Naphthalene derivatives peri-substituted by group 13 elements as polyfunctional Lewis acids

This research is concerned with the chemistry of polyfunctional Lewis acids containing group 13 elements and the use of such compounds in new domains of applications. A large majority of the polyfunctional Lewis acids studied so far are polytopic anion receptors that contain tin or mercury as electrophilic elements. Unfortunately, however, these compounds contain Lewis acidic elements that are weak and toxic. Thus, the preparation of group 13 polyfunctional Lewis acids has been considered, and recent studies have already demonstrated the high potential of such species in anion recognition and organometallic catalysis. The primary goal of this research has been concerned with the reduction chemistry of boron bidentate Lewis acids. These studies have focused on the isolation of radicalar complexes that feature boron-boron one-electron a bonds. As part of this work, several 1,8-bis(boryl)naphthalene derivatives were synthesized. Their reduction was studied by cyclic voltammetry. Chemically and electrochemically generated radical anion solutions were characterized by EPR spectroscopy. These studies were supplemented by DFT calculations, which substantiate the formation of a boron-boron one-electron a bond. The second part of this work involves the incorporation of heavier group 13 elements into bifunctional and trifunctional Lewis acids. Results gathered so far have shown that a variety of receptor architectures can be readily accessed. In particular, a trifunctional gallium Lewis acid has been prepared. Anion binding experiments were also carried out.