An efficient domino protocol for the synthesis of 1,2,4-oxadiazole derivatives from readily available 1-(2-oxo-2-arylethyl)pyridin-1-iums and amidine hydrochlorides was developed. In this practical approach, N-acyl amidine precursors were formed firstly via a simple nucleophilic substitution, without the purification of N-acylamidine intermediates, and the following intramolecularly dehydrative cyclization gave 1,2,4-oxadiazole derivatives in the presence of I₂/K₂CO₃/DMSO, which exhibited excellent functional group tolerance and proceeded under simple experimental conditions.

中文翻译：

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使用 1-(2-oxo-2-arylethyl)pyridin-1-iums 和苯甲脒直接合成 3,5-二芳基-1,2,4-恶二唑

开发了一种用于从容易获得的 1-(2-oxo-2-arylethyl)pyridin-1-iums 和脒盐酸盐合成 1,2,4-恶二唑衍生物的有效多米诺协议。在该实用的方法，Ñ酰基脒前体通过简单的亲核取代首先形成，未经纯化Ñ -acylamidine中间体和分子内下列脱水闭环中的我的存在下，得到1,2,4-恶二唑衍生物₂ / K ₂ CO ₃ /DMSO 表现出优异的官能团耐受性并在简单的实验条件下进行。