作者:Michael A. Schmidt、Xinhua Qian
DOI:10.1016/j.tetlet.2013.08.024
日期:2013.10
The reaction between 2-hydrazinopyridines and ethyl imidates was examined as a one-pot method for rapidly preparing [1,2,4]triazolo[4,3-a]pyridines. A diverse set of 2-hydrazinopyridines were cyclized with a variety of alkyl- and aryl-substituted ethyl imidates in good yields. The reaction proceeds optimally under mild conditions (50−70 °C) using 1.5 equiv of acetic acid. The electronic and steric
作为快速制备[1,2,4]三唑并[4,3- a ]吡啶的一锅法,研究了2-肼基吡啶和酰亚胺乙酯之间的反应。用各种烷基取代基和芳基取代的乙基酰亚胺酯以高收率将各种不同的2-肼基吡啶环化。使用1.5当量的乙酸,在温和的条件下(50-70°C),反应可以最佳地进行。肼和亚氨酸酯的电子和位阻性质强烈影响反应速率。当使用高度缺乏电子的2-肼基吡啶时,产物重排为[1,2,4]三唑并[1,5- a ]吡啶。