KI-catalyzed oxidative cyclization of α-keto acids and 2-hydrazinopyridines: efficient one-pot synthesis of 1,2,4-triazolo[4,3-<i>a</i>]pyridines
作者:De-Suo Yang、Juan Wang、Peng Gao、Zi-Jing Bai、Dong-Zhu Duan、Ming-Jin Fan
DOI:10.1039/c8ra06215c
日期:——
A one-pot approach to substituted 1,2,4-triazolo[4,3-a]pyridines has been developed that is based on a KI-catalyzed oxidative cyclization of α-keto acids and 2-hydrazinopyridines. This transition-metal-free procedure was highly efficient and shows good economical and environmental advantages.
基于 KI 催化的 α-酮酸和 2-肼基吡啶的氧化环化,开发了一种取代 1,2,4-三唑并[4,3- a ]吡啶的一锅法。这种不含过渡金属的工艺非常高效,并显示出良好的经济和环境优势。
An iodobenzenediacetate (IBD)-mediated simple and green method was determined for the intramolecular oxidative cyclization of 3-aryl-2-pyridiylhydrazones of different aromatic aldehydes in an aqueous medium at room temperature. This efficient strategy provides a route to the synthesis of 3-aryl-1,2,4-triazolo[4,3-a]pyridines in water which eliminates the requirement to use costly and unsafe volatile
A green one-pot process for the synthesis of 1,2,4-triazole-fused heterocycles using FeBr3 catalyst and hydrogen peroxide
作者:Yuliang Pan、Ruotong Tian、Yini Chen、Linyang Wang、Huilin Qin、Jian Wang
DOI:10.1016/j.tet.2023.133688
日期:2023.11
An environmentally benign oxidative cyclization utilizing FeBr3 catalyst and hydrogen peroxide as terminal oxidant is devised for one-pot synthesis of 1,2,4-triazole-fused heterocycles from commercially available aliphatic or (hetero)aromatic aldehydes and 2-hydrazinopyridine derivatives. The protocol features mild conditions, simple operation, air/water tolerance, short reaction time, and waste prevention
A one-pot method has been devised for the synthesis of 1,2,4-triazole-fused heterocycles. This method involves the condensation of commercially available (hetero)aromatic/aliphatic aldehydes and 2-hydrazinopyridine derivatives, succeeded by iron-catalyzedoxidation using O in air as the oxidant and without using any ligands or additives. The salient merits of this chemistry include broad substrate