2-(4-Bromophenoxy)propanohydrazide

The title compound, C9H11BrN2O2, is an important intermediate for the synthesis of heterocyclic compounds such as azoles, 2,5-disubstituted-1,3,4-oxadiazoles and 5-substituted 2-mercapto-1,3,4-oxadiazoles. The bromophenoxy group subtends a dihedral angle of 82.81 (7)° with the plane passing through the propanohydrazide moiety. The crystal structure is stabilized by intermolecular N—H⋯O hydrogen bonds that form columns extending along the b axis.

MKR is grateful to the HEC-Pakistan for financial support for a PhD program under scholarship No. ILC-0363104.

Experimental
Methyl 2-(4-bromophenoxy)propionate (5.0 g, 0.0193 mol) was dissolved in methanol (20 ml) and hydrazine hydrate (80%, 3.50 mL, 0.0679 mol) added slowly with stirring. The reaction mixture was set to reflux. After completion of the reaction (TLC, 6 hrs), the reaction mixture was concentrated and poured to water. The precipitated solid was filtered and recrystallized from ethanol/ water. The spectroscopic and physical characterization data will be reported separately.

Refinement
The H atoms on the N atoms were refined isotropically. Other H atoms were placed in idealized positions and treated as riding atoms with C-H distance in the range 0.95-1.000 Å and U iso (H) = 1.2U eq (C) or 1.5U eq (C). Fig. 1. The molecular structure of (I) showing the atom labelling and displacement ellipsoids drawn at the 50% probability level.

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 > σ(F 2 ) is used only for calculating Rfactors(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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å 2 )
x y z U iso */U eq C1 0.4780 (