Regioselective cross-coupling reactions of multiple halogenated nitrogen-, oxygen-, and sulfur-containing heterocycles

Catalyst-Controlled Site-Selectivity Switching in Pd-Catalyzed Cross-Coupling of Dihaloarenes

“…In comparison with the chemoselective cross-coupling, it is difficult to achieve siteselective cross-coupling of substrates where both halo groups are the same. Nevertheless, because these substrates can generally be prepared in shorter steps than the compounds with two different halo groups, this type of site-selective cross-coupling can prove more useful for the synthesis of multisubstituted arenes [12][13][14][15]. Therefore, it is highly desirable to develop efficient site-selective cross-coupling of dihaloarenes.…”

Ortho-selective Cross Coupling of Dibromophenols and Dibromoanilines with Grignard Reagents in the Presence of Palladium Catalysts Bearing Hydroxylated Oligoarene-type Phosphine

“…For multiply halogenated heteroarenes, many examples of site-selective cross coupling have been reported. 1 For multiply halogenated benzene derivatives, however, only a few examples have been reported, 2 and the reactions mainly occur at less electronically negative carbons. For example, Singh and Just reported the selective Sonogashira coupling in which dibromoanilines underwent the coupling preferentially at the meta-position over the ortho-or para-position.…”

Efficient synthesis of differently substituted triarylpyridines with the Suzuki-Miyaura cross-coupling reaction

“…This may be explained on the basis of the well accepted mechanism of the palladium-catalysed cross-coupling reaction. [39][40][41][42] The catalytic cycle starts with the oxidative-addition of the aryl halide to a Pd(0) complex to form arylpalladium(II) halide intermediate. After ligand exchange between the complex and the base, transmetallation with the arylboronic acid occurs followed by reductive elimination leading to the final product.…”