Four metal oxalates, Hdpa⋅Cr(ox) 2 (1), (Hdpa) 2 ⋅Zn 2 (ox) 3 ⋅2H 2 O (2), Zn(H 2 O)(ox) (3), and (Hgua)(H 3 O)⋅Cd(C 2 O 4 ) 2 (4), have been synthesized under solvent-free conditions, where dpa=diisopropylamine, ox=oxalate, and gua=guanidine. These compounds have extended structures varying from 1D chain (for 1), to 2D layer (for 2 and 3), and 3D framework network (for 4). The temperature dependence of the magnetic susceptibility of compound 1 indicates the existence of antiferromagnetic interactions between the chromium ions. Upon excitation at 230nm, compound 3 exhibits an extensive luminescence with a peak centered at 501nm.