Song-Toan Pham

Both symmetrical and unsymmetrical cyclophanes containing disilane units, tetrasila[2.2]cyclophanes 1–9, were synthesized. The syn and anti conformations and the kinetics of inversion between two anti-isomers were investigated by X-ray diffraction and variable-temperature NMR analysis, respectively. The flipping motion of two aromatic rings was affected by the bulkiness of the aromatic moiety (1 vs 6), the phase (solid vs solution), and the inclusion by host molecules (1 vs 1?[Ag L]2+).