Torus knots are assembled in a contra-helical tubular manner by coaxially nesting a small multistranded helix within a larger reverse helix. This approach enables the near-quantitative one-step syntheses of four iron(II)-templated trefoil knots. The spin-crossover properties of the iron(II) centres in the knots are tuneable by altering the intramolecular strain.
- Lin Wu
- Min Tang
- Zhichang Liu