New Concepts in Lewis Acidity, Catalysis, and Polymer Science: Functional Main Group Cages

The elements of the periodic table combine with one another to give molecules which are the building blocks of our material world. Defining the shape, size, and properties of these blocks is an essential first step towards creating new useful materials such as plastics, catalysts, and fuels. Chemists have traditionally focused on the organic elements (C, N, H, O) as a source of useful molecules, in part due to the historic reliance upon organic element-rich feedstocks (e.g. petroleum and natural gas). The remaining 77 or so stable elements of the periodic table have received less attention by comparison, despite the fact that many of them are very abundant on earth (e.g. silicon). With the aid of this Discovery Grant, the Chitnis group will begin operations at Dalhousie University in July 2018 and establish a program of extracting exciting functional properties from the abundant and often benign elements of the p-block of the periodic table. One targeted property will be selective binding and modification of small molecules that are found in industrial emissions or in natural or anthropogenic toxins. To achieve this, the group will make liquids that contain dissolved inorganic cages, making them porous (like a sponge), and then enhance the binding abilities (Lewis acidity) of the cages. Depending on the size of the cages in the liquid, these porous liquids will bind different molecules. We will also discover new catalysts for safer and more efficient manufacturing of commodity chemicals and pharmaceuticals. For this purpose, we will focus on the chemistry of bismuth cages as this element is inexpensive and nontoxic. Lastly we will link together inorganic cage molecules into polymers that could one day be incorporated into electronic devices as smart responsive materials. In particular we will target charged polymers which will exhibit good water solubility and conductivity, making them potentially useful in both biological and electronic applications. In summary our research will exert control over the shape, size and electronic properties of inorganic cages to devise useful chemical systems for incorporation into technologies of daily relevance.This research program will also train undergraduate and graduate students to be chemists who can independently conceive, execute, and communicate scientific projects, using state-of-the-art equipment. The skills developed through this training are essential components of a broad range of careers in government, industry or academia. The creation of a scientifically-literate workforce is essential for sustaining the pace of innovation needed for Canada to remain a technologically advanced nation.