Metallacarbatrane, Hydride, Fluoride, and Metal-Metal Bonded Compounds of the Main Group Elements: Synthesis and Applications

Columbia University, New York NY

Investigators

Abstract

In this project funded by the Chemical Synthesis Program of the Chemistry Division, Professor Gerard Parkin of the Department of Chemistry at Columbia University investigates fundamental chemistry of compounds of Earth-abundant main group metals. This research is required for developing the use of such compounds as catalysts for organic transformations and for constructing new materials. Catalysts are critical for the conversion of chemical feedstocks into more useful compounds, and an important objective is to discover new catalysts that do not incorporate precious metals. Magnesium and calcium are two examples of Earth-abundant main group metals that are investigated. The investigation focuses on the use of multidentate ligands to enforce well-defined coordination environments for main group elements. Specific examples of ligands that are used in this research include (i) tridentate tripodal ligands, such as tris(pyrazolyl)hydroborato and tris(2-mercaptoimidazolyl)hydroborato, and (ii) tetradentate tripodal ligands, such as tris(2 pyridylthio)methyl, while examples of target compounds include those with terminal alkyl, hydride, and fluoride ligands, and also those which feature metal?metal bonds. The research involves the use of single crystal X-ray diffraction and NMR spectroscopic methods to determine the structures of the synthesized molecules, and computational methods to analyze the bonding. An important aspect of the activities is that it involves training students to be future professionals, be it in an academic or industrial setting. As is customary for the research group, the research activities not only involve graduate and undergraduate students, but also involve high school students, thereby providing a significant STEM experience for them at a critical point in their education. In addition, the research group is also involved in performing chemistry demonstrations for children from ethnically diverse New York City public middle schools.