3-Thietanone

Step 1: 3,3-Dimethoxythiocyclic butanone

Sodium sulfide (66.8 g, 506 mmol) was added to a solution of 1,3-dibromo-2,2-dimethoxypropane (102 g, 389 mmol) in N,N-dimethylformamide (1200 mL), and the mixture was refluxed for 3 days. The mixture was cooled to room temperature, diluted with diethyl ether (1200 mL), washed with water (1200 mL) and brine (1200 mL), dried over sodium sulfate, and concentrated under vacuum to give the product, a pale yellow oil (yield 40 g, 77%).

Step 2: 3-Thiohexacyclobutanone Add 160 g of dioxane to a solution of 40 g (600 mmol) of 3,3-dimethoxythiohexacyclobutane in 2500 mL of dichloromethane. Reflux the mixture for 2 days, cool it to room temperature, filter it through a diatomaceous earth mat, and concentrate the filtrate under vacuum to obtain the desired product, 3-Thietanone.

3-Thiohexacyclic ketone can be used as a pharmaceutical synthesis intermediate. It can be prepared from 1,3-dibromo-2,2-dimethoxypropane as a reactant to produce 3,3-dimethoxythiohexacyclic ketone, which can then be further reacted to obtain the final product.