In the last decade, transitional metal catalyzed (Pd, Rh, Co, Ru, Ir, Mn, Cu, Ni) C-H activation has become one of the most extensively studied research topic in synthetic organic chemistry. With this methodology, aromatic C-H bonds can be easily substituted with different functional groups, without any previous functionalization of starting substance. In aromatic compounds, there are many H atom in similar chemical environment, which can raise problems in regioselectivity for first sight. However, the introduction of a directing group (DG) into the aromatic core allows selective metalation in <i>ortho</i> position. In our research, we focused on the late-stage introduction of fluorine containing functionalities, in order to their effect on lipophilicity and metabolic stability. Due to the presence of fluorine atoms the electronic properties of the molecules also change and allow further reactions on multifunctionalized aromatic cores. We present a simple and robust catalytic method for efficient and selective trifluoroethylation and fluoroalkenylation reaction of (hetero)aromatic compounds using highly active trifluoroethyl(mesityl)iodonium and related hypervalent iodine salts. The utilization of hypervalent reagents opens new synthetic possibilities and allows mild reaction conditions. Besides the scope and limitations, the mechanism has been investigated. We aimed to settle a comprehensive theory, which includes numerous diverse experimental results combined with DFT calculations. Building a multiparameter field tool allows to understand complex steric and electronic problems and achieve a predictable system in C-H activation.

Mild and efficient palladium-catalyzed fluoroalkylation and fluoroalkenylation of (hetero)aromatic systems by directed ortho-C-H activation

2019 Spring National Meeting

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.