1,2-Diacetyl-4-phenyl-1,2,4-triazolidine-3,5-dione

The title crystal, C₁₂H₁₁N₃O₄, contains three essentially identical molecules in the asymmetric unit. The triazole rings in the three independent molecules are planar within 0.014 Å. The N atom containing the phenyl substituent is trigonal, the sum of the three bond angles being 359.5°. The other two N atoms are slightly pyramidal, the sum of the three bond angles being 346°. The two acetyl groups are twisted out of the plane of the triazole ring by an average of 33°, and are trans to each other.