Cross-coupling of polychloroarenes with phenylboronic acid and organozinc compounds catalyzed by palladium complexes

Abstract

Hexachlorobenzene and 1,2,4,5 tetrachlorobenzene react with phenylboronic acid by a С-С cross coupling mechanism with a Pd(dba) 2 /P(Bu t ) 3 system (dba is dibenzylideneacetone) or palladium azole complexes as catalysts, or with organozinc compounds in the presence of Pd(PPh 3 ) 4 to afford substitution products of one or two chlorine atoms in moderate yields.

Cross-coupling of polychlorobenzenes with phenylboronic acid in the presence of [Pd]-imidazolium salts as catalytic systems

“…1,2 These transformations open up a one step route to func tionally substituted arenes and polyarylbenzenes from readily available and inexpensive polychloroaromatic compounds (PCA). In the case of less nucleophilic arylboronic acids, low reactivity of PCA required the use of special catalytic systems comprising electron enriched sterically hindered phosphine ligands 3 or N hetero cyclic carbene palladium complexes.…”

Bis(tetrazolyl)benzenes as ligands in the Suzuki reaction: Promoters or inhibitors?

“…The inhibitive effects of compounds 1-5 were especially pronounced in reactions with less reactive chloroarenes (entries [15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32]. The reaction is doubly af fected by PTC: they can both increase (e.g., 8e) and de crease the yields of cross coupling products (8f).…”