**3.1 Structural analysis of 4,5-dimethyl-1,2-diphenyl-1***H***-imidazole monohydrate (DMDPIMH)**

This section shows the structure details of DMDPIMH [10]. SIR2004 [18] solved the structure by using direct methods. SHELXL97 [19] refined the final crystal structure model.

This compound belongs to the tetragonal crystal system with the space group I41/a. Molecular formula: C17H16N2.H2O; molecular weight: 266.33; crystal data: a = b = 25.5498 Å; c = 9.3792 (1) Å; α = β = γ = 90°; V = 6122.67 (9) Å<sup>3</sup> ; Z = 16; Dx = 1.156 Mg m<sup>3</sup> ; F(000) = 2272; final R[F<sup>2</sup> > 2σ(F2 )] = 0.043 and wR(F<sup>2</sup> ) = 0.134 for 2610 reflections observed with I > 2σ(I).

In multiple Fourier maps, the water atoms H1W and H2W coupled to the oxygen atom O1W were found and freely refined. With CdH = 0.93–0.96 Å; Uiso(H) = kUeq(C), where k = 1.5 for dCH3 and 1.2 for the other H atoms, the other hydrogen atoms were positioned geometrically and supported by their parent atoms. The dCH3 groupings are disorganized over two locations. Each was enhanced as an idealized disordered dCH3 group.

In this compound (**Figure 2**), with a maximum deviation of 0.0037 (7) Å for C5, the imidazole ring is planar. The imidazole ring makes dihedral angles of 80.74 (7) and 41.62 (7) ° with the ring (C11dC16) and the ring (C21dC26), respectively. 75.83 (8) ° is the dihedral angle among the phenyl rings. Intermolecular hydrogen bonds O1WdH1W⋯N3 (y + 1/4, x + 1/4, z + 1/4) and O1W—H2W⋯O1W (y + 1/4, x + 1/4, z + 1/4) are found in the crystal structure (**Figure 3**).

*Selected Imidazole Derivatives: Synthesis and X-Ray Crystal Structure – A Review DOI: http://dx.doi.org/10.5772/intechopen.108488*

The ORTEP-3 for Windows drew the thermal displacement ellipsoid plot with a 30% probability level [20] (**Figure 2**). The crystal packing using the PLATON [21] was viewed along the c-axis (**Figure 3**).
