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

Abstract

POSSaxanes, a group of hybrid organic–inorganic rotaxanes incorporating subnanometer-to-nanometer-sized cage-like silsesquioxane stoppers, were synthesized by exploiting the CuAAC active template approach.

Curved Nanographenes as Stoppers in a [2]Rotaxane with Two-Photon Excited Emission

“…In fact, most examples of reported rotaxanes displayed arene (e.g., trityl-based stoppers) or alkane (e.g., functionalized with t -butyl groups) motifs or combinations of them as stoppers, with no properties or functions other than their bulkiness. , There are, however, exceptions, and some early designs already incorporated stopper units with different properties that could play a functional role such as fullerenes or porphyrins, which have continued to be used over the years . Since then, an increasingly amount of potentially functional structures such as peptides or proteins, nanoparticles or inorganic clusters, oligonucleotides, subpthalocyanines, drugs, cyclodextrins or calixarenes, ligands, redox or photo-active groups, or radicals have been progressively incorporated as stopper units in rotaxanes. In this sense, we can highlight functional stoppers with luminescence properties .…”

An Inorganic Click Reaction for the Synthesis of Interlocked Molecules

“…[15] More recently, John and Szyszko have prepared rotaxanes containing cubic silsequioxane stoppers via the CuAAC reaction in an active-metal templating route with prefunctionalized alkynes and azides. [16] The relative rarity of "inorganic rotaxanes" is due to the dearth of reliable methods for generating mechanically interlocked molecules containing inorganic or organometallic sub-components. This prompted us to ask whether a versatile and high-yielding synthetic protocol, akin to the CuAAC reaction, could be used to access supramolecular compounds with inorganic functionalities.…”