Crystal structure of N,N′-didecylpyromellitic diimide

The title compound comprises a central pyromellitic diimide moiety with terminal decyl groups, with potential applications as an acaricide, insecticide and mematicide.


Chemical context
Previous studies have proposed that pyromellitic diimide derivatives have potential applications in energy storage materials (Song et al., 2010) and photovoltaic devices (Kanosue & Ando, 2016). Additionally, aromatic diimides can act as organic semiconductors (Shao et al., 2014). Recently, our group reported a copper(I) coordination polymer with a pyromellitic diimide ligand, namely N,N 0 -bis[2-(cyclohexylthio)ethyl]pyromellitic diimide, and showed that the ligand has two conformations, syn and anti. In addition, a reversible anti to syn transition was achieved by agitating in mixed organic solvents (Kang et al., 2015). In an extension of our studies of pyromellitic diimide derivatives, we have prepared the title compound by the reaction of pyromellitic dianhydride with decylamine and report its crystal structure herein.

Structural commentary
The title compound consists of a central pyromellitic diimide with two terminal decyl groups (Fig. 1). The centre of the ISSN 2056-9890 molecule lies on a crystallographic inversion centre and the asymmetric unit of the title compound is composed of one half-molecule. The decyl chains are inclined at an angle of 67.96 to the plane of the pyromellitic diimide ring. The decyl chains point in opposite directions, forming a rod-shaped conformation with a distance of 32.45 Å between the carbon atoms of the terminal decyl groups.

Figure 2
Intermolecular C-HÁ Á ÁO hydrogen bonds (yellow dashed lines) [symmetry code: (i) x, Ày + 3 2 , z À 1 2 ] in the crystal of (I). H atoms and terminal decyl chains not involved in intermolecular interactions have been omitted for clarity.

Figure 1
The asymmetric unit of the title compound, with displacement ellipsoids drawn at the 50% probability level. H atoms are shown as small spheres of arbitrary radius. Unlabelled atoms are generated by the symmetry operation (1 À x, 1 À y, 2 À z).

Theoretical calculations
DFT calculations have been performed to support the experimental values on the basis of the diffraction study using the GAUSSIAN09 software package (Frisch et al., 2009). Full geometry optimizations were performed using B3LYP levels of theory with a 6-311G* basis set. The optimized parameters such as bond lengths and bond angles are in excellent agreement with the experimental crystallographic data (Table 2). In particular, the theoretical value (67.07 ) for the angle between the decyl chain and the plane of the pyromellitic diimide ring is almost equal that obtained from the experimental crystallographic data (67.96 ).

Figure 4
The program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: DIAMOND (Brandenburg, 2010); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and publCIF (Westrip, 2010). 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.