Avis de soutenance de thèse de Doctorat (Cotutelle) de Mlle BENZAI Amal le: 09/11/2021

The direct arylation catalyzed by a transition metal by cleavage of C-H bondshas opened up new perspectives in organic synthesis, in particular through the use of a homogeneous catalyst. The work done during this thesis is part of this context.The work carried out during this thesis falls within this context. In a first step, we use this method of arylation of C-H bonds catalyzed by palladium to pharmaceuticals such as bifonazole, Climbazole and Prochloraz based on imidazole.In the presence of phosphine-free Pd (OAc) 2 catalyst, aryl bromides are efficiently coupled at the C5-position of the imidazole units, which are widely decorated. Under these conditions, only C − H bond arylation reaction occurred without affecting the integrity of chemical structure of the imidazole-based pharmaceuticals. Moreover, with Bifonazole Pd-catalyzed C − H bond diarylation at the C2- and C5-positions of imidazole unit has also been performed.In the second part, we report the Pd- or Ru-catalyzed C–H bond arylation at the ortho position of the aryl unit of 2-arylpyrazines.  The reaction proceeds with complete regioselectivity using phosphine-free Pd(OAc)2or [RuCl2(p-cymene]2, this reaction is not sensitive to the pyrazine substitution. By selecting the proper catalytic system, a wide variety of electron-rich and -poor (hetero)aryl bromides, including bromopyridine derivatives, has been successfully employed.In the last part, we explore new complex of iridium (III) cationic cyclometallized type 2-phenylimidazo [1,2-a] pyridine for the arylationof the C-H bond palladocatalyzed,The reaction is regioselective at the C3 position of the cyclometallic ligand. In addition, an example of π-extension using 1-bromo-2-iodobenzene has been demonstrated.