Making Molecular Borromean Rings. A Gram-Scale Synthetic Procedure for the Undergraduate Organic Lab

Abstract

Borromean rings (BRs) have long fascinated scholars of all disciplines for their wide cultural appeal and unique topology. Undergraduate students are no exception and so we have modified our published experimental procedure for the synthesis of molecular BRs to turn it into a lab instruction experiment suitable for undergraduate students to pursue in an organic chemistry laboratory course. Herein, we describe a procedure that requires seven 4-hour blocks of time to allow an undergraduate student to prepare the molecular BRs on a gram-scale in 90% yield. Just as important as engaging students in the BRs is the fact that the making of the molecular BRs incorporates several important, yet nonetheless overlooked, areas of chemistry. They include synthetic organic, physical organic, inorganic and metallo-organic chemistry, supramolecular, and dynamic covalent chemistry, all packaged up under the same umbrella in one project.