アルキルケテンダイマーに関する研究 (第6報)

ジメチルホルムアミドおよびオキシ塩化リンを用いる脂肪酸クロリドの合成

抄録

Synthesis of fatty acid chlorides with dimethylformamide (I), phosphorous oxychloride (II) and fatty acids (III) such as palmitic, stearic and lauric acid were studied.
The reaction seems to contain two steps; at the beginning one mol of (III) reacts with one mol of (I) and (II) to form acid chloride and intermediate, then the intermediate combines another mol of (III) to produces another acid chloride.
The optimum conditions, considered economical, were about 0.5mol of (I) and 0.7mol of (II) to a mol of (III), the reaction temperature being a few degrees above the melting point of fatty acids with reaction time of one hour.
It is economically advantageous to use the lower layer produced at the end of the reaction for the next run.
The fatty acid chlorides produced by this procedure contain less than 1% of free fatty acids and very small quantity of phosphorous compounds. The quality of alkyl ketene dimer synthesized from fatty acid chloride produced by this procedure was identical to that from distilled fatty acid chloride.