ケテンとホルムアルデヒドの反応

β-プロピオラトクンの合成に関する研究 (第1報)

抄録

The synthesis of β-propiolactone by the reaction of ketene with formaldehyde was studied. When equimolar amounts of both gaseous starting materials were fed, higher yields of β-propiolactone were obtained. In order to control the reaction conditions, the method of quantitative generation and the analysis of two gaseous starting materials were establishd. β-Propiolactone and acetone were used as the solvents. Anhydrous aluminium chloride containing small amounts of zinc chloride was found to be the best catalyst. This catalyst dissolved easily in acetone. It was confirmed that acetone in the solution changed with time at room temperature to give mesityl oxide, which deactivated the catalyst. This deactivation could be prevented by storing this solution below 0°C. The shorter average residence time of the catalyst gave better yields of β-propiolactone because of fast absorption and chemical reaction rates of two gaseous materials and of the deactivation of the catalyst. Rate-determining step of this reaction was considered to be chemical reaction, and not absorption. The optimum catalyst concentration for the main reaction was determined.