摘要:
The title carbazone, C15H12F2N4O (I), was found to be an intermolecularly hydrogen-bonded centrosymmetric dimer. [For a discussion of CAS/IUPAC nomenclature of carbazones see Grasselli and Weast (1989), In Handbook of Data on Organic Compounds, 2nd edition, Vol. I, Introduction, 190, 252, Florida: CRC Press.] This is in contrast to the only other reported X-ray structure of a related carbazone, which was a non-centrosymmetric infinite hydrogen-bonded polymeric structure, The monomer unit of compound (I) is neither planar nor symmetrical. One amidic H atom is anti to the carbonyl O atom while the other is syn, The syn amidic H atom and the carbonyl O atom form strong hydrogen bonds with the respective atoms of a second molecule to produce an eight-membered ring which links the two monomeric units. The intermolecular N-H ... O hydrogen-bond distances are 2.01 (2) Angstrom for H ... O and 2.873 (3) Angstrom for N ... O, and the N-H ... O angle is 172(2)degrees. The anti amidic H atom of compound (I) is not involved in hydrogen bonding.