A C–H Borylation Approach to Suzuki–Miyaura Coupling of Typically Unstable 2–Heteroaryl and Polyfluorophenyl Boronates
摘要:
A method for the synthesis of biaryls and heterobiaryls from arenes and haloarenes without the intermediacy of unstable boronic acids is described. Pinacol boronate esters that are analogous to unstable boronic acids are formed in high yield by iridium-catalyzed C-H borylation of heteroarenes and fluoroarenes. These boronates are stable in the solid state or in solution and can be generated and used in situ. They couple with aryl halides in the presence of simple palladium catalysts, providing a convenient route to biaryl and heteroaryl products that have been challenging to prepare via boronic acids.
Sterically Controlled Alkylation of Arenes through Iridium-Catalyzed CH Borylation
作者:Daniel W. Robbins、John F. Hartwig
DOI:10.1002/anie.201208203
日期:2013.1.14
one‐pot method for the site‐selective alkylation of arenes controlled by steric effects is reported. The process occurs through Ir‐catalyzed CHborylation, followed by Pd‐ or Ni‐catalyzed coupling with alkyl electrophiles. This selectivity complements that of the typical Friedel–Crafts alkylation; meta‐selective alkylation of a broad range of arenes with various electronic properties and functional