Reactions of trimethylsilyl azide with aldehydes: facile and convenient syntheses of diazides, tetrazoles, and nitriles
作者:Kozaburo Nishiyama、Makoto Oba、Akio Watanabe
DOI:10.1016/s0040-4020(01)90003-1
日期:——
The reactions of trimethylsilylazide (TMSA) with various aldehydes were found to be versatile procedures for the synthesis of gem- and 1,3-diazides, tetrazoles, and nitriles, whose formation was varied by controlling the quantities of TMSA, catalyst, and the reaction conditions.
Highly efficient synthesis of 1- and 5-substituted 1H-tetrazoles using chitosan derived magnetic ionic liquid as a recyclable biopolymer-supported catalyst
作者:Ali Khalafi-Nezhad、Somayeh Mohammadi
DOI:10.1039/c3ra23107k
日期:——
A general method for the efficient synthesis of 1- and 5-substituted1H-tetrazoles from nitriles and amines is described using chitosan supported magnetic ionic liquid nanoparticles (CSMIL) as a novel heterogeneous catalyst. The application of this catalyst allows the synthesis of a variety of tetrazoles in high yields at low temperature. This new magnetic catalyst has been prepared from chitosan (the
ABSTRACT: N1-substituted tetrazoles are interesting ligands in transition metal coordination chemistry, especially in the field of spin crossover. Their synthesis is performed in most cases according to the Franke-synthesis, using a primary amine as reagent introducing the substitution pattern. To enhance flexibility in means of substrate scope, we developed a new protocol based on alkylation of lithium
One-pot synthesis of 1- and 5-substituted 1<i>H</i>-tetrazoles using 1,4-dihydroxyanthraquinone-copper(II) supported on superparamagnetic Fe<sub>3</sub>O<sub>4</sub>@SiO<sub>2</sub>magnetic porous nanospheres as a recyclable catalyst
magnetic nanocatalyst with core–shell structure is presented by using nano‐Fe3O4 as the core, tetraethoxysilane as the silica source and poly(vinyl alcohol) as the surfactant, and then Fe3O4@SiO2 was coated with 1,4‐dihydroxyanthraquinone–copper(II) nanoparticles. The new catalyst was characterized using Fourier transform infrared spectroscopy, X‐ray diffraction, transmission electron microscopy, field
利用负载在Fe 3 O 4 @SiO 2磁性多孔纳米球上的1,4-二羟基蒽醌-铜(II),描述了一种从腈和胺合成1-和5-取代的1 H-四唑的有效的一锅便捷方法。作为一种新型的可回收催化剂。该催化剂的应用允许以良好至优异的产率合成多种四唑。以纳米Fe 3 O 4为核,四乙氧基硅烷为二氧化硅源,聚乙烯醇为表面活性剂,然后Fe 3 O 4 @SiO 2,制备了具有核-壳结构的磁性纳米催化剂。用1,4-二羟基蒽醌-铜(II)纳米颗粒涂覆。使用傅里叶变换红外光谱,X射线衍射,透射电子显微镜,场发射扫描电子显微镜,动态光散射,热重分析,振动样品磁力分析,X射线光电子能谱,氮吸附-解吸等温线分析和电感耦合等离子体分析。该新方法具有许多优点,例如反应时间短,产率高,操作简便,实用性和对各种底物的适用性,并且无需任何繁琐的后处理或纯化。此外,出色的催化性能,热稳定性和催化剂的分离使其成为良好的多相体系,并
Facile synthesis of 1- and 5-substituted 1H-tetrazoles catalyzed by recyclable ligand complex of copper(II) supported on superparamagnetic Fe3O4@SiO2 nanoparticles
coupled plasma (ICP) analyzer. Then, the immobilized copper complex was used as an efficientcatalyst for synthesis of 1- and 5-substituted1H-tetrazolesfromnitriles and amines in good to excellent yields. The results show that the supported catalyst could be conveniently recovered through the use of an external magnetic field and reused for subsequent reactions for at least 6 times with less deterioration
我们报告了一种新的制备具有高饱和磁化强度的超顺磁性Fe 3 O 4 @SiO 2的新方法。通过简单的共沉淀法在水介质中制备磁铁矿颗粒,然后以纳米Fe 3 O 4为核,TEOS为二氧化硅源,聚乙二醇(PEG 1000)为纳米材料,合成Fe 3 O 4 @SiO 2纳米球。表面活性剂。然后,二氧化硅涂覆的Fe 3 O 4纳米粒子被铜(II)的配体络合物覆盖。通过傅立叶变换红外光谱,透射电子显微镜,扫描电子显微镜,X射线衍射,热重分析,动态光散射和N 2吸附/解吸研究了功能化的核壳纳米粒子(MNP)。另外,其铜含量是通过电感耦合等离子体(ICP)分析仪测定的。然后,将固定的铜络合物用作合成1和5取代的1 H的有效催化剂-来自腈和胺的四唑类,收率好至极好。结果表明,可通过使用外部磁场方便地回收负载的催化剂,并将其再用于后续反应至少6次,而催化活性的降低较小。