Crystal structure and Hirshfeld surface analysis of 2,2,2-trifluoro-1-(7-methylimidazo[1,2-a]pyridin-3-yl)ethan-1-one

In the crystal, the molecules are linked by C—H⋯N and C—H⋯O hydrogen bonds into strips, which are connected by F⋯F contacts into layers.

To visualize the intermolecular interactions in the title compound, the 3D Hirshfeld surfaces and two-dimensional fingerprint plots were computed using Crystal Explorer 17 (Turner et al., 2017). The Hirshfeld surface plotted over d norm in the range À0.3137 to 1.1314 a.u. is shown in Fig. 6. The intense red spots with negative d norm values represent C-HÁ Á ÁO and C-HÁ Á ÁN hydrogen bonds. Pale red spots correspond tointeractions, which are also seen in the shapeindex surface (Fig. 7) generated in the range À1 to 1 Å , where they are indicated by adjacent red and blue triangles. The Molecular structure of the title compound showing the atom labelling and displacement ellipsoids drawn at the 50% probability level.

Figure 4
Packing diagram of the title compound, viewed down the b axis showing the C-HÁ Á ÁO and C-HÁ Á ÁN hydrogen bonds and the FÁ Á ÁF andstacking interactions. Hydrogen atoms not involved in hydrogen bonding are omitted.

Figure 5
Packing diagram of the title compound, viewed down the c axis showing the C-HÁ Á ÁO and C-HÁ Á ÁN hydrogen bonds and the FÁ Á ÁF andstacking interactions. Hydrogen atoms not involved in hydrogen bonding are omitted.

Figure 6
Hirshfeld surface of the title molecule mapped over d norm . (

Database survey
The most closely related compounds containing a similar imidazo[1,2-a]pyridine skeleton, but with different substituents on the amide N atom are: Fun et al., 2011). In the crystal of XOWVOX, molecules are linked by N-HÁ Á ÁH hydrogen bonds, forming chains along the c-axis direction. The chains are linked by C-HÁ Á Á interactions, forming slabs parallel to the ac plane. In the structure of KOXGEM, an intramolecular C-HÁ Á ÁN hydrogen bond forms an S(5) ring motif. In the crystal, a short HÁ Á ÁH contact links adjacent molecules into centrosymmetric dimers. The dimers are joined by weak C-HÁ Á Á and slippedstacking interactions, forming layers parallel to (110), which are connected into a three-dimensional network by short BrÁ Á ÁH contacts. In the crystal of PILGAV01, N-HÁ Á ÁN hydrogen bonds link the molecules into [010] chains. The cohesion of the crystal structure of DABTEI is ensured by C-HÁ Á ÁN and C-HÁ Á ÁO hydrogen bonds, forming layers parallel to the ac plane. In ZAPJAD, the supramolecular structure is defined by two kinds of intermolecular hydrogen bonds. Pairs of N-HÁ Á ÁN hydrogen bonds link the molecules into centrosymmetric dimers and N-HÁ Á ÁO hydrogen bonds link the dimers into tubular chains running along the a-axis direction. In the crystal of ULEGOI, molecules are linked into chains through pairs of C-HÁ Á ÁN interactions, forming R 2 2 (12) and R 2 2 (8) hydrogenbond ring motifs. These chains are stacked along the a axis.   (11) 2 À x, 1 À y, Àz H10CÁ Á ÁO1 2.83 1 À x, 2 À y, 1 À z F2Á Á ÁH10A 2.64 x, y, À1 + z H2Á Á ÁF2 2.80 1 À x, 1 À y, Àz C3Á Á ÁN1 3.3055 (16) 1 À x, 1 À y, 1 À z

Figure 8
View of the three-dimensional Hirshfeld surface of the title molecule plotted over electrostatic potential energy in the range À0.0500 to 0.0500 a.u. calculated at the Hartree-Fock level of theory using the STO-3 G basis set. Hydrogen-bond donors and acceptors are shown as blue and red regions around the atoms, corresponding to positive and negative potentials, respectively.

Refinement
Crystal data, data collection and structure refinement details are summarized in Table 3. Hydrogen atoms were positioned geometrically (C-H = 0.95-0.98 Å ) and refined as riding, with U iso (H) = 1.2U eq (C) for CH hydrogen atoms and U iso (H) = 1.5U eq (C) for CH 3 hydrogen atoms.   CrysAlis PRO (Rigaku OD, 2021); program(s) used to solve structure: SHELXT (Sheldrick, 2015a); program(s) used to refine structure: SHELXL (Sheldrick, 2015b); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: PLATON (Spek, 2020).  (14) Special details Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.