Preparation of 3,6-Disubstituted Pyridazines from 3-Thiapentane-1,5-diones via 2,7-Dihydro-1,4,5-thiadiazepines
作者:Juzo Nakayama、Toru Konishi、Akihiko Ishii、Masamatsu Hoshino
DOI:10.1246/bcsj.62.2608
日期:1989.8
diethylene glycol affords the corresponding pyridazines in high yields with evolution of hydrogen sulfide. The above procedure is generally applicable to the preparation of a wide variety of 3,6-disubstituted pyridazines which are of structural interest and otherwise difficult to prepare.
一系列 3-thiapentane-1,5-diones 与肼在催化量的对甲苯磺酸存在下在回流乙醇中缩合,以极好的收率得到 2,7-dihydro-1,4,5-thiadiazepines。后一种化合物在回流的二甘醇中热分解以高产率提供相应的哒嗪,并放出硫化氢。上述程序通常适用于制备各种具有结构意义且难以制备的 3,6-二取代哒嗪。