CrownCast-3

CrownCast-3 Architect: Daniel Kennedy/Hannah Mbatia Year Reported: 2010 Journal Reference: Eur. J. Inorg. Chem. 2010, 5069

CrownCast-3 is a Cast-type photocage that was developed by Hannah Mbatia with the assistance of Daniel Kennedy and Casey Camire. The receptor is a NS₂O₂ macrocyclic ligand. CrownCast-3 binds an array of soft M²⁺ ions with a preference for Hg²⁺ in aqueous solution. Photolysis is intended to introduce of an electron withdrawing carbonyl group para to the aniline that decreases the electron density on nitrogen atom and therefore the M²⁺ affinity; however, very minimal changes are observed with in the affinity with Hg²⁺ after photolysis. The lack of metal ion release is attributed to the stability of the S-Hg-S binding motif.

X-ray Structure of CrownCast-3 model ligand with Hg2+