Chemical Science Blog

Boronic esters have been used by US scientists to transform the triphenylene core in discotic liquid crystals (DLCs) from electron-rich to electron-deficient.

DLCs are used in electronic devices such as light emitting diodes. They need an electron-rich donor and an electron-poor acceptor. Current electron-poor acceptors have shortcomings including the fact that they can’t form columnar mesophases.

The team incorporated a boronic ester into the triphenylene core, which makes it an electron-poor acceptor and they were able to achieve broad mesophase temperature ranges.

Boronic Esters: A Simple Route to Discotic Liquid Crystals that Are Electron Deficient
Benjamin King and Luke Andrew Tatum
DOI: 10.1039/C2SC20128C

Scientists in Canada have studied the synthetic scope of a new system of [2]rotaxane molecular shuttles based on a templating motif involving a benzimidazolium–crown ether recognition pair.

The template allows an array of molecular shuttles containing macrocyclic crown ethers of varying size and shape to be prepared.

The study also provides the beginnings of a property–structure relationship for molecular shuttling in this rigid, compact [2]rotaxane system. This could aid in the future design of [2]rotaxane molecular shuttles for incorporation into materials such as metal–organic frameworks.

Bis(benzimidazolium) axles and crown ether wheels: a versatile templating pair for the formation of [2]rotaxane molecular shuttles
Stephen J. Loeb, Kelong Zhu, V. Nicholas Vukotic and Nadim Noujeim
DOI: 10.1039/C2SC20986A