FRAMEWORK COORDINATION CHEMISTRY - GENERALIZED ENTRY INTO A NEW CLASS OF SUPRAMOLECULAR COMPOUNDS EXEMPLIFIED BY THE STRUCTURES OF [MN2(EBPY)3(NO3)4]N[WHERE EBPY=N,N'-ETHYLENEBIS(2-PYRIDONE)] AND [ER2(EBPYRR)3(NO3)6]N[WHERE EBPYRR=N,N'-ETHYLENEBIS(2-PYRROLIDONE)]

The ethylene-bridged bis(2-pyridone) ligand N,N'-ethylenebis(2-pyridone) and its bis(2-pyrrolidone) analogue react with manganese(II) nitrate and erbium(III) nitrate to form polymers containing 36-membered or 54-membered metallomacrocyclic rings, respectively; the 36-membered rings are linked to form a chain polymer and the 54-membered form contiguous two-dimensional sheets.