Highly Selective Cross-Coupling Reactions of Aryl(halo)silanes with Aryl Halides: A General and Practical Route to Functionalized Biaryls

Article abstract of DOI:10.1016/S0040-4020(01)85554-X

The palladium catalyzed cross-coupling reaction of aryl halides with aryl(halo)silanes (halogen=F, Cl) gives good yields of unsymmetrical biaryls and p-terphenyls.The reaction takes place smoothly in N,N-dimethylformamide in the presence of an appropriate palladium catalyst and potassium fluoride.Since this reaction is tolerant of a variety of reactive functional groups, highly functionalized 4,4'-, 3,4'-, 2,4'- and even sterically crowded 2,2'-disubstituted biaryls can be obtained in moderate to high yields.The synthetic utility of the method has been demonstrated by its application to a short synthesis of liquid crystals.Mechanistic aspects of transmetalation of an aryl(fluoro)silicate intermediate with a palladium complex are discussed on the basis of the substituent effects on the rate of the cross-coupling reactions.