N-Benzoyl-N′-(1,10-phenanthrolin-5-yl)thiourea dichloromethane hemisolvate monohydrate

The title compound, C20H14N4OS·0.5CH2Cl2·H2O, contains 1,10-phenanthroline and benzoyl fragments that adopt cisoid and transoid conformations respectively, with respect to the S atom. In the crystal, molecules are linked by intermolecular O—H⋯O, O—H⋯N, N—H⋯O and C—H⋯O hydrogen bonds, forming chains along [011]. Weak C—H⋯π and slipped π–π stacking interactions [centroid–centroid distances = 3.715 (3), 3.684 (3) and 3.574 (2) Å] are also observed. In addition to an ordered water molecule of solvation, there is a disordered dichloromethane solvent molecule which was difficult to model correctly. The contributions to the electron density for this molecule was removed using the SQUEEZE procedure in PLATON [Spek (2009 ▶). Acta Cryst. D65, 148–155].

The phenyl and phenanthroline rings are twisted with relative to the central thiourea fragment dihedral angles of 29.46 (12)° and 74.06 (8)°, respectively. The phenyl and phenantroline rings are almost perpendicular to each other with dihedral angle of 83.15 (10)°.

Experimental
The reaction scheme involved a reaction of benzoyl chloride (8.6 mmol) with ammonium thiocyanate (8.6 mmol) in acetone.
The product, benzoyl isothiocyanate (7.7 mmol) was reacted with 1,10-phenanthrolin-5-amine (7.7 mmol) to give the title compound with a 70% yield. A slow evaporation dichloromethane solution of the product gave a colourless crystals suitable for X-ray diffraction.

Refinement
All H atoms attached to C and N atoms were fixed geometrically and treated as riding with C-H = 0.93 Å and N-H = 0.86 Å with U iso (H) = 1.2U eq (C or N). H atoms of water molecule were located in difference Fourier maps and included in the subsequent refinement using restraints (O-H= 0.85 (1)Å and H···H= 1.39 (2) Å) with U iso (H) = 1.5U eq (O). In the last cycles of refinement, they were treated as riding on their parent O atom.
Some residual electron density were difficult to model and therefore, the SQUEEZE function of PLATON (Spek, 2009) was used to eliminate the contribution of the electron density in the solvent region from the intensity data, and the solvent-free model was employed for the final refinement. There is one cavity of 122.9 Å 3 per unit cell. PLATON estimated that the cavity contains 38.4 electrons which may correspond to a solvent molecule of dichloromethane as suggested by chemical analyses.
This dichloromethane solvent has been however included in the formula.