(Z)-1-[(2E)-3,4-Diphenyl-2,3-dihydro-1,3-thiazol-2-ylidene]-2-[1-(4-hydroxyphenyl)ethylidene]hydrazinium bromide including an unknown solvate

In the title compound, C23H20N3OS+·Br−, the dihydrothiazole ring (r.m.s. deviation = 0.015 Å) is twisted with respect to each of the C- and N-bound phenyl rings and the hydroxybenzene ring, making dihedral angles of 76.0 (2), 71.2 (2) and 9.8 (2)°, respectively. In the crystal, inversion-related molecules are linked by association of the bromide ions with the cations via N—H⋯Br and O—H⋯Br hydrogen-bonding interactions. These molecules run in channels parallel to the a axis through face-to-face π–π stacking interactions between the hydroxybenzene rings [centroid–centroid distances = 3.785 (3) Å] which, in turn, are connected into layers parallel to (110) by weak C—H⋯π interactions. A small region of electron density well removed from the main molecule and appearing disordered over a center of symmetry was removed with PLATON SQUEEZE [Spek (2009 ▶). Acta Cryst. D65, 148–15] following unsuccessful attempts to model it as plausible solvent molecule. The nature of the solvent was not known and hence, this is not taken into account when calculating M r and related data.

In the title compound, C 23 H 20 N 3 OS + ÁBr À , the dihydrothiazole ring (r.m.s. deviation = 0.015 Å ) is twisted with respect to each of the C-and N-bound phenyl rings and the hydroxybenzene ring, making dihedral angles of 76.0 (2), 71.2 (2) and 9.8 (2) , respectively. In the crystal, inversion-related molecules are linked by association of the bromide ions with the cations via N-HÁ Á ÁBr and O-HÁ Á ÁBr hydrogen-bonding interactions. These molecules run in channels parallel to the a axis through face-to-facestacking interactions between the hydroxybenzene rings [centroid-centroid distances = 3.785 (3) Å ] which, in turn, are connected into layers parallel to (110) by weak C-HÁ Á Á interactions. A small region of electron density well removed from the main molecule and appearing disordered over a center of symmetry was removed with PLATON SQUEEZE [Spek (2009). Acta Cryst. D65,  following unsuccessful attempts to model it as plausible solvent molecule. The nature of the solvent was not known and hence, this is not taken into account when calculating M r and related data.
The support of Tulane University for the Tulane Crystallography Laboratory is gratefully acknowledged.
In the crystal, inversion-related molecules are linked by association of the bromide ions with the cations via N-H···Br and O-H···Br hydrogen bonding interactions (Table 1, Fig. 2). These molecules run in channels parallel to the a axis through the face-to-face π-π stacking interactions [centroid-to-centroid distances = 3.785 (3) Å] between the hydroxylbenzene rings: these are connected into layers parallel to (110) by weak C5-H5···Cg(C18-C23) interactions, Table 1.

Synthesis and crystallization
The title compound was prepared according to our reported method (Mague et al., 2014). The crude product has been crystallized from ethanol to afford colorless crystals suitable for X-ray diffraction (m.p.: 533 -535 K).

Refinement
All H atoms were fixed geometrically and treated as riding with C-H= 0.94-0.97 Å, N-H = 0.91 Å and O-H = 0.83 Å, and with U iso (H)= 1.2U eq (C,N) and 1.5 U eq (O). A small region of electron density well-removed from the main molecule and appearing disordered over a center of symmetry was removed with PLATON SQUEEZE following unsuccessful attempts to model it as plausible lattice solvent (Spek, 2009  Perspective view of the asymmetric unit with 30% probability displacement ellipsoids.

Figure 2
Packing viewed down the a axis and showing O-H···Br interactions. where P = (F o 2 + 2F c 2 )/3 (Δ/σ) max < 0.001 Δρ max = 1.09 e Å −3 Δρ min = −0.48 e Å −3 Special details Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles 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. H-atoms attached to carbon were placed in calculated positions (C-H = 0.95 -0.98 Å) while those attached to nitrogen were placed in locations derived from a difference map and their coordinates adjusted to give N-H = 0.91 Å. That attached to oxygen was placed in an idealized position and the C-C-O-H torsion angle refined (AFIX 147)·All were included as riding contributions with isotropic displacement parameters 1.2 -1.5 times those of the attached atoms. A small region of electron density well removed from the main molecule and appearing disordered over a center of symmetry was removed with PLATON SQUEEZE following unsuccessful attempts to model it as plausible lattice solvent (Spek, 2014).