Dichloromethane → 3,3-Dimethyl-1,5-dioxaspiro[5.5]undecan-8-one

Participants

Reaction Steps

448.5 g 1,3-cyclohexanedione, 416 g 2,2-dimethyl-1,3-propanediol and 12 g p-toluenesulfonic acid were introduced into 3,000 ml methylene chloride and the mixture was heated under reflux for 24 hours using a water separator. When the reaction had ended the mixture was cooled to room temperature and 2,000 ml 32% sodium hydroxide solution were added. The phases were separated and the organic phase was washed first with sodium bicarbonate solution (44.4 g sodium bicarbonate solution/850 ml water) and then with 350 ml water. The organic phase was dried over sodium sulfate and the solvent was then evaporated in vacuo. 345 g (50% of theory) 3,3-dimethyl-1,5-dioxa-spiro[5.5]undecan-8-one were obtained in this way.

Provenance & Evidence