A General Pd-Catalyzed Decarboxylative Cross-Coupling Reaction between Aryl Carboxylic Adds: Synthesis of Biaryl Compounds

摘要

Biaryl compounds have fascinated chemists for over 100 years because of their scientific and commercial value, and they are still a focus of interest to synthetic chemists. Over the past three decades, the persistent efforts of synthetic chemists to develop efficient methods for transition-metal-catalyzed cross-coupling reactions have revolutionized the synthesis of biaryl compounds. These methods, in particular palladium-catalyzed cross-coupling reactions between aryl halides and aryl organometallics, are widely used in modern academic and industrial laboratories, but some limitations still remain. Traditional cross-coupling methods require pre-activated coupling partners, such as expensive and/or moisture-sensitive organometallic reagents, and frequently produce unwanted, often toxic, stoichiometric side-products. Demands for a sustainable development of society have provided the impetus for chemists to develop more atom-economical and greener reactions. In this context, significant advances have recently been made in the development of catalytic methods for the direct arylation of aromatic C-H bonds, thus offering a very promising way to generate valuable biaryl compounds from simple starting materials in an atom- and step-economical fashion. Although many elegant studies have demonstrated that high selectivity can be achieved in such direct arylation reactions by tuning directing groups, electronic effects, and steric factors, significant room for improvement remains.