2-(6-Hydroxy-1-benzofuran-3-yl)acetamide

In the title compound, C10H9NO3, the dihedral angle between the benzofuran ring system (r.m.s. deviation for the non-H atoms = 0.009 Å) and the –C—C(O)—N– segment is 83.76 (1)°. In the crystal, molecules are linked by N—H⋯O and O—H⋯O hydrogen bonds, generating (001) sheets, which feature C(4) and C(10) chains.


Related literature
For a related structure and background to benzofurans, see: Arunakumar et al. (2014).

Comment
As part of our ongoing structural studies of functionalsied benzofuran ring systems at the C-2 position (Arunakumar et al., 2014), we now describe the structure of the title compound, (I).

Experimental
(6-Hydroxy-1-benzofuran-3-yl)acetic acid (0.015 mmol) was taken in a round bottom flask containing N,N-dimethyl formamide (15 ml)·To this 1, 1-carbonydiimadazole (0.023 mmol) was added at 273 K. The reaction mixture was stirred for 45 minutes. Ammonium acetate (0.046 mmol) and triethyl amine (1 ml) were added, the reaction mixture was stirred at room temperature overnight. The completion of the reaction was monitored by thin layer chromatography. After completion of the reaction, the reaction mixture was diluted with ethylacetate and the organic layer was washed with water followed by brine solution. The organic layer was dried over anhydrous sodium sulfate and concentrated to give the crude product. It was further purified by column chromatography by using Ethyl acetate and petroleum ether (8:2) as eluent.
Colourless prisms were obtained from the solvent system: ethyl acetate / methanol (4:1) at room temperature.

Refinement
The H atoms were positioned with idealized geometry using a riding model with C-H = 0.93-0.97 Å and O-H = 0.82 Å. The H atoms of the NH 2 group were located in a difference map and later refined freely. The isotropic displacement parameters for all H atoms were set to 1.2 times U eq (Carbon) and 1.5 times U eq (Oxygen)..

Computing details
Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT-Plus (Bruker, 2009); data reduction: SAINT-Plus and XPREP (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).      Zig-zag pattern observed in the crystal structure.  where P = (F o 2 + 2F c 2 )/3 (Δ/σ) max < 0.001 Δρ max = 0.15 e Å −3 Δρ min = −0.28 e Å −3 Absolute structure: Flack (1983), 1927 Friedel pairs Absolute structure parameter: −0.2 (2) Special details Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'s 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 > 2σ(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.