(E,Z)-1-(4-Chlorophenyl)-5-phenyl-5-(phenylsulfanyl)penta-2,4-dien-1-one

The penta-2,4-dien-1-one fragment of the title compound, C23H17ClOS, is twisted by 20.0 (3)°, as measured by the dihedral angle between the planes of the carbonyl group and its attached C atom and the distant C=C double bond and its attached C atom. The 4-chlorophenyl group forms a dihedral angle of 4.0 (3)° with the adjacent carbonyl group. Conjugation between the phenyl ring and the C=C double bond is absent; the dihedral angle between the phenyl ring and the C—C=C fragment is 34.3 (2)°. In the crystal, molecules are linked via C—H⋯O hydrogen bonds, forming chains parallel to the b-axis direction.

The penta-2,4-dien-1-one fragment of the title compound, C 23 H 17 ClOS, is twisted by 20.0 (3) , as measured by the dihedral angle between the planes of the carbonyl group and its attached C atom and the distant C C double bond and its attached C atom. The 4-chlorophenyl group forms a dihedral angle of 4.0 (3) with the adjacent carbonyl group. Conjugation between the phenyl ring and the C C double bond is absent; the dihedral angle between the phenyl ring and the C-C C fragment is 34.3 (2) . In the crystal, molecules are linked via C-HÁ Á ÁO hydrogen bonds, forming chains parallel to the b-axis direction.   Table 1 Hydrogen-bond geometry (Å , ).
Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: LD2112).
The molecules are linked in the crystal via C7-H7A···O bonds into chains parallel to the crystallographic b axis. It is worth mentioning that the C-H···O bonds which involve the hydrogen atom at o position of phenyl ring are typical for 1,5-diarylsubstituted penten-yn-ones (Golovanov, et al., 2013).

Refinement
All non-H atoms were refined anisotropically. Hydrogen atoms were positioned geometrically and refined isotropically being constrained to ride on their adjacent carbon atoms with U iso (H) = 1.2U eq (C).  The molecular structure of the title compound. Displacement ellipsoids are drawn at 50% probability level.  The C-H···O bonded chain viewed down the a axis. Dashed lines indicate hydrogen bonds.

Special details
Experimental. IR (KBr), ν/cm -1 : 3051, 1648, 1589, 1573, 1559, 1481, 1441, 1397, 1356, 1333, 1272, 1225, 1176, 1091, 1025, 1009, 939. 1  Refinement. Refinement of F 2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F 2 , conventional R-factors R are based on F, with F set to zero for negative F 2 . The threshold expression of F 2 > σ(F 2 ) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F 2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.