Bis(benzo[h]quinolin-10-olato-κ2 N,O)bromidomanganese(III)

The manganese(III) atom of the title compound is coordinated by one bromide and two benzo[h]quinolin-10-olate ligands and exhibits a distorted square-pyramidal coordination environment.


Structure description
Recently, we described the chemoselective reduction of quinolines and related N-heterocycles by molecular hydrogen, using a simple Mn I complex [Mn(CO) 5 Br] (Papa et al., 2020). During the mechanistic studies of this catalytic reaction, several manganese compounds starting from [Mn(CO) 5 Br] and different N-heteroarenes were prepared and characterized by spectroscopic methods. In this context, the title compound was synthesized and structurally determined by single-crystal X-ray diffraction. The molecular structure consists of a manganese(III) atom coordinated by one bromido and two bidentate benzo[h]quinolin-10-olato ligands (Fig. 1). The coordination environment around the Mn III atom is best described as distorted square-pyramidal with the Br ligand in the apical position ( = 0.35, with = 0 for an ideal square pyramid and = 1 for an ideal trigonal bypramid; Addison et al., 1984). The deviation from planarity in the strained benzo[h]quinolin-10-olato ligands can be derived from the torsion angles N1-C13-C12-C11 of 10.0 (3) and N2-C26-C25-C24 of 11.0 (3) .
The crystal structure of a dimeric indium complex containing two benzo[h]quinolin-10-olato units has been reported by Wu et al. (1999). In addition, the crystal structure of 10-hydroxybenzo[h]quinoline has been described by Kubicki et al. (1995).

Figure 1
Molecular structure of the title compound with atom labelling and displacement ellipsoids drawn at the 50% probability level.

Figure 2
Packing diagram of the title compound along the a axis. Displacement ellipsoids are drawn at the 50% probability level. For clarity H atoms have been omitted. The alternating pattern ofstacking interactions between N1/C1-C4/C13 rings as well as between C7-C12 rings is shown with dotted lines.

data-1
IUCrData (  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.