Synthesis of Unsymmetrical Diorganyl Chalcogenides under Greener Conditions: Use of an Iodine/DMSO System, Solvent- and Metal-Free Approach
作者:Sumbal Saba、Jamal Rafique、Antonio L. Braga
DOI:10.1002/adsc.201500024
日期:2015.5.4
Herein, we report a greeneriodine‐catalyzed protocol to access different types of unsymmetricaldiorganylchalcogenides. This new approach works in the absence of solvent and metal. The desired products were obtained in good to excellent yields using one equivalent of arylboronic acids, half an equivalent of various diorganyl dichalcogenides, iodine (10 mol%) as a catalyst and 2 equivalents of dimethyl
Synthesis of symmetrical and unsymmetrical tellurides <i>via</i> silver catalysis
作者:Bruna Goldani、Manoela do Sacramento、Eder J. Lenardão、Ricardo F. Schumacher、Thiago Barcellos、Diego Alves
DOI:10.1039/c8nj01998c
日期:——
cross-coupling reaction of diaryl ditellurides with aryl boronic acids catalyzed by AgNO3. The general applicability and wide substrate scope make this an interesting method for the synthesis of a series of symmetrical and unsymmetrical diaryl tellurides. This silver-catalyzed protocol tolerates a variety of diaryl ditellurides as well as aryl boronic acids by using only 10 mol% of AgNO3 to provide the desired
我们在这里描述了一种简单有效的方法,用于二芳基二碲化物与AgNO 3催化的芳基硼酸的交叉偶联反应。通用性和广泛的底物范围使该方法成为合成一系列对称和不对称二芳基碲化物的有趣方法。该银催化的方案通过仅使用10 mol%的AgNO 3来耐受多种二芳基二碲化物和芳基硼酸,从而以高收率提供所需的产物。通过高分辨率质谱分析提出了该反应机理,并可以检测出活性的(PhTe)2 Ag III中间体。
Convenient Synthesis of Unsymmetrical Organochalcogenides Using Organoboronic Acids with Dichalcogenides via Cleavage of the S−S, Se−Se, or Te−Te Bond by a Copper Catalyst
作者:Nobukazu Taniguchi
DOI:10.1021/jo062131+
日期:2007.2.1
describes the methodology for a copper-catalyzed preparation of numerous monochalcogenides from dichalcogenides with organoboronic acids. Unsymmetrical diorgano-monosulfides, selenides, and tellurides can be synthesized by the coupling of dichalcogenides with aryl- or alkylboronic acids using a copper catalyst in air. The present reaction can take advantage of both organochalcogenide groups on dichalcogenide
substitution (SH2) reaction between the aryl radical and diaryl ditelluride. Aryl radicals are generated from arylhydrazines in air and captured by diaryl ditellurides, resulting in a selective formation of unsymmetrical diaryl tellurides with high yields. The electronic effects of the substituents on both arylhydrazines and diaryl ditellurides on the SH2 reaction of tellurium are also discussed in detail.
A convenient and efficient copper-catalyzed synthesis of unsymmetrical and symmetrical diaryl chalcogenides from arylboronic acids in ethanol at room temperature
作者:Amit Kumar、Sangit Kumar
DOI:10.1016/j.tet.2014.01.030
日期:2014.3
A simple and convenient approach for the synthesis of unsymmetrical diaryl chalcogenides (Te, Se, and S) has been developed by copper-catalyzed cross-coupling reaction of organoboronic acid with diaryl dichalcogenide in ethanol using NaBH4 in air or oxygen. The present methodology is highly practical for the synthesis of unsymmetrical diaryl tellurides with various functionalities such as -NO2, -F, -Br, and -COOH that have been obtained in good to excellent yields. Methodology is also effective for the synthesis of unsymmetrical diaryl selenides and sulfides. Moreover, symmetrical diaryl selenides have also been obtained from arylboronic acids using elemental selenium powder under optimized reaction conditions. The use of NaBH4 is the key for the development of milder reaction conditions, which enable the construction of unsymmetrical diaryl chalcogenides from boronic acid substrates in ethanol at room temperature. (C) 2014 Elsevier Ltd. All rights reserved.