metal-free approach for the synthesis of 5-trifluoromethyl-1,2,4-triazoles via I2-mediated [4+1] annulation of readily available trifluoroacetimidohydrazides and methyl ketones has been achieved. The transformation involves iodination/Kornblum oxidation, intermolecular dehydration condensation and an iodine-mediated intramolecular cyclization/aromatization sequence. The developed protocol can be easily scaled
已经实现了一种通过 I 2介导的 [4+1] 环化容易获得的三氟乙酰氨基酰肼和甲基酮来合成 5-三氟甲基-1,2,4-三唑的无金属方法。该转化包括碘化/Kornblum 氧化、分子间脱水缩合和碘介导的分子内环化/芳香化序列。开发的协议可以很容易地扩展到 3 mmol 规模而不会明显降低效率,并且可以通过连续的一锅方式实施。
Oxidative Cyclization of Trifluoroacetimidohydrazides with D‐Glucose for the Metal‐Free Synthesis of 3‐Trifluoromethyl‐1,2,4‐Triazoles
A metal-free oxidative cyclization of readily available trifluoroacetimidohydrazides with D-glucose for the assembly of 3-trifluoromethyl-1,2,4-triazoles has been disclosed. D-glucose is applied as C1 synthon to provide methine source in the reaction. Control experiments have been conducted to shed light on the reaction mechanism. The synthetic utility of the protocol has been explored by the implementation
已经公开了易于获得的三氟乙酰氨基酰肼与 D-葡萄糖的无金属氧化环化,用于组装 3-三氟甲基-1,2,4-三唑。D-葡萄糖用作 C1 合成子以在反应中提供次甲基源。已经进行了对照实验以阐明反应机理。该协议的合成效用已通过扩大反应的实施和 NK I受体配体的关键骨架的合成进行了探索。
Trifluoromethylated Amidrazone Derivatives as Key Compounds for the Synthesis of 4-Aryl-3,5-bis(trifluoromethyl)-4H-1,2,4-triazoles
作者:Najmeh Zeinali、Ali Darehkordi
DOI:10.1055/a-1933-3655
日期:2023.2
for the synthesis of aryl-3,5-bis(trifluoromethyl)-4H-1,2,4-triazoles is disclosed via the nucleophilic intramolecular cyclization reaction of trifluoromethylated amidrazone and 2,2,2-trifluoroacetic anhydride. The trifluoromethylated amidrazone intermediates used in this project are synthesized from the reaction of N-aryl-2,2,2-trifluoroacetimidoyl chloride derivatives and hydrazine hydrate at ambient
通过三氟甲基化脒腙和 2,2 的亲核分子内环化反应,公开了一种新型、高效、无溶剂合成芳基-3,5-双(三氟甲基)-4 H -1,2,4-三唑的方法,2-三氟乙酸酐。本项目使用的三氟甲基化脒腙中间体是由N-芳基-2,2,2-三氟乙酰亚胺酰氯衍生物与水合肼在常温下反应合成,收率极佳。
A facile and catalyst-free microwave-promoted method for the synthesis of 3-trifluoromethyl 1,2,4-triazole-5-thiones
作者:Najmeh Zeinali、Ali Darehkordi
DOI:10.1016/j.tetlet.2023.154727
日期:2023.10
a fast, simple, efficient, and eco-friendly procedure for the synthesis of 4-aryl-3-(trifluoromethyl)-1H-1,2,4-triazole-5(4H)-thiones undermicrowaveirradiation is introduced. The current strategy enabled the synthesis of triazole-5(4H)-thiones scaffolds at 70 °C under shorter reaction times through the sequential nucleophilic addition and then intramolecular ring closing reactions between trifluoromethyl
Elemental Sulfur and Dimethyl
<scp>Sulfoxide‐Promoted</scp>
Oxidative Cyclization of Trifluoroacetimidohydrazides with Methylhetarenes for the Synthesis of
<scp>3‐Hetaryl</scp>
‐5‐trifluoromethyl‐1,2,4‐triazoles
Main observation and conclusionA metal‐free approach for the synthesis of 3‐hetaryl‐5‐trifluoromethyl‐1,2,4‐triazoles via sulfur/dimethyl sulfoxide‐promoted oxidative cyclization of readily available trifluoroacetimidohydrazides with methylhetarenes has been developed. This transformation proceeds in cascade sulfur‐mediated generation of thioaldehyde, condensation, intramolecular cyclization and oxidative aromatization sequence.