We report the metal-free chalcogenation of cycloketone oxime esters with dichalcogenides via a radical process. Because of the metal-free condition and use of readily accessible dichalcogenides, this method is an effective and green strategy for the synthesis of chalcogen-substituted butyronitrile.
A mild copper-catalyzed four-component selenosulfonylation of alkynes, cycloketone oxime esters, DABCO (SO2)2 and diselenides has been developed. This method enables the rapid assembly of β-cyanoalkylsulfonylated vinyl selenides in moderate to good yields. Advantages of this protocol include a broad substrate scope, good functional group tolerance and the late-stage functionalization of complex molecules
Copper-catalyzed aryl selenylation of 2-bromodifluoromethylbenzo-1,3-thi(x)azoles with diaryl diselenides
作者:Rong-Fu Xu、Fu-Min Liao、Ying Cai、Jin-Biao Liu
DOI:10.1016/j.tet.2022.133118
日期:2022.12
An efficient method of copper-catalyzed aryl selenylation of 2-bromodifluoromethylbenzo-1,3-thi(x)azoles with diaryl diselenides was described to prepare gem-difluoromethylene moiety linked aryl seleno compounds. Under the optimized conditions, various 2-bromodifluoromethylbenzo-1,3-thi(x)azoles can be coupled with a range of diaryl diselenides to give their corresponding Se-containing gem-difluoroalkyl
Visible-Light-Mediated Regioselective C3–H Selenylation of Pyrazolo[1,5-<i>a</i>]pyrimidines Using Erythrosine B as Photocatalyst
作者:Tathagata Choudhuri、Suvam Paul、Sourav Das、Devendra Deo Pathak、Avik Kumar Bagdi
DOI:10.1021/acs.joc.3c00720
日期:2023.7.7
visible-light-induced efficient methodology has been developed for the C–H selenylation of pyrazolo[1,5-a]pyrimidine derivatives employing erythrosine B as the photocatalyst. This is the first report on the regioselective selenylation of pyrazolo[1,5-a]pyrimidines. The efficiency of this methodology for the selenylation of different electron-rich heterocycles like pyrazole, indole, imidazo[1,2-a]pyridine, imidazo[2,1-b]thiazole
采用赤藓红 B 作为光催化剂,开发了一种可见光诱导的吡唑并[1,5- a ]嘧啶衍生物C-H 硒化的有效方法。这是关于吡唑并[1,5- a ]嘧啶区域选择性硒化的第一份报告。该方法对不同富电子杂环(如吡唑、吲哚、咪唑并[1,2- a ]吡啶、咪唑并[2,1- b ]噻唑和4-(苯氨基)-2 H)的硒化效率-chromen-2-one 也已得到证实。探索赤藓红B作为光催化剂的过程简单温和、底物范围广、实用性强以及使用环保的能源、氧化剂和溶剂是该方法的吸引人的特点。
Copper-Catalyzed Regioselective 1,4-Selenosulfonylation of 1,3-Enynes to Access Cyanoalkylsulfonylated Allenes