amount of ethanol was also added. The mixture was stirred for 1 hour at 0° C., after which it was poured into ice-water, acidified with acetic acid and then extracted with ethyl acetate: The extract was washed with a saturated aqueous solution of sodium chloride and dried over anhydrous sodium sulfate. The solvent was evaporated off under reduced pressure, and the resulting residue was purified by silica gel column chromatography. 72 mg of the oct-2-ene isomer of the title compound and 57 mg of the oct-3-ene isomer were obtained from the fractions eluted with hexane containing 3% by volume of ethyl acetate and 5% by volume of ethyl acetate, respectively.

Herkunft & Nachweise