Chirality transcription and amplification by [2]pseudorotaxanes.

Chirality transcription and amplification by the formation of chiral [2]pseudorotaxanes by an achiral crown ether having the 2',2''-quaterphenyl group and chiral sec-ammonium ions are reported. It was revealed that the absolute configurations of the chiral sec-ammonium ions can be detected directly from the CD spectra of the chiral [2]pseudorotaxanes.

Extra large macrocycle: 40-membered macrocycle via 2:2 cyclization and its dimercury(II) complex.

A large 40-membered N(4)O(4)S(4) macrocycle (L(2)) was obtained through a 2:2 cyclization of the corresponding dithiol and dichloride as a minor product during the preparation of a 20-membered N(2)O(2)S(2) macrocycle (L(1), 1:1 cyclization product). Each macrocycle was successfully separated from the mixed products and identified. The larger macrocycle L(2) allowed the preparation of its dimercury(II) complex, adopting a one-dimensional (1D) stairway-like polymeric chain linked with the anion.