Dave Evans Research
I currently have three (3) projects in progress, to varying degrees depending mainly on student interest and funding availability:
- The area of ionic liquids is receiving wider attention as the field becomes known by mmore and more chemists in a wide variety of areas raning from electro-, inorganic, industrial and organic chemists. The main class of compounds are the N,N’-dialkylimidazolium ions. We are involved in both the synthesis of novel compounds within this general class and the exploration of the potential use as “green” solvents.
- Another project is the synthesis of polypyridyl amine ligands. This project has ultimate applications in both first row transition metal complexes, as well as the larger metals. An area of exploration will be in the chemistry of Ruthenium(II) complexes for their photochemical properties. In addition, Palladium(II) polymeric complexes are conceivable that may possess conducting properties. Molecular modeling calculations have shown some intriguing possibilities on both fronts.
- The synthesis of highly electron-deficient nitrogen heterocycles is an area that has not received a lot of attention in past years. When the first simple 1,2,4-triazine N-oxides were synthesized, many experts in the field anticipated that they would not be stable. However, not only are they stable species, but they also have a very interesting chemistry. In conjunction with molecular orbital predictions, we hope to push the level of "acceptable" electron-deficiency to its limits. Much fundamental chemistry of 1,2,4-triazines is as of yet unexplored. For example, the first reaction shown below indicates the formation of the 6-substituted product. Current resonance theory would indicate this to be the predominate product. However, molecular orbital calculations (utilizing the CAChe system) clearly shows that the 5-position on the 3-methoxy-1,2,4-triazine is the preferred site of electrophilic substitution. These discrepancies occur with increasing frequency throughout this chemistry. It will be edifying to determine which theory best predicts their chemistry. These compounds have been utilized as intermediates for difficult-to-obtain pyridines (via Diels-Alder chemistry) and an expansion of our knowledge of their chemistry should provide ready access to potentially important pyridines, as well as the potential use of the triazines themselves.
Brett K. Simpson