Synthesis of Crown Ether Rotaxanes

Abstract

By Natalie Trent, Chemistry

Advisor: David Smithrud

Presentation ID: PM_D24

Abstract: Heavy metal cations are harmful to the human body as they turn into free radicals and oxidize cells throughout. Oxidized cells increase blood acidity and raise lactic acid levels, causing numerous maladies such as cancer. Consequently, there is demand for molecules that can sense heavy metal cations in the environment, and possibly trap and remove them. A new class of molecules called crown ether rotaxanes can selectively bind metal cations. A rotaxane consists of a rod shaped molecule (axle) that passes through a circular molecule (wheel) with blocking groups attached to the axles ends to prevent the wheel from falling off. One blocking group is a crown ether that helps to provide cation selectivity. My research project is to derivatize the wheel to enhance the selectivity for heavy metal cations. Synthesis of the rotaxane requires a multistep approach. 1H NMR analyses were used to assess the structures of intermediate components and final rotaxane. The ability to bind metal cations will be investigated using transfer assays.