Design and synthesis of bimetallic complexes containing Fe2+, V2+, and Cr2+

The synthesis of novel bimetallic complexes containing Fe²⁺, V²⁺, and Cr²⁺ is discussed. Compounds with a bimetallic structure, such as dirhodium tetraacetate, are very efficient catalysts for functionalizing C-H bonds. However, due to the high cost of Rhodium, structurally analogous catalysts using cheaper first row transition metals are of interest. Each metal was reduced to an oxidation state of two before reaction with the multi-dentate ligand ESP (ESP=α, α, α’, α’-tetramethyl-1,3-benzenedipropanoate). The bidentate metal core of each complex is bridged by two carboxylate groups from the ESP ligand. All reactions were done under inert conditions. The structures were characterized by NMR Spectroscopy, MALDI-TOF Mass Spectrometry, and X-ray diffraction. These newly designed complexes were screened to determine if they mimic rhodium’s catalytic activity in C-H functionalization. Their greatest importance is to improve the efficiency of reactions to functionalize organic substrates and decrease the cost of performing them.