The molecular components 1 and 2 together with Cu(I) self-assemble to form a metalcontaining pseudorotaxane of composition [Cu(1)(2)]+ (note that the counter-anion has been excluded).

a) Sketch the metal-containing pseudorotaxane [Cu(1)(2)]+ paying particular attention to the coordination environment of the Cu(I) centre. Why is this assembly described as a pseudorotaxane rather than a rotaxane? b) This metal-containing pseudorotaxane has been shown to undergo electrochemicallydriven molecular motion based on the redox couple between Cu(I) and Cu(II). Explain how and why the molecular motion occurs. c) Suggest a variation of 2 with suitable functional groups that would allow the pseudorotaxane to be converted to a catenane.

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