5-Bromo-2-hydroxybenzaldehyde 4-ethylthiosemicarbazone

In the title Schiff base compound, C10H12BrN3OS, the C—N—N—C torsion angle is 172.07 (11)°. An intramolecular hydrogen bond exists between the hydroxy H atom and the azomethine N atom. In the crystal, pairs of hydrogen bonds involving the imino H atom and the S atom give rise to supramolecular dimers.

In the title Schiff base compound, C 10 H 12 BrN 3 OS, the C-N-N-C torsion angle is 172.07 (11) . An intramolecular hydrogen bond exists between the hydroxy H atom and the azomethine N atom. In the crystal, pairs of hydrogen bonds involving the imino H atom and the S atom give rise to supramolecular dimers.
In the title compound, a strong intramolecular hydrogen bond O-H···N is observed. An intermolecular N-H···S hydrogen bond connects two molecules into a supramolecular dimer as shown in Figure 2.

Refinement
Carbon-bound H-atoms were placed in calculated positions (C-H 0.95, 0.98 and 0.99 Å) and were included in the refinement in the riding model approximation, with U iso (H) =1.5U eq (C) for methyl H atoms and 1.2U eq (C) for the others.
The hydroxy and amino H atoms were located in a difference Fourier map, and were refined with distance restraints of O -H 0.85±0.01 and N-H 0.88±0.01 Å; with U iso (H) =1.2U eq (N and O).  Displacement ellipsoid plot (50% probability level) of the title compound, with atom numbering of structurally unique non-H atoms and the H atoms.

Figure 2
The packing diagram of the title compound, with H atoms omitted for clarity. Hydrogen bonds are shown as dashed lines. 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 > σ(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.