A Star of David [2]catenane of single handedness

Abstract

<h2>Summary</h2> Prime links with multiple interlocked components feature unconditional topological chirality. Although several prime links have been constructed to date, the control of their chirality with high stereoinduction is rare. Here, we report the stereoselective synthesis of an iconic molecular <mml:math><mml:mrow><mml:mn>6</mml:mn><mml:mn>1</mml:mn><mml:mn>2</mml:mn></mml:mrow></mml:math> link (Star of David [2]catenane) comprising two triply entwined 84-membered rings. The single-handed Star of David catenane is generated from the closure of a hexameric copper(I) circular helicate by ring-closing olefin metathesis, and the topological writhe (<i>w</i> = −6) was predetermined by the configuration of the chiral ligand. Conformation of the topology was proven through NMR spectroscopy and mass spectrometry, whereas the handedness of the link was further investigated through circular dichroism. Stereoselective synthesis of molecular nanotopologies with certain topological writhe by chiral information transfer opens the way to probe the consequences and potential of topological stereochemistry in chemistry, materials, and biology.