The use of a Mitsunobu reagent for the formation of heterocycles: a simple method for the preparation of 3-alkyl-5-aryl-1,3,4-oxadiazol-2(3H)-ones from carboxylic acids
作者:Osamu Sugimoto、Tomoyo Arakaki、Hiroka Kamio、Ken-ichi Tanji
DOI:10.1039/c4cc01971g
日期:——
The reaction of carboxylic acids with Mitsunobu reagents, prepared by the reaction of triphenylphosphine with dialkyl azodicarboxylates, followed by heating at 180-190 degrees C under solvent-free conditions, afforded 3-alkyl-5-aryl-1,3,4-oxadiazol-2(3H)-ones. This facile and convenient method readily provides the 1,3,4-oxadiazolone ring systems in good yields using a one-pot protocol starting from
通过三苯膦与偶氮二羧酸二烷基酯的反应制备羧酸,与Mitsunobu试剂反应,然后在无溶剂的条件下于180-190℃加热,得到3-烷基-5-芳基-1,3,4-恶二唑-2(3H)-一个 这种简便易行的方法可以使用一锅法从相应的羧酸开始轻松地以高收率提供1,3,4-恶二唑酮环系统。还证明了催化碱的存在有助于形成1,3,4-恶二唑-2(3H)-one的最终闭环。