Chemists construct a symmetrical nortricyclene

Apart from the grunt work and smells that come with being a chemist, there’s the artistry and an appreciation of the synthetic achievements in which elements are coupled together in beautiful or unexpected ways. In a recent example, a team led by Volodymyr Kozel and Günter Haufe of the University of Münster have synthesized a tricyclic triol that represents the smallest known molecule to display threefold symmetry in a chiral polycyclic compound (Angew. Chem. Int. Ed. 2017, DOI: 10.1002/anie.201709279). Controlling the symmetry of molecules is often important for developing pharmaceuticals and self-assembled macromolecular materials. But designing for symmetry isn’t easy: Molecules with a twofold plane of symmetry are well established, and threefold symmetry is common for molecules like trisubstituted benzenes and triazines. But refining synthetic approaches to achieve threefold symmetry found in more structurally diverse molecules is still a work in progress. Haufe’s group has added to prior work on symmetric tricyclic molecules by designing a synthetic approach to functionalize a bicyclic alkoxy-substituted norbornadiene, which leads to a racemic mixture of the previously unknown C3-symmetric nortricyclene-3,5,7-triol (shown). With an enantiomeric resolution procedure, the team obtained pure enantiomers of the nortricyclene on a gram scale. In a collaboration with Merck KGaA researchers, the Münster team is using the new molecule to prepare dopants for liquid crystals with potential applications in integrated circuits.