A general and efficient method for the direct alkynylation of unactivatedC(sp3)-H bondsunder metal-free condition is described. The reaction smoothly performs undermildconditions and shows excellent functional-group tolerance....
KOAc-promoted alkynylation of α-C–H bonds of ethers with alkynyl bromides under transition-metal-free conditions
作者:Jiajun Zhang、Pinhua Li、Lei Wang
DOI:10.1039/c4ob00002a
日期:——
KOAc-promoted α-position C–H activation and alkynylation of ethers with alkynyl bromides to 2-alkynyl ethers was developed under transition-metal-free conditions.
Decatungstate as Direct Hydrogen Atom Transfer Photocatalyst for SOMOphilic Alkynylation
作者:Luca Capaldo、Davide Ravelli
DOI:10.1021/acs.orglett.1c00381
日期:2021.3.19
A versatile approach for the alkynylation of a variety of aliphatic hydrogen donors, including alkanes, is reported. We used tetrabutylammonium decatungstate as photocatalyst to generate organoradicals from C–H/Si–H bondsvia hydrogen atom transfer. The latter intermediates underwent SOMOphilic alkynylation by methanesulfonyl alkynes to afford internal alkynes upon loss of a sulfonyl radical. The effect
A metal-free direct alkylation of CâH bonds adjacent to an oxygen or nitrogen atom was developed. This reaction occurred between saturated heterocycles and ethynylbenziodoxolones under mild conditions. A series of 2-alkynyl cyclic alkanes that contain oxygen or nitrogen atoms were prepared in moderate to good yields.
Visible‐Light‐Induced Alkynylation of α‐C–H Bonds of Ethers with Alkynyl Bromides without External Photocatalyst
作者:Xiaofei Xie、Jie Liu、Lei Wang、Min Wang
DOI:10.1002/ejoc.201900872
日期:2020.3.15
An unprecedented direct alkynylation reaction of α‐C(sp3)–H bonds of ethers under visiblelight irradiation at room temperature withoutexternalphotocatalyst was developed.