Efficient synthesis of <i>N</i>-arylsulfonyl-1,2,3-triazoles from 1,1-dibromo-2-arylethylenes
作者:Wenjing Xu、Wensheng Zhang、Fei Zhang
DOI:10.1515/hc-2016-0051
日期:2016.6.1
Abstract
N-arylsulfonyl-1,2,3-triazoles were synthesized from 1,1-dibromo-2-arylethylenes via a one-pot reaction involving the Cs2CO3-mediated dehydrobromination process of the dibromoalkenes to produce alkynes followed by the Cu(I)-catalyzed Huisgen cycloaddition of the alkyne intermediates with tosyl azide.
N-Alkynylated sulfoximines have been obtained by copper-catalyzed cross-coupling reactions starting from NH-sulfoximines and bromoacetylenes in moderate to good yields. The reaction conditions are mild, and the substrate scope is wide.
The copper(II)-catalyzed (4+1) cyclizations and copper(I)-catalyzed (3+2) cycloadditions of iodonium ylides and alkynes were successfully developed by employing efficient and safe iodonium ylides instead of traditional diazo compounds. Highly functionalized dimethyl (E)-3-benzylideneindoline-2,2-dicarboxylates and methyl 5-(2-hydroxyphenyl)-2-methoxy-4-phenylfuran-3-carboxylates were conveniently prepared
Visible Light‐Catalyzed Decarboxylative Alkynylation of Arenediazonium Salts with Alkynyl Carboxylic Acids: Direct Access to Aryl Alkynes by Organic Photoredox Catalysis
salts have been utilized as the aryl radical source to couple alkynyl carboxylic acids to feature the decarboxylative arylation. A wide range of substrates are amenable to this protocol with broad functional group tolerance, and diversely‐functionalized aryl alkynes could be synthesized undermild, neutral and transition metal‐free reaction conditions using visiblelight irradiation. Alongside synthetic
Nickel-Catalyzed Difunctionalization of Alkynyl Bromides with Thiosulfonates and N-Arylthio Succinimides: A Convenient Synthesis of 1,2-Thiosulfonylethenes and 1,1-Dithioethenes
cesium carbonate is described. An operationally simple and highly regioselective atom transfer radical addition (ATRA) of alkynyl bromides provides a wide range of (E)-1,2-thiosulfonylethenes (α-aryl-β-thioarylvinyl sulfones) in moderate to high yields. The extensive substrate scope of both alkynyl bromides and thiosulfonates is explored with a broad range of functional groups. Indole-derived 1,1-bromoalkenes