Helical tubuland inclusion crystals

Compounds 87-89 containing gem-substituents at each of the 2- and 6-positions adopt a noticeably twisted chair-chair conformation as found by X-ray crystal structure analysis (66-69). The crystal structure of compound 89 belongs to a new family of helical tubuland inclusion crystals, the shape and the capacity of whose guest cavity in the crystal have been analyzed in detail (69). 

Discovery of the inclusion properties of many channel-type compounds was mainly made by chance. The creation of crystal lattices with tailor-made properties or even the fine tuning of properties of known crystal architectures represent significant challenges for materials chemists. Worth mentioning here is a large family of alicyclic diols, called helical tubulands. These com-... 

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