Three-component microwave-assisted synthesis of 3,5-disubstituted pyrazolo[3,4-<i>d</i>]pyrimidin-4-ones
作者:Jia Hui Ng、Edward R. T. Tiekink、Anton V. Dolzhenko
DOI:10.1039/d2ra00980c
日期:——
A practical three-component method for the synthesis of pyrazolo[3,4-d]pyrimidin-4-ones was developed. The reaction was performed in a one-pot manner under controlled microwave irradiation using easily accessible methyl 5-aminopyrazole-4-carboxylates, trimethyl orthoformate, and primary amines. Under the optimized conditions, challenging substrates, such as N-1 unsubstituted 5-aminopyrazole-4-carboxylates
开发了一种实用的三组分合成吡唑并[3,4- d ]嘧啶-4-酮的方法。该反应在受控微波辐射下以一锅法进行,使用容易获得的5-氨基吡唑-4-甲酸甲酯、原甲酸三甲酯和伯胺。在优化的条件下,具有挑战性的底物,例如在3位上具有另一个取代的氨基的N-1未取代的5-氨基吡唑-4-羧酸酯,选择性地反应,得到5-取代的3-芳基氨基-1,5-二氢-4H-吡唑并[3,4- d ]嘧啶-4-酮。该反应耐受一系列伯胺,包括苯胺。所开发方案的优点包括反应时间短、罐装和分步经济以及方便的免色谱产品分离。通过X射线晶体学探讨了代表性产物的结构特征。