Crystal structure of (5-{3-[(1,4,7,10,13-pentaoxa-16-azacyclooctadecan-16-yl)carbonylamino]phenyl}-10,15,20-triphenylporphyrinato)cobalt(II)

In the title compound, the central CoII atom is coordinated by four pyrrole N atoms of the porphyrin core and one O atom of the crown ether. Intramolecular N—H⋯O and intermolecular C—H⋯π interactions are observed

The cobalt(II) cation is displaced slightly from the porphyrin core to the axial ligand, as illustrated by the displacement of the metal atom from the 24-atom mean plane (Á 24 = 0.06 Å ). The title compound shows a distorted porphyrin core conformation. The mean absolute core-atom displacements C a , C b , C m and C av are 0.14 (10), 0.20 (10), 0.24 (4) and 0.18 (10) Å , respectively. Diagrams of the porphyrin core of the title compound. Averaged values of the chemically unique bond lengths (in Å ) and angles (in ) are shown. The numbers in parentheses are the s.u. values calculated on the assumption that the averaged values are all drawn from the same population. The perpendicular displacements (in units of 0.01 Å ) of the porphyrin core atoms from the 24-atom mean plane are also displayed. Positive values of the displacements are towards the oxygen atom as the axial ligand. Table 1 Hydrogen-bond geometry (Å , ).

Figure 3
The C-HÁ Á Á interactions in the title compound. Dashed lines show the distances between hydrogen atoms of the crown ether and the porphyrin core plane. Other atoms have been omitted for clarity.

Figure 1
The molecular structure of the title compound, with displacement ellipsoids drawn at the 50% probability level.
An intramolecular N-HÁ Á ÁO interaction is found between one of the oxygen atoms (O2) of the crown ether and the nitrogen atom (N5) of the amide linker. The distance between O2 and N5 is 2.886 (2) ( Table 1), consistent with the range (2.70-3.05 Å ) suggested for the existence of N-HÁ Á ÁO hydrogen bonding (Bertolasi et al., 1995).

Supramolecular features
In the title compound, as seen in Fig. 3, the distances between the hydrogen atoms (H30A, H31A, H32A, H33A) of the crown ether and the plane of the neighbouring porphyrin core are 2.52, 2.57, 2.71 and 2.34 Å , all of which are smaller than 2.9 Å , a limit suggested for the existence of C-HÁ Á Á interactions (Takahashi et al., 2001). The molecular packing is shown in Fig. 4.

Figure 4
A view of the molecular packing of the title compound in the crystal structure. H atoms have been omitted for clarity.

Refinement
Crystal data, data collection and structure refinement details are summarized in Table 2. The hydrogen atoms attached to the nitrogen atom (N5) of the amide linker and the carbon atoms (C30, C31, C32, C33) of the crown ether were placed in the locations derived from a difference map, while others were placed in calculated positions (C-H = 0.95, 0.99 Å for aryl and methine H atoms, respectively). Hydrogen atoms were refined using a riding model with fixed isotropic displacement parameters of U iso (H) = 1.2U eq (C). One outlier was omitted in the last cycles of refinement. Data collection: APEX2 (Bruker, 2013); cell refinement: APEX2 and SAINT (Bruker, 2013); data reduction: SAINT and XPREP (Bruker, 2013); program(s) used to solve structure: SHELXT (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015b); molecular graphics: XP (Sheldrick, 2008); software used to prepare material for publication: SHELXCIF2014 (Sheldrick, 2015b) and enCIFer (Allen et al., 2004).
(  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. 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 > 2sigma(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.