The 2011 Diamond Annual Review, which highlights some of the world-class research recently undertaken at Diamond Light Source is now available from their website. The report includes a contribution from Prof. Paul Beer covering some of the fascinating interlocked structures determined from data collected using the Small Molecule Beamline, I19, as part of the Oxford Block Allocation Group (BAG). Highlights of their work include a novel halogen bonded rotaxane and the first reported crystal structure of a “handcuff catenane”.
Presented by: Matthew J. Langton, Jonathan D. Matichak & Dr. Amber L. Thompson
Research Leader: Prof. Harry L. Anderson
Published: Chemical Science (cover article)
Fully π-conjugated porphyrin oligomers exhibit remarkable properties such as ultrafast energy migration, strong two-photon absorption and wire-like charge transport. The possibility to encapsulate them by rotaxane formation may provide valuable control over their properties by offering a unique approach to engineering intermolecular interactions. An active-template Cu-mediated Glaser coupling provides an efficient route to these structures. Data from crystals of this rotaxane were collected in-house. The porphyrin dimer is slightly twisted and non-linear, contrasting with previously reported structures which possess an inversion centre (and are thus rigorously planar). The phenanthroline units of the threaded macrocycle form tightly packed π-stacks in the crystal.