4-Hydroxyindan-1-one

The molecule of the title compound, C9H8O2, is essentially planar except for the methylene H atoms [maximum deviation = 0.028 (1) Å]. In the crystal, the molecules are linked by classical O—H⋯O hydrogen bonds and weak C—H⋯O interactions into chains along [110] and [1-10].

The molecule of the title compound, C 9 H 8 O 2 , is essentially planar except for the methylene H atoms [maximum deviation = 0.028 (1) Å ]. In the crystal, the molecules are linked by classical O-HÁ Á ÁO hydrogen bonds and weak C-HÁ Á ÁO interactions into chains along [110] and [110].

Experimental
The molecular structure of the title compound is shown in Figure 1. The molecule is essentially planar (the maximum deviation = 0.028 (1) Å), which is consistent with previous studies (Ali et al., 2010;Chen et al., 2011a,b). In the crystal ( Fig. 2), molecules are linked by intermolecular O-H···O and C-H···O hydrogen bonds (Table 1) to form an infinite one-dimensional chain along and [1 1 0 and ][1 -1 0], generating two different kinds of C(7) motifs (Bernstein et al., 1995).

Experimental
The title compound was synthesized by the hydrolation of 4-benzoyloxy-1-indanone with sodium hydroxide (Gerasov et al., 2011). Colorless parallelepiped -shaped crystals suitable for the crystallographic studies reported here were isolated over a period of five weeks by slow evaporation from a ethyl acetate solution.

Refinement
H atoms bonded to O and C atoms were located in a difference electron density map. The hydroxy H atom and the C sp3 H atoms were freely refined, and the C sp2 H atoms repositioned geometrically and refined using a riding model, [C-H = 0.93 Å and U iso (H) = 1.2U eq (C)].

Computing details
Data collection: SMART (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX publication routines (Farrugia, 1999).  The molecular structure of the title compound, showing 50% probability displacement ellipsoids. 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.