芳酸及其衍生物的三氯甲基化反应的研究

首次报道了以四氯苯膦为转化剂或采用二氯苯膦与五氯化磷相结合, 将芳酸或芳酰氯转化为三氯甲基芳烃. 同时, 对影响反应的因素进行了研究, 发现连有推电子基的二氯苯膦有促进反应的作用, 而连有吸电子基团则减缓反应的进行, 而反应底物(芳酸或芳酰氯)的结构效应则相反: 连有吸电子基的芳酸有利于反应, 而连有推电子基团则减缓反应的进行. 此外, 发现反应中生成的苯膦酰二氯可作为催化剂重复使用, 并对转化反应的条件进行了改进与优化, 合成出9个三氯甲基芳烃, 其中2个是未见文献报道的新化合物.

Study on Trichloromethylation Reaction of Aromatic Compounds

Trichloromethylation reaction of aromatic carboxylic acids or aroylchlorides has been accom- plished by using tetrachlorophenylphosphine or dichlorophenylphosphine/phosphoric chloride as the trans- forming agent. The trichloromethylation reaction can be well controlled and the phenylphosphonic dichlo- ride produced in the process can be reclaimed for reuse. A series of trichloromethylated aromatics including two new compounds, such as 3-trichloromethylbromobenzene and 2-trichloromethylmethbenzenetoluene, have been synthesized. The influences and the mechanism of the reaction have also been studied. It was found that the reaction was accelerated obviously with the electron-pushing groups attached to dichloro- phenylphosphine and was decreased with the electron-withdrawing groups attached. On the other hand, the effects of substituents of the aromatic acids (or aroylchloride) on the reaction were opposed.