Thomas L. Lemke

Crystal and molecular structure of (Z)-5,6-dihydro-8(7H)quinolinone thiosemicarbazone

The crystal structure of (Z)-5,6-dihydro-8(7H)quinolinone thiosemicarbazone has been determined by X-ray diffraction techniques in order to confirm the identity of this analog of the antineoplastic agent 2-formylpyridine thiosemicarbazone and to determine the nature of the hydrogen bonding in the solid state. The crystals are pale yellow, space groupP21/n, witha = 7.682(3),b = 10.168(8),c = 14.795(5) Å, β = 103.11(4) °, andZ = 4. The structure was solved by direct methods and refined to a finalR value of 0.017. The molecule is quite planar, with the obvious exception of the central saturated carbon, and this, along with a short C-C bond at the point of attachment of the side chain, appears to be due to an interaction with the pyridyl ring. The molecules are arranged in pairs held together by mutual intermolecular S⋯N hydrogen bonds. There is also an extensive system of intramolecular N⋯N hydrogen bonds.