UC San Diego

Carbenes play a prominent role as ligands for transition metal catalysts. This is mainly due to their strong s- donor properties and the robustness of the corresponding complexes. These two features result from the presence of the electropositive carbon center and the strength of the carbon-metal bond. Therefore, other types of carbon-based L ligands are highly desirable. This manuscript describes the design and synthesis of a variety of new carbenes belonging to the family of mesoionic carbenes. It will be shown that the stability of mesoionic carbenes depends on the nature of the heteroatoms of their aromatic system. We will also demonstrate that simple alkynes can be used as mesoionic carbene ligand equivalents of various ring sizes towards various transition metals. Moreover, the use of one simple unsaturated compound for the activation of small molecules and the cleavage of enthalpically strong bonds will be discussed