A polyaromatic nanocapsule as a sucrose receptor in water.

Selective recognition of saccharides by artificial receptors in water is a challenging goal due to their strong hydrophilicities and complex molecular structures with subtle regio- and stereochemical differences. We report the selective and efficient encapsulation of d-sucrose within a coordination-driven molecular capsule from natural saccharide mixtures in water (~100% selectivity, >85% yield, and ~103 M-1 binding constant). Unlike previous artificial receptors and natural receptors that rely on multiple hydrogen-bonding interactions, theoretical calculations and control experiments indicate that the observed unique selectivity arises from multiple CH-π interactions between the sucrose hydrocarbon backbone and the shape-complementary polyaromatic cavity (~1 nm in diameter) of the capsule.