Complexation of I42? and I82? by protonated azacyclophanes

A macrocyclic azacyclophane (1) includes two iodide anions within its macrocyclic cavity. The resulting 1·2I− complex (in two polymorphic modifications) sandwiches I2 in the solid state to give a ‘complex of complexes’ effectively stabilising the rare I42− anion. A third crystal form contains a macrocycle incorporating both a discrete I− anion and the tail of the polymeric I82− in a closely related fashion.