Metal-free oxidative decarbonylative coupling of aromatic aldehydes with arenes: direct access to biaryls
作者:Ren-Jin Tang、Qing He、Luo Yang
DOI:10.1039/c4cc10155c
日期:——
A metal-free oxidative decarbonylative coupling of aromatic aldehydes with electron-rich or electron-deficient arenes to produce biaryl compounds was developed. This novel coupling was proposed to proceed via a non-chain radical homolytic aromatic substitution (HAS) type mechanism, based on the substrate scope, ortho-regioselectivity, radical trapping experiments and DFT calculation studies. With the
Microwave-Accelerated Iridium-Catalyzed Borylation of Aromatic C−H Bonds
作者:Peter Harrisson、James Morris、Todd B. Marder、Patrick G. Steel
DOI:10.1021/ol901306m
日期:2009.8.20
accelerates the Ir-catalyzed C−H borylation of aromatic substrates when compared with reactions carried out at the same temperature under standard heating conditions. Application to a one-pot single solvent process for tandem C−H borylation/Suzuki−Miyauracross-coupling sequences using microwave-accelerated reactions gives fast and efficient access to a wide range of biaryl and heterobiaryl compounds.
<i>N</i>,<i>C</i>-Disubstituted Biarylpalladacycles as Precatalysts for ppm Pd-Catalyzed Cross Couplings in Water under Mild Conditions
作者:Ruchita R. Thakore、Balaram S. Takale、Fabrice Gallou、John Reilly、Bruce H. Lipshutz
DOI:10.1021/acscatal.9b04204
日期:2019.12.6
effective palladacycle precatalyst has been identified as that containing an isopropyl group on both an aryl ring and on nitrogen, together with the ligand EvanPhos and triflate as the counterion (P13). This precatalyst is also effective in other C–C bond-forming reactions, such as Heck and Sonogashira couplings. No organic solvents were needed for these processes, while the aqueous reaction medium could be
<i>meta</i>
‐Selective C−H Arylation of Fluoroarenes and Simple Arenes
作者:Luo‐Yan Liu、Jennifer X. Qiao、Kap‐Sun Yeung、William R. Ewing、Jin‐Quan Yu
DOI:10.1002/anie.202002865
日期:2020.8.10
to promote ortho‐C−H metalation. Based upon this reactivity, we employed an activated norbornene that traps the ortho‐palladation intermediate and is then relayed to the meta position, leading to meta‐selective C−H arylation of fluoroarenes. Deuterium experiment suggests that this meta‐arylation is initiated by ortho C−H activation and the catalytic cycle is terminated by C‐2 protonation. A dual‐ligand
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.