No abstract

The first example of the Pd-catalyzed addition of organoboron reagents to dinitriles, as an efficient means of preparing 2,5-diarylpyrroles and 2,6-diarylpyridines, has been discussed here. Furthermore, the highly selective carbopalladation of dinitriles with organoboron reagents to give long-chain ketonitriles has been developed as well. Based on the broad scope of substrates, excellent functional group tolerance, and use of commercially available substrates, the Pd-catalyzed addition reaction of arylboronic acid and dinitriles is expected to be significant in future synthetic procedures.

The first example of nickel complexes as effectively catalyst to C–C, N–C cascade coupling of ketonitriles with arylboronic acids, affording 2,5-diarylpyrroles and 2,6-diarylpyridines.

This study presents the first example of the Pdcatalyzed cascade reactions of 5-oxohexanenitrile with arylboronic acids, affording important synthon 2-methylpyridines that can be further translated through C(sp 3 )-H functionalization to construct pyridine derivatives. Furthermore, this chemistry allows 5-oxo-5arylpentanenitrile to react with arylboronic acids to provide unsymmetrical 2,6-diarylpyridines. This protocol paves the way for the practical and atom economical syntheses of valuable pyridines with broad functional groups in moderate to excellent yields under mild conditions.

A palladium-catalyzed cascade reaction of 2′-acetyl-[1,1′-biphenyl]-2-carbonitriles with arylboronic acids is developed. This reaction affords a new class of seven-membered 5-arylidene-7-aryl-5H-dibenzo­[c,e]­azepines with good functional group compatibility and selectivity. Reaction mechanistic study suggests that this transformation involves carbopalladation of nitrile and subsequent intramolecular cyclization followed by oxidative Heck coupling.