화학공학소재연구정보센터
Journal of the American Chemical Society, Vol.137, No.33, 10536-10546, 2015
A Remarkably Complex Supramolecular Hydrogen-Bonded Decameric Capsule Formed from an Enantiopure C-2-Symmetric Monomer by Solvent-Responsive Aggregation
The formation of an unprecedented decameric capsule in carbon disulfide, held together by the combination of double and triple hydrogen bonds between isocytosine units embedded in an enantiomerically pure bicyclic framework is reported. The aggregation occurs via symmetry breaking of the enantiopure intrinsically C-2-symmetric monomer brought about by solvent, induced tautomerization of the hydrogen-bonding unit. We show that the topology of the aggregate is responsive to the solvent in which the assembly takes place. In this study we demonstrate that in carbon disulfide the chiral decameric cavity aggregate consisting of three forms of the same monomer, differing in their hydrogen bonding to each other is selectively formed, representing a tube-like structure capped with two C-2-symmetric monomers. The large cylindrical cavity produced selectively accommodates one partially solvated C-60 molecule, and molecular dynamic simulations revealed the special role of the solvent in the inclusion mechanism. The strategy described herein represents the first step toward the creation of a new class of hydrogen-bonded tubular objects from only one small symmetric building block by solvent-responsive aggregation.