Ethyl orthoformate → 3-Ethoxy-androsta-3,5-dien-17-one

Participants

Reaction Conditions

Reaction Steps

11α-Hydroxyandrostendione (429.5 g) and toluene sulfonic acid hydrate (7.1) were charged to a reaction flask under nitrogen. Ethanol (2.58 L) was added to the reactor, and the resulting solution cooled to 5° C. Triethyl orthoformate (334.5 g) was added to the solution over a 15 minute period at 0° to 15° C. After the triethyl orthoformate addition was complete the reaction mixture was warmed to 40° C. and reacted at that temperature for 2 hours, after which the temperature was increased to reflux and reaction continued under reflux for an additional 3 hours. The reaction mixture was cooled under vacuum and the solvent removed under vacuum to yield 3-ethoxyandrosta-3,5-diene-17-one.

Provenance & Evidence