Transmetalation of a dodecahedral Na9 aggregate-based polymer: a facile route to water stable Cu(II) coordination networks

A variety of network structures have been prepared by transmetalation of a polymer Na3[Na9(Cbdcp)6(H2O)18] n (1) (Cbdcp = N-(4-carboxybenzyl)-(3,5-dicarboxyl)pyridinium) containing dodecahedral Na9 aggregate secondary building units with Cu(II) by modulating the temperature, solvent, and pH. These complexes include a large, zwitterionic hexa-cuprometallocycle [Cu6(Cbdcp)6(H2O)18] (2) formed in H2O at room temperature, two three-dimensional polymers [Cu3(Cbdcp)2(OH)2(H2O)2]n (3) and [Cu3(Cbdcp)2(OH)2]2H2O n (4) isolated from H2O and DMF/H2O at 135C, and a mononuclear complex [Cu(HCbdcp)2(H2O)3]H2O (5) from H2O at 100C and pH = 6. All the complexes are robust and water stable. The crystal framework of macrocycle 2 is stable up to 100C under vacuum and selectively adsorbs CO2.