ACTA CRYSTALLOGRAPHICA SECTION E-CRYSTALLOGRAPHIC COMMUNICATIONS, vol.61, 2005 (SCI-Expanded)
LThe molecule of the title compound, C19H20F3N3O5, at 150 K, is nearly planar and exists in the keto-amine (N-H---O) tautomeric form, with a strong intramolecular hydrogen bond of 2.585 (2) angstrom between the O and N atoms. The configuration around the azo -N=N- double bond is trans, as found for other diazene derivatives, and the dihedral angle between the planes of the two aromatic rings is 7.81 (4)degrees.