Two isomorphic organically templated zinc/cobalt oxalates, (dmdabco)[Zn2(C2O4)3]·4H2O (1), and (dmdabco)[Co2(C2O4)3]·4H2O (2) (C2O42− = oxalate; dmdabco = N,N′-dimethyl-1,4-diazabicyclo[2,2,2]octane), have been prepared under solvothermal conditions and characterized by X-ray structural analyses. The dmdabco2+templating agent was derived from simplein situN-alkylation between methanol and 1,4-diazabicyclo[2,2,2]octane (dabco). Distinct from conventionalEschweiler-Clarkemethylation containing excess formic acid and formaldehyde, such one-step methylation from methanol molecules is convenient. Both1and2exhibit a uninodal 3-connected 3-D interrupted open-framework, in which oxalate ligands havein-planeandout-of-planeconnection modes. [ABSTRACT FROM AUTHOR]