Iridium-catalyzed regioselective C–H sulfonamidation of 1,2,4-thiadiazoles with sulfonyl azides in water
作者:Xian-Ting Cao、Su-Ning Wei、Hao-Tian Sun、Meng Li、Zuo-Ling Zheng、Guannan Wang
DOI:10.1039/d1ra04450h
日期:——
We have developed a regioselective C–N cross-coupling of 1,2,4-thiadiazoles with sulfonyl azides throughiridiumcatalysis in water. This method tactically linked the 1,2,4-thiadiazoles and sulfonamides together, and the novel molecules increased the diversity of 1,2,4-thiadiazoles which may have potential applications.
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‐Mediated Synthesis of 1,2,4‐Thiadiazole Derivatives in Ethanol at Room Temperature
作者:Xian‐Ting Cao、Zuo‐Ling Zheng、Jie Liu、Yu‐He Hu、Hao‐Yun Yu、Shasha Cai、Guannan Wang
DOI:10.1002/adsc.202101455
日期:2022.2
Herein, we report the H2O2-mediated synthesis of 1,2,4-thiadiazole derivatives under metal-free conditions at roomtemperature with ethanol as the sole solvent. Various substrates could undergo the reaction smoothly, providing the expected yields of the desired products. Moreover, the target products were obtained by filtration or extraction instead of column chromatography, which requires a large
在此,我们报告了 H 2 O 2介导的 1,2,4-噻二唑衍生物在室温下无金属条件下以乙醇为唯一溶剂的合成。各种底物可以顺利进行反应,提供预期产物的预期产率。此外,目标产物是通过过滤或萃取代替柱层析获得的,在纯化过程中需要大量的有机溶液和硅胶。所开发的合成方法可用于大规模制备 1,2,4-噻二唑衍生物作为农用化学品、药物和功能材料。
Copper-Catalyzed Aerobic Oxidative [3+2] Annulation for the Synthesis of 5-Amino/Imino-Substituted 1,2,4-Thiadiazoles through C–N/N–S Bond Formation
A copper-catalyzed aerobic oxidative annulation reaction of 2-aminopyridine/amidine with isothiocyanate has been reported. This strategy involving C–N/N–S bond formations provides various 5-amino/imino-substituted 1,2,4-thiadiazole derivatives under a Cu/O2 catalytic system. This method has demonstrated high reactivity, mild reaction conditions, and a broad substrate scope. Furthermore, the synthetic
已经报道了2-氨基吡啶/ am与异硫氰酸盐的铜催化的需氧氧化环化反应。这种涉及C–N / N–S键形成的策略可在Cu / O 2催化体系下提供各种5-氨基/亚氨基取代的1,2,4-噻二唑衍生物。该方法显示出高反应活性,温和的反应条件和广泛的底物范围。此外,该方法的综合实用性通过进一步的修改得到了证明。
Catalyst-free, one-pot strategy to access 3-substituted-5-amino-1,2,4-thiadiazoles in water
作者:Chaithra Nagaraju、Swarup Hassan Ashok、Yatheesh Narayana、Sandhya C. Nagarakere、Mantelingu Kempegowda、Rangappa S. Kanchugarkoppal
DOI:10.1080/00397911.2021.1986840
日期:2021.12.2
Abstract A protocol has been devised for the synthesis of 3-substituted 5-amino-1,2,4-thiadiazoles utilizing isothiocyanates, amidoximes and water as an eco-friendly solvent. The strategy involves consecutive C−N and S−N bonds formation in a one-pot reaction under catalyst-free conditions. Operational simplicity, low cost, broad substrate scope and readily available starting materials are the main
摘要 已经设计了一种使用异硫氰酸酯、胺肟和水作为环保溶剂合成 3-取代 5-氨基-1,2,4-噻二唑的方案。该策略涉及在无催化剂条件下的一锅反应中连续形成 CN 和 SN 键。该协议的主要特点是操作简单、成本低、基材范围广泛和易于获得的起始材料。
Oxidative Heterocyclization Using Diethyl Azodicarboxylate
The reactions of amidinothioureas, imidoylthioureas, thioacylamidines, O-methyl-1-aryl-2-thioisobiurets, and 1-aryl-isodithiobiurets with diethyl azodicarboxylate (DEAD, diethyl diazenedicarboxylate) gave the corresponding thiadiazoles by the oxidative cyclic S-N bond formation. Analogously, the oxidative cyclization of 2-phenyl-5-(1-methylthiosemicarbazido)-3(2H)-pyridazinones with DEAD provided 4-methyl-7-phenyl-4H-pyridazino[4,5-e] [1,3,4]-thiadiazin-8(7H)-ones.