Rodolfo A. Martinez

S-Phenyl N,N′-dimethyl-13C2-thio­oxamate: a by-product in the synthesis of ethyl N,N′-dimethyl-13C2-oxamate

The title compound, C10H11NO2S, was crystallized from solution as a by-product during the synthesis of ethyl dimethyl oxamate. It should be noted that Nair & Sheeba [J. Org. Chem. (1999). 64, 6898–6900] also synthesized an oxamate as a by-product during the transformation of acetoacetamides to cyclic compounds that was modified later to the synthesis of oxamates as primary products. NMR analysis of the compound did not provide a good basis for structural elucidation as it gave no indication of the presence of any heteroatom directly attached to the phenyl ring. X-ray single-crystal analysis revealed the direct attachment of an S atom to the ipso-carbon of the phenyl ring. The resultant structure is a thioxadoxamate. The two carbonyl groups are not coplanar.