In a recent paper Gao et al. has published the synthesis and conformational studies of a β-CD trimer in which each CD group is connected to one of bridging arms of a planar triphenylbenzene core. The compound was synthesized through a CuAAC click reaction and the self-inclusion and dissociation was studied.
The structural change of a β-CD triplet bridging with a planar tri-CD in solutions was investigated, and one of the three CD units is demonstrated to be self-included in water by NMR. The organic solvent DMSO was found to drive the dissociation of self-inclusion completely and the conformation transformation during dissociation of self- inclusion in mixture DMSO/H2O solutions was increased with the volume ratio of the organic solvent. The dependence of the self-inclusion state against heating or acidification is identified to be difficult in destroying the self-inclusion but can make the part of inclusion more or less deep inside or getting outside. Competitive guest molecules like some adamantane derivatives, which have additional interaction with the CD unit, are able to help to dissociate the self-inclusion in some extent.
Gao, B., Wang, G., Li, B., & Wu, L. (2020). Self-Inclusion and Dissociation of a Bridging β-Cyclodextrin Triplet. ACS Omega, 5(14), 8127–8136. doi:10.1021/acsomega.0c00363