Visible-Light-Induced C(sp<sup>2</sup>)–C(sp<sup>3</sup>) Coupling Reaction for the Regioselective Synthesis of 3-Functionalized Coumarins
作者:Ke Zhang、Li Qiao、Jianwei Xie、Zhenwei Lin、Hanjie Li、Ping Lu、Yanguang Wang
DOI:10.1021/acs.joc.1c00848
日期:2021.7.16
A photocatalysis strategy for the regioselective synthesis of 3-functionalized coumarins is reported. With visible light irradiation, a direct and regioselective C(sp2)–C(sp3) coupling reaction of 3-(2-hydroxyphenyl)acrylates with ethers or thioethers occurs by using Ru(bpy)3Cl2·6H2O as a photocatalyst and TBHP as an oxidant. The cascade process involves alkenylation of the C(sp3)–H bond of ethers
Using lithiation reaction, four methoxy and hydroxynaphthaldehydes have been synthesised. Three of these have been converted into the corresponding naphthofurans and benzocoumarins.