Molecular guest-shuttling: transitioning from thread-based to threadless systems

Despite extensive studies on supramolecular coordination complexes (SCCs), the field of organometallic-based supramolecular entities remains relatively underexplored. The challenges in this area arise from the air-sensitivity of organometallic compounds and the limited reversibility of metal–carbon bonds. However, a recent report by Peris and co-workers describes the development of an air-stable, self-assembled, and discrete tetrairidium molecular box featuring an elongated Janus-type dicarbene ligand. This molecular box not only demonstrates versatile guest-binding properties, but also exhibits a rare type of ‘shuttle’-like sliding motion of guests within it.