(Anilino{(Z)-2-[(E)-5-bromo-3-methoxy-2-oxidobenzylidene]hydrazin-1-ylidene-κ2 O 2,N 2}methanethiolato-κS)(4,4′-dimethyl-2,2′-bipyridine-κ2 N,N′)zinc N,N-dimethylformamide monosolvate

The asymmetric unit of the title compound, [Zn(C15H12BrN3O2S)(C12H12N2)]·C3H7NO, contains two independent molecules with a similar structure. The doubly deprotonated Schiff base ligand O,N,S-chelates to the metal atom, and the three coordinating atoms along with one N atom of the substituted 2,2′-bipyridine ligand constitute the square plane of the distorted square pyramid surrounding the metal atom. The apical site is occupied by the second N atom of the substituted 2,2′-bipyridine. The secondary amine group of the Schiff base dianion forms a hydrogen bond to the O atom of the dimethylformamide solvent. In the crystal, the phenyl ring of one of the two Schiff base anions is disordered over two positions in a 1:1 ratio. The crystal studied is a racemic twin.

The asymmetric unit of the title compound, [Zn(C 15 H 12 Br-N 3 O 2 S)(C 12 H 12 N 2 )]ÁC 3 H 7 NO, contains two independent molecules with a similar structure. The doubly deprotonated Schiff base ligand O,N,S-chelates to the metal atom, and the three coordinating atoms along with one N atom of the substituted 2,2 0 -bipyridine ligand constitute the square plane of the distorted square pyramid surrounding the metal atom. The apical site is occupied by the second N atom of the substituted 2,2 0 -bipyridine. The secondary amine group of the Schiff base dianion forms a hydrogen bond to the O atom of the dimethylformamide solvent. In the crystal, the phenyl ring of one of the two Schiff base anions is disordered over two positions in a 1:1 ratio. The crystal studied is a racemic twin.

Experimental
Crystal data [Zn(C 15 H 12   The doubly-deprotonated Schiff base in O,N,S-chelates to the metal atom, and the three coordinating atoms along with the N atom of the substituted bipyridine ligand comprise the square plane of the square pyramid surrounding it. The apical site is occupied by the second N atom of the substituted 2,2′-bipyridine. In one molecule, the Zn is displaced by 0.305 (3) Å in the direction of the apical occupant ( Fig. 1) whereas in the other, the displacement is 0.103 (6) Å in the opposite direction (Fig. 2). The secondary amino group of the Schiff-base dianion forms a hydrogen bond to the O atom of the DMF (Table 1).

Refinement
Carbon-and nitrogen bound H-atoms were placed in calculated positions (C-H 0.93 to 0.96 Å, N-H 0.88 Å) and were included in the refinement in the riding model approximation, with U(H) set to 1.2 to 1.5U(C,N).
All aromatic and pyridine rings were refined as rigid hexagons of 1.39 Å sides. One of the phenyl rings of the Schiffbase anion is disordered over two positions in a 1:1 ratio. The temperature factors of the primed atoms were set to those of the unprimed ones but in the reverse order (i.e., those of C11 to those of C15), and the pair of N-C phenyl distances were restrained to within 0.01 Å of each other.
The molecules of DMF were each restrained to lie on a plane; their. The anisotropic temperature factors were restrained to be nearly isotropic. The final difference Fourier map had a peak at 0.91 Å from Br1 and a hole at 0.96 Å from Br2.
The base scale factor was explicitly refined.