| Institution: | 1. CEMES, Université de Toulouse, CNRS, 29, rue Jeanne Marvig, 31055 Toulouse, France;2. UPS, Institut de Chimie de Toulouse, Université de Toulouse, ICT FR 2599, 118 route de Narbonne, 31062 Toulouse, France;3. Division of Materials Science, Nara Institute of Science and Technology, 8916-5 Takayama Ikoma, Nara, Japan
NAIST-CEMES, International Collaborative Laboratory for Supraphotoactive Systems, 31055 Toulouse, France |
| Abstract: | The design and synthesis of two families of molecular-gear prototypes is reported, with the aim of assembling them into trains of gears on a surface and ultimately achieving controlled intermolecular gearing motion. These piano-stool ruthenium complexes incorporate a hydrotris(indazolyl)borate moiety as tripodal rotation axle and a pentaarylcyclopentadienyl ligand as star-shaped cogwheel, equipped with five teeth ranging from pseudo-1D aryl groups to large planar 2D paddles. A divergent synthetic approach was followed, starting from a pentakis(p-bromophenyl)cyclopentadienyl ruthenium(II) complex as key precursor or from its iodinated counterpart, obtained by copper-catalyzed aromatic Br/I exchange. Subsequent fivefold cross-coupling reactions with various partners allowed high structural diversity to be reached and yielded molecular-gear prototypes with aryl-, carbazole-, BODIPY- and porphyrin-derived teeth of increasing size and length. |
