Site-Selective Copper-Catalyzed Azidation of Benzylic C–H Bonds
摘要:
Site selectivity represents a key challenge for non-directed C-H functionalization, even when the C-H bond is intrinsically reactive. Here, we report a copper-catalyzed method for benzylic C-H azidation of diverse molecules. Experimental and density functional theory studies suggest the benzyl radical reacts with a Cu-II-azide species via a radical-polar crossover pathway. Comparison of this method with other C-H azidation methods highlights its unique site selectivity, and conversions of the benzyl azide products into amine, triazole, tetrazole, and pyrrole functional groups highlight the broad utility of this method for target molecule synthesis and medicinal chemistry.
A mild and efficient method for preparation of azides from alcohols using acidic ionic liquid [H-NMP]HSO4
作者:Abdol R. Hajipour、Asiyeh Rajaei、Arnold E. Ruoho
DOI:10.1016/j.tetlet.2008.11.111
日期:2009.2
We report here an efficientmethod for the synthesis and characterization of [H-NMP]HSO4 and its application as an efficient catalyst and solvent for preparation of azides from corresponding alcohols under mild conditions. This processor showed high chemoselectivity for conversion of various alcohols to their corresponding azides.
One-pot Green Synthesis of Azides from Alcohols Using Brønsted Acidic Ionic Liquid [HMIM][BF<sub>4</sub>] as Solvent and Catalyst
作者:Bhaskar Garg、Yong-Chien Ling
DOI:10.1002/jccs.201400046
日期:2014.7
Brønstedacidicionicliquid, [HMIM][BF4], has been used as a non‐volatile, eco‐friendly solvent, and catalytic medium for the one‐pot greensynthesis of azidesfrom corresponding alcohols. The [HMIM][BF4] showed high reactivity than [BMIM][BF4] and [BMIM][PF6], affording azides in up to 97% yield, which could be easily separated from the reaction mixture. The ease of recyclability of [HMIM][BF4] makes
Transition-metal-free azide insertion of <i>N</i>-triftosylhydrazones using a non-metallic azide source
作者:Xueyu Li、Jin-Na Song、Swastik Karmakar、Ying Lu、Ye Lv、Peiqiu Liao、Zhaohong Liu
DOI:10.1039/d2cc05442f
日期:——
Benzylic azides, an important class of active organic synthons, were synthesized in high yields from the easily accessible N-triftosylhydrazones with stable TMSN3 under mild conditions. The reaction features high efficiency and excellent functional group tolerance, as illustrated by gram-scale synthesis and the synthesis of drug-like molecules. Mechanistic studies reveal that azidation occurs at the
苄基叠氮化物是一类重要的活性有机合成子,在温和条件下从易于获得的具有稳定 TMSN 3的N -triftosylhydrazone 以高产率合成。该反应具有高效和优异的官能团耐受性,如克级合成和类药分子的合成所示。机理研究表明,通过叠氮离子消除 N 2,在缺电子的重氮碳中发生叠氮化。