Modular Synthesis of 3,6-Disubstituted-1,2,4-triazines via the Cyclodehydration of β-Keto-<i>N</i>-acylsulfonamides with Hydrazine Salts
作者:Matthew S. Dowling、Wenhua Jiao、Jie Hou、Yuchun Jiang、Shangsheng Gong
DOI:10.1021/acs.joc.8b00254
日期:2018.4.6
A straightforward method for preparing 3,6-disubstituted-1,2,4-triazines through a redox-efficient cyclodehydration of β-keto-N-acylsulfonamides with hydrazine salts is described. Two approaches for synthesizing the requisite β-keto-N-acylsulfonamides are presented, which allow for the late stage incorporation of either the C3 or C6 substituent in a flexible manner from acid chlorides or α-bromoketones
描述了通过β-酮-N-酰基磺酰胺与肼盐的氧化还原有效的环脱水来制备3,6-二取代-1,2,4-三嗪的直接方法。提出了两种合成必需的β-酮-N-酰基磺酰胺的方法,它们允许在后期阶段分别以柔性方式从酰基氯或α-溴代酮掺入C3或C6取代基。该方法的范围包括在C3和C6位置上的伯和仲sp 3连接的取代基,以及温和的反应条件可耐受多种敏感功能。