[meso-5,10,15,20-Tetrakis(5-bromothiophen-2-yl)porphyrinato-κ4 N,N′,N′′,N′′′]nickel(II)

The NiII atom in the title porphyrin complex, [Ni(C36H16Br4N4S4)], is in a square-planar geometry defined by four pyrrole N atoms. There is considerable buckling in the porphyrin ring with the dihedral angles between the N4 donor set and the pyrrole rings being in the range 17.0 (3)–18.8 (3)°. Each of the six-membered chelate rings is twisted about an Ni—N bond and the dihedral angles between diagonally opposite chelate rings are 13.08 (15) and 13.45 (11)°; each pair of rings is orientated in opposite directions. The bromothienyl rings are twisted out of the plane of the central N4 core with dihedral angles in the range 51.7 (2)–74.65 (19)°. Supramolecular chains along [001] are formed through C—H⋯Br interactions in the crystal packing. Three of the four bromothienyl units are disordered over two coplanar positions of opposite orientation with the major components being in 0.691 (3), 0.738 (3) and 0.929 (9) fractions.

The Ni II atom in the title porphyrin complex, [Ni(C 36 H 16 Br 4 N 4 S 4 )], is in a square-planar geometry defined by four pyrrole N atoms. There is considerable buckling in the porphyrin ring with the dihedral angles between the N 4 donor set and the pyrrole rings being in the range 17.0 (3)-18.8 (3) . Each of the six-membered chelate rings is twisted about an Ni-N bond and the dihedral angles between diagonally opposite chelate rings are 13.08 (15) and 13.45 (11) ; each pair of rings is orientated in opposite directions. The bromothienyl rings are twisted out of the plane of the central N 4 core with dihedral angles in the range 51.7 (2)-74. 65 (19) . Supramolecular chains along [001] are formed through C-HÁ Á ÁBr interactions in the crystal packing. Three of the four bromothienyl units are disordered over two coplanar positions of opposite orientation with the major components being in 0.691 (3), 0.738 (3) and 0.929 (9) fractions.
The Ni II atom in (I), Fig. 1, is in a square-planar geometry defined by four pyrrole-N atoms, Table 1. The coordination geometry resembles that observed in the analogous Zn II complex (Ghazzali et al., 2008). However, in contrast to the literature structure in which the porphyrin molecule (excluding the bromothienyl residues) is essentially planar, there is considerable buckling in (I). This is quantified by the dihedral angles between the N 4 donor set and the N1-N4-pyrrole rings of 18.8 (3), 18.0 (3), 17.0 (3) and 17.8 (2)°, respectively. This is further quantified in the parameters associated with the six-membered chelate rings. There is a measure of buckling in each of these about an Ni-N bond: NiN1N2 ring (N3) and -0.120 (1) Å (Ni)]. The dihedral angles between diagonally opposite six-membered rings are 13.08 (15)° (NiN1N2/NiN3N4) and 13.45 (11)° (NiN2N2/NiN1N4) but each pair is orientated in opposite directions. Each of the bromothienyl rings is twisted out of the plane of the central N 4 core with the dihedral angles between this and the S1-S4 thienyl rings (major components of the disorder only) being 59.2 (3), 51.7 (2), 71.5 (2) and 74.65 (19)°, respectively.
In the crystal packing, supramolecular chains along [001] are formed through C-H···Br interactions involving the bromide atom of the only non-disordered bromothienyl ring, Fig. 2 and Table 1.

Refinement
Carbon-bound H-atoms were placed in calculated positions [C-H = 0.95 Å, U iso (H) = 1.2U eq (C)] and were included in the refinement in the riding model approximation.
Three of the four bromothienyl units are disordered over two positions, the major components being in 0.691 (3), 0.738 (3) and 0.929 (9) fractions. Pairs of 1,2-related distances were restrained to within 0.01 Å and pairs of the1,3-related ones to within 0.02 Å of each other. The U ij parameters of the primed carbon atoms were set to those of the unprimed ones; the U ij parameters of the bromine and sulfur atoms were not tied but the U ij parameters were restrained to be nearly isotropic.
For the major components, the atoms were restrained to lie on a plane. Pairs of C porphyrin -C thiophene distances were also restrained to within 0.01 Å of each other.

Figure 1
The molecular structure of the title compound showing the atom-labelling scheme and displacement ellipsoids at the 70% probability level. Only the major components of the disorder are shown.