Note that 50% of the DNP sites are occupied by CBPQT
4+ in the infinite-chain
lattice superstructures of these pseudorotaxanes, although an odd number of recognition sites on the oligomeric threads prevents this 2:1 stoichiometry from
manifesting itself in any individual complex. Whereas 5NPE & [CBPQT
4+ ] n
b
a
Fig. 3 Structural formulas and X-ray single-crystal superstructures of the apparently infinite
polypseudorotaxanes formed between CBPQT
4+ and 5NPE (a) or 5NP (b)
a
b
c
Fig. 4 Representations of the vacancies that occur in pseudorotaxanes formed between
pentameric DNP threads and CBPQT
4+ . In 5NPE & CBPQT
4+ , one in six DNP sites are vacant,
with a preference for alongside DNP units (a) over encircled DNP units (b) as the vacated site.
5NP & CBPQT
4+ can maintain a continuous D–A stack by equal co-crystallization of three- and
four-component pseudorotaxanes, leaving one in five polyether loops vacant (c)
Mechanically Interlaced and Interlocked Donor–Acceptor Foldamers
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