<i>meta</i> C–H Arylation of Electron-Rich Arenes: Reversing the Conventional Site Selectivity
作者:Luo-Yan Liu、Jennifer X. Qiao、Kap-Sun Yeung、William R. Ewing、Jin-Quan Yu
DOI:10.1021/jacs.9b07887
日期:2019.9.18
report the first catalytic system that effectively performs meta C-Harylation of a variety of alkoxy aromatics including 2,3-dihydrobenzofuran and chromane with exclusive meta site-selectivity, thus reversing the conventional site selectivity governed by native electroniceffects. The identification of an effective ligand and modified norbornene (NBE-CO2Me), as well as taking advantage of the statistics
Methyl tert-butyl ether is a suitable solvent for iridium-catalyzed C-H borylation followed, in the same pot, by palladium-catalyzed Suzuki-Miyaura cross-coupling sequences, giving high yields of biaryls.
An efficient directing group free C−Harylation of anisoles via Pd/S,O-ligand catalytic system is reported. This method can be applied to a wide variety of anisole derivatives and aryl iodides and is also applicable for late-stage arylation of bioactive molecules.