N-芳基氮氧方酸的合成研究

Study on Synthesis of Monorylamide of Squar

N-芳基氮氧方酸(3-芳胺基-4-羟基-3-环丁烯二酮)是合成不对称方酸衍生物的关键中间体之一,开展了对其合成方法的研究,发现并实现了方酸与芳伯胺在水中的脱水反应,制得17个N-芳基氮氧方酸3a～3q,其中N-8’-喹啉基氮氧方酸(3q)具有热致变色性质,根据实验事实,提出了可能的反应历程。该合成方法产率较高,产物易于分离纯化,是制备N-芳基氮氧方酸简便有效的好方法。

N - Aryl substituted nitrogenoxosquaric acid ( 3 - arylamino - 4 - hydroxy - 3 - cy-clobutenedione) is one of the very important intermediates for the preparation of asymmetric squaric acid derivatives. The study on synthetic method of preparation of monoamide of squaric acid is carried out. Surprisingly,during the reaction between a little excess oxosquaric acid and primary arylamine in water,we observed dehydration and have performed it. Seventeen N - arylnitrogenoxosquaric acid 3a-3q have been successfully synthesized, of which 3q appears phenomenon of thermotrophic colour. A possible reaction mechanism is discussed in accordance with the facts of reactions. Highly yielding,easily separating and puring are the merits of this synthetic method.