A giant coordination cage based on sulfonylcalix[4]arenes

A strategy for building coordination cages by a [6 + 8] condensation of MII4-calix SBUs and rigid ancillary ligands was successfully applied to a cobalt–sulfonylcalix[4]arene system. A giant cage obtained with BTE ligands has an overall periphery diameter of 5.0 nm and an internal spherical cavity of 2.3 nm.