N-Hydroxy-N-o-tolylacetamide

In the molecule of the title compound, C9H11NO2, the methyl C atom bonded to the ring and the N atom lie in the benzene ring plane. An intramolecular O—H⋯O hydrogen bond results in the formation of a five-membered planar ring, which is oriented at a dihedral angle of 81.37 (3)° with respect to the benzene ring. In the crystal structure, intermolecular O—H⋯O hydrogen bonds link the molecules stacked along the b axis. There are also π–π interactions between benzene rings with a face-to-face stacking distance of 3.434 Å.

In the molecule of the title compound, C 9 H 11 NO 2 , the methyl C atom bonded to the ring and the N atom lie in the benzene ring plane. An intramolecular O-HÁ Á ÁO hydrogen bond results in the formation of a five-membered planar ring, which is oriented at a dihedral angle of 81.37 (3) with respect to the benzene ring. In the crystal structure, intermolecular O-HÁ Á ÁO hydrogen bonds link the molecules stacked along the b axis. There are alsointeractions between benzene rings with a face-to-face stacking distance of 3.434 Å .

Comment
The title compound, (I), contains hydroxy and formyl groups, which can react with different groups to prepare various function organic compounds. It is a kind of aromatic organic intermediate that can be used for many fields such as pesticide, paper making etc. (Fu et al., 2000). We report herein its crystal structure.
In the molecule of (I), (Fig. 1), the bond lengths (Allen et al., 1987) and angles are within normal ranges. The atoms N and C1 lie in the benzene ring plane. The intramolecular O-H···O hydrogen bond (Table 1) results in the formation of a five-membered planar ring A (O1/H1A/O2/N/C8). The dihedral angle between five-and six-membered rings is 81.37 (3)°.
In the crystal structure, intermolecular O-H···O hydrogen bonds (Table 1) link the molecules stacked along the b axis ( Fig. 2), in which they may be effective in the stabilization of the structure.
There are also the π-π interactions of benzene rings with a face-to-face stacking distance of 3.434 Å.

Experimental
The title compound, (I), was prepared by the literature method (Fu et al., 2000). Crystals suitable for X-ray analysis were obtained by dissolving (I) (0.5 g) in petroleum ether (20 ml) and evaporating the solvent slowly at room temperature for about 7 d.

Refinement
H atoms were positioned geometrically, with O-H = 0.82 Å (for OH) and C-H = 0.93 and 0.96 Å for aromatic and methyl H, respectively, and constrained to ride on their parent atoms, with U iso (H) = xU eq (C,O), where x = 1.2 for aromatic H, and x = 1.5 for all other H atoms. Fig. 1. The molecular structure of the title molecule, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level. 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.