(CAS NO.: ), which is also known as Ketone, dicyclopropyl, could be produced through the following synthetic routes.

A solution of sodium methoxide is prepared from 50 g. (2.17 g. atoms) of freshly cut sodium and 600 ml. of absolute methanol in a 3-l. three-necked flask placed on a steam bath and equipped with a sealed stirrer, dropping funnel, and a condenser set downward for distillation. To the stirred solution is added in one portion 344 g. (4.0 moles) of γ-butyrolactone, and the flask is heated until methanol distils at a rapid rate. After 475 ml. of methanol is collected, a filter flask or other suitable device equipped with a side arm is connected to the condenser. This receiver is surrounded by an ice bath, and reduced pressure from an aspirator is applied cautiously (frothing) with continuous stirring. An additional 50–70 ml. of methanol is collected in this way. The residue presumably is dibutyrolactone.

The condenser is set for reflux, and the steam bath is replaced with a more potent source of heat (electric heating mantle, oil bath, or direct flame). Concentrated hydrochloric acid is added with stirring, cautiously at first because a considerable amount of carbon dioxide is evolved. A total of 800 ml. of acid is added in about 10 minutes. The mixture is heated under reflux with stirring for 20 minutes, then cooled in an ice bath. A solution of 480 g. of sodium hydroxide in 600 ml. of water is added to the stirred mixture as rapidly as possible, without allowing the temperature to go above 50°. The mixture is then heated under reflux for an additional 30 minutes.

The condenser is arranged for downward distillation, and a total of 650 ml. of ketone-water mixture is collected as distillate. Sufficient potassium carbonate is added to saturate the aqueous layer, and about 130 ml. of ketone is separated. The aqueous layer is extracted with three 100-ml. portions of ether, and the combined ether and ketone layers are dried over 25 g. of anhydrous magnesium sulfate. The product remaining after removal of the ether is distilled through an efficient column. The yield of dicyclopropyl ketone boiling at 72–74°/33 mm., n_D25 1.4654, is 114–121 g. (52–55%).