Crystal structure of 2,2-diphenylhydrazinium chloride

In the title molecule, the phenyl rings are inclined to one another by 78.63 (17)°. In the crystal, molecules are linked via N—H⋯Cl hydrogen bonds, forming chains along [10-1], which enclose two adjacent (6) ring motifs.


Chemical context
1,1 0 -Diphenylhydrazine is a 'free' hydrazine, viz with an NH 2 group. It has been used as a starting reagent for the preparation of Schiff bases as fluorescent sensors for fluoride (Mukherjee et al., 2014), and metal complexes (Stender et al., 2003;Clulow et al., 2008). The title compound, (I), crystallized out of a reaction of 1,1 0 -diphenylhydrazine with 2,6-diacetylpyridine in an attempt to prepare the ligand 2,6-diacetylpyridine bis(N,N-diphenylhydrazone). The latter compound is one of a series that has been used to prepare bis(imino)pyridyl iron and cobalt complexes to study the effect of nitrogen substituents on ethylene oligomerization and polymerization (Britovsek et al., 2001).

Structural commentary
The molecular structure of the title salt, (I), is illustrated in Fig. 1, and selected bond distances and bond angles are given ISSN 1600-5368

Figure 1
A view of the molecular structure of the title compound with atom labelling. Displacement ellipsoids are drawn at the 50% probability level.
The structure of salt (II) is very similar to that of the title compound, (I). The two phenyl rings are inclined to one another by 80.04 (19) compared to 78.63 (17) in (I). The bond lengths and angles involving the central N atom are also very similar to those in (I). The central N atom is displaced by 0.358 (3) Å from the plane of the three attached N and C atoms, and the sum of their bond angles is 342.0 , indicating clearly the pyramidal nature of the central N atom, as in (I).

Figure 2
A partial view normal to (101) of the crystal packing of the title compound. Hydrogen bonds are shown as dashed lines (see Table 2 for details; C-bound H atoms have been omitted for clarity).

Figure 3
A view along the b axis of the crystal packing of the title compound. Hydrogen bonds are shown as dashed lines (see Table 2 for details; Cbound H atoms not involved in hydrogen bonding have been omitted for clarity).

Synthesis and crystallization
Brown block-like crystals of the title compound were obtained during an attempt to prepare the ligand 2,6-diacetylpyridine bis(N,N-diphenylhydrazone) by a condensation reaction involving 1,1 0 -diphenylhydrazinium hydrochloride and 2,6-diacetylpyridine in methanol.

Refinement details
Crystal data, data collection and structure refinement details are summarized in Table 3. The ammonium H atoms were located in a difference Fourier map and freely refined. The Cbound H atoms were included in calculated positions and treated as riding atoms: C-H = 0.95 Å with U iso (H) = 1.2U eq (C).    (Spek, 2009) and Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXL2013 (Sheldrick, 2008), PLATON (Spek, 2009) and publCIF (Westrip, 2010).

Special details
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.