Synthesis and Structural Characterization of a Cyclen-Derived Molecular Cage.

Reaction of a tetrafunctionalized cyclen derivative containing four aldehyde groups with an appropriate diamine followed by reduction and demetalation highly efficiently affords a bis(cyclen)-derived molecular cage. Potentiometric investigations show that this compound forms dimetallic complexes with copper(II), with the two metal ions selectively coordinated to the cyclen units. X-ray crystallography indicates that these complexes could give rise to new cascade complexes after incorporation of anions between the metal centers.