Arylation of arenes

Scheme 6.11 Arylation of arenes catalyzed by FeCI3 under microwave irradiation. o m p = 12 3 85.

The first case involves direct arylation of arenes with aryl halides via a Pd(0)/Pd (II) cycle (Scheme 8). After initial oxidative addition of Pd(0) into the aryl halide, the C-H bond activation event takes place at the Ar-Pd(II)-X species 4 and is followed by C-C bond forming reductive elimination and regeneration of Pd(0). 

Abstract A review is presented of synthetic methods for the preparation of biaryls by the rhodium-catalyzed C-H bond arylation of arenes with aryl halides (C-H/ C-X couplings), arylmetal reagents (C-H/C-M couplings) and arenes (C-H/C-H couplings), with an emphasis on postulated mechanisms and their implications on reactivity, selectivity and substrate scope. 

Rh-Catalyzed C-H/C-X Arylation of Arenes Through Electrophilic Metalation. 235... 

Scheme 4 General scheme for C-H/C-X arylation of arenes through electrophilic metalation...

Scheme 13 General catalytic cycle for the C-H arylation of arenes through iV-heterocyclic carbene formation [97-104]...

A number of research groups have developed rhodium-catalyzed methods for the C-H bond arylation of arenes that likely proceed through cyclometalated intermediates. Aryl phosphites and phosphinites undergo facile orthometalation... 

Scheme 25 Rh-catalyzed decarbonylative directed C-H arylation of arenes by Zhao and Yu [118]...

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