Aryl halides with arylboronic acids

Diaryl ketones.Pd-catalyzed cross-coupling of aryl halides with arylboronic acids under 1 atmosphere of CO provides these products. With highly hindered ArB(OH>2 such as mesitylboronic acid, good yields of the ketones are obtained only with Arl (not ArBr). 

The Suzuki reaction of arylboronic acid derivatives with aryl halides is one of the most powerful methods for construction of an unsymmetrically substituted biaryl derivative [11, 23, 85]. Due to the importance of substituted biaryls as building blocks for pharmaceuticals, there is currently a great deal of interest in the coupling of economically attractive aryl halides with arylboronic acids [86-98]. 

Palladacycles prepared by the addition of furancarbothioamide to a methanol solution of Li2PdCl4 at room temperature are soluble in hexane, chloroform, and moderately soluble in polar solvents DMF and DMSO [187]. These palladacycles are thermally stable, not sensitive to air or moisture, and can be applied effectively in the Heck reaction of aryl halides with terminal olefins and in the Suzuki reaction of aryl halides with arylboronic acids. These reactions were performed under aerobic conditions, leading to turnover numbers... 

The palladium-catalysed Suzuki coupling reaction of aryl halides with arylboronic acids has proved to be a general and convenient synthetic tool employed in organic chemistry to prepare biaryl compounds.[1] The discovery and development of active and efficient palladium-catalyst systems have been the focus of great interest recently. New catalytic systems based on paUadium-oxazolines, such as 2-aryl oxazolines and 2,2 -(l,3-phenylene)bisoxazoline (Figure 4.1) have been developed for the coupling reaction. These catalytic systems have the potential to overcome... 

Finally, the Suzuki-Miyaura reaction, which has become one of the most versatile and important reactions for the construction of C-C bonds, could be performed in a continuous flow process under ligand-free conditions [43]. The PASSfiow reactor is suited for the coupling of 4-iodoacetophenone and other aryl halides with arylboronic acid to yield the corresponding diaryls within 3 h without formation of homocoupling by-products (Scheme 15). After collecting... 

Table 9. The required amount of the palladium precatalysts with different phosphine ligands in the Suzuki-Miyaura reactions of various aryl halides with arylboronic acids...

Suzuki coupling of aryl halides with arylboronic acids is a powerful reaction for the construction of biaryl units in organic synthesis [34]. It is a versatile approach for cross coupling reactions, which have been the subject of intensive research. 

Suzuki coupling reaction of polymer-bound aryl halides with arylboronic acids and a palladium catalyst was described by Larhed et al. [132]. The reagents in a mixture of ethylene glycol dimethyl ether (DME) and water were irradiated (ca. 4 min) in a heavy-walled Pyrex tube (Fig. 36) placed in a single-mode microwave reactor. 

---