Carbon Dioxide → Cholesta-1,5,7-trien-3-on-25-ol

Beteiligte Stoffe

Reaktionsschritte

A reaction vessel was charged with 125 ml of dry dimethylsulfoxide and 2.5 g of cholesta-1,4,6-trien-3-on-25-ol was suspended in the dimethylsulfoxide. The suspension was heated, and 10 ml of dry ether was added to the resulting milky suspension to obtain a transparent solution. The reaction vessel was filled with dry argon gas. Powdery potassium t-butoxide prepared from 1.25 g potassium and 50 ml of butanol was added at one time to the solution under ice cooling and with violent agitation. The reaction mixture liquid was violently agitated for 12 minutes and was then poured into ice water saturated with carbon dioxide gas, which was prepared by adding dry ice to water. The mixture was then extracted with 600 ml of ether cooled to 0° to 5° C. The extract was promptly washed with cooled water saturated with a large quantity of carbon dioxide until the washing liquid became neutral, and the ether was then distilled off to obtain crude cholesta-1,5,7-trien-3-on-25-ol.

Herkunft & Nachweise