2-(2-Chlorophenoxy)acetohydrazide

In the title compound, C8H9ClN2O2, the acetohydrazide group is approximately planar, with the maximum deviation of 0.031 (2) Å. In the crystal, the molecules are linked by N—H⋯N, N—H⋯O and C—H⋯O hydrogen bonds, with the acetohydrazide O atom accepting two C—H⋯O links and one N—H⋯O link. This results in infinite sheets lying parallel to (100).

In the title compound, C 8 H 9 ClN 2 O 2 , the acetohydrazide group is approximately planar, with the maximum deviation of 0.031 (2) Å . In the crystal, the molecules are linked by N-HÁ Á ÁN, N-HÁ Á ÁO and C-HÁ Á ÁO hydrogen bonds, with the acetohydrazide O atom accepting two C-HÁ Á ÁO links and one N-HÁ Á ÁO link. This results in infinite sheets lying parallel to (100).

Experimental
O-chloro phenol (11 ml, 1.00 mmol), ethyl chloroacetate (10.7 ml, 1.00 mmol) and potassium carbonate (20.75 g, 1.50 mmol) were refluxed in acetone (100 ml) at 80 °c for 18 h. The reaction mixture is then filtered, distilled to remove the acetone and poured into ice cold water with vigorous stirring. The ester, phenoxy ethyl acetate was extracted using ether.
The solution was distilled to remove ether. Phenoxy ethyl acetate (8.2 ml, 0.50 mmol) was heated at 100 °C for 10h in an absolute alcohol medium (40 ml) with hydrazine hydrate (2.5 ml, 0.50 mmol). The reaction mixture was allowed to cool, the solid separated was filtered, dried and recrystallized from ethanol. The yield was found to be 7.1 g (71 %). M. p. 384-385 K (Holla & Udupa, 1992).

Refinement
Atoms H1N1, H1N2 and H2N2 were located from the difference Fourier map and refined freely. The remaining H atoms were positioned geometrically and refined using a riding model, with C-H = 0.93 and 0.97 Å and U iso (H) = 1.2 U eq (C). Fig. 1. The molecular structure of (I), showing 50% probability displacement ellipsoids.

Special details
Experimental. The crystal was placed in the cold stream of an Oxford Cyrosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K.
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 > 2sigma(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.