One Guest or Two? A Crystallographic and Solution Study of Guest Binding in a Cubic Coordination Cage.

ABSTRACT: A crystallographic investigation of a series of host-guest complexes in which small-molecule organic guests occupy the central cavity of an approximately cubic M₈ L₁₂ coordination cage has revealed some unexpected behaviour. Whilst some guests form 1:1 H⋅G complexes as we have seen before, an extensive family of bicyclic guests-including some substituted coumarins and various saturated analogues-form 1:2 H⋅G₂ complexes in the solid state, despite the fact that solution titrations are consistent with 1:1 complex formation, and the combined volume of the pair of guests significantly exceeds the Rebek 55±9 % packing for optimal guest binding, with packing coefficients of up to 87 %. Re-examination of solution titration data for guest binding in two cases showe

SUBMITTER: Taylor CGP 

PROVIDER: S-EPMC7079040 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature