Diethyl N,N '-(naphthalene-1,8-diyl)dioxamate

The reaction of ethyloxalyl chloride and naphthalene-1,8-diamine in refluxi ng tetrahydrofuran yielded the title compound, C18H18N2O6 Thr crystal struc ture analysis reveals a molecule with one oxamate substituent nearly coplan ar with the aromatic naphthalene system, while the second is strongly twist ed with respect to the naphthalene system. Three strong intramolecular hydr ogen bonds are observed, one in each oxamic acid ethyl ester group and one linking the two substituents. Symmetry-related molecules are connected by a fourth intermolecular hydrogen bond.