Unexpected formation of a tubular architecture by optically active pure organic calixsalen

Abstract

Herein, an unusual tubular formation of a supramolecular organic framework by optically active macrocyclic calixsalen is shown via single crystal X-ray diffraction. The monomers are either bound by hydrogen bonds between OH groups in the lower rim of the macrocycle to form an hourglass structure or form a capsule with the calixsalens arranged in a head-to-head motif.