Discuss the synthesis and formation of a rotaxane. Your discussion should include:i$.)$ An example from the literature of a rotaxane ii$.)$ The different supramolecular approaches taken to assemble rotaxanes iii$)$iii$.$ Analysis of rotaxanes $.$ iv $)$ How supramolecular interactions have been utilised towards the engineering of so called nano$-$machines and how they can be triggered.