Multimodal Molecular Motion in the Rotaxanes and Catenanes Incorporating Flexible Calix[n]phyrin Stations.

The synthesis of [2]rotaxanes stoppered with one or two dipyrromethane groups has opened a route for the construction of mechanically interlocked molecules incorporating various porphyrinoid stations. The exploitation of those precursors allowed the creation of [3]rotaxanes and [2]catenanes based on the calix[4]phyrin motif, presenting intriguing molecular dynamics. The intrinsic flexibility of the porphyrinoid allowed the introduction of a new type of molecular motion within the rotaxanes, termed fluttering.

The Intracavity Extension of 28-Hetero-2,7-naphthiporphyrins in Reactions with Alkylamines.

The 28-hetero-2,7-naphthiporphyrins reacted with triethylamine and diethylamine to form nonaromatic intracavity-extended macrocycles incorporating naphthodihydro-2-pyran, naphthotetrahydropyridine, and naphthopyrrolotetrahydro-1-azepine moieties. The new macrocycles were characterized in solution by means of NMR and UV-vis spectroscopy and in the solid state by XRD.

POSSaxanes: active-template synthesis of organic-inorganic rotaxanes incorporating cubic silsesquioxane stoppers.

The CuAAC active-template approach was exploited to construct rotaxanes incorporating cage-like silsesquioxane stoppers, namely, POSSaxanes. The compounds were characterized in the solution and solid state, providing the unprecedented molecular structures of POSS-incorporating rotaxanes.