Design and Synthesis of Functional Molecular Architecture

Abstract

The central theme of the research conducted by the Diederich group is the creation of functional molecular architecture by design and advanced synthesis. Function is explored through interdisciplinary study, wherein national and international collaborations provide fertile grounds. Four areas of research are pursued: (i) In covalent fullerene chemistry, regio- and stereoselective templated synthesis protocols are developed to prepare three-dimensional building blocks for supramolecular construction and advanced materials such as electrochemical ion sensors. (ii) Advanced materials are also targeted by acetylenic scaffolding. Macrocyclic scaffolds of interest include perethynylated expanded radialenes featuring large π-conjugated all-carbon cores. Acyclic scaffolds such as monodisperse poly(triacetylene) (PTA)oligomers, with linear, π-conjugated allcarbon backbones expanding up to 18 nm length, are also actively investigated. Arylated tetraethynylethenes undergo photochemical cis→ trans and trans→ cis isomerization without competing thermal isomerization pathways – promising applications of these materials are foreseen in optical switching and memory storage devices. (iii) In supramolecular chemistry, dynamic receptors are developed with the potential to function as 'molecular grippers' on the single molecule level. Dendritic porphyrins are efficient models of hemoglobin and myoglobin and bind O₂ strongly and reversibly. They are also ideal model systems to explore the influence of the protein shell on the redox potential ofthe Fe^III/II couple in electron transfer proteins such as the cytochromes. (iv) Finally, the detailed understanding of molecular recognition principles generated in the studies with artificial receptors provides the basis for a modern medicinal chemistry program aimed at the structure-based de novo design of nonpeptidic enzyme inhibitors.