Morpholine–4-nitrophenol (1/2)

In the title adduct, 2C6H5NO3·C4H9NO, the morpholine ring adopts a chair conformation. The dihedral angle between the two nitrophenol rings is 69.47 (9)°. The nitro groups attached to the benzene rings make dihedral angles of 3.37 (16) and 3.14 (13)° in the two molecules of nitrophenol. The crystal structure is stabilized by N—H⋯O, O—H⋯N and O—H⋯O hydrogen bonds and further consolidated by C—H⋯O interactions, resulting in a three-dimensional network.

In the title adduct, 2C 6 H 5 NO 3 ÁC 4 H 9 NO, the morpholine ring adopts a chair conformation. The dihedral angle between the two nitrophenol rings is 69.47 (9) . The nitro groups attached to the benzene rings make dihedral angles of 3.37 (16) and 3.14 (13) in the two molecules of nitrophenol. The crystal structure is stabilized by N-HÁ Á ÁO, O-HÁ Á ÁN and O-HÁ Á ÁO hydrogen bonds and further consolidated by C-HÁ Á ÁO interactions, resulting in a three-dimensional network.

Comment
4-(4-Nitrophenyl)morpholine derivatives are of great importance due to their anticancer activity (Wang et al., 2010). The title adduct is a key intermediate in the synthetic investigations of antitumor drugs. We report the preparation and crystal structure of the title adduct in this paper.
In the title adduct ( Fig. 1), the morpholine ring adopts a chair conformation. The dihedral angle between the two nitrophenol rings is 69.47 (9)°. The nitro group attached with the benzene ring (C1-C6) makes a dihedral angle of 3.37 (16)°, while the other nitro group attached with the other benzene ring (C7-C12) makes a dihedral angle of 3.14 (13)°. The

Experimental
Morpholine and 4-Nitrophenol were taken in equimolar (1:1) ratio using ethanol as solvent. The solution was filtered in a clean beaker and optimally closed. The solution was kept at room temperature. After two weeks, a product was obtained which was subsequently recrystallised from ethanol resulting in yellow coloured crystals suitable for X-ray diffraction.

Refinement
All C-bound H atoms were positioned geometrically and refined using a riding model, with C-H = 0.93 and 0.97 Å, for aryl and methylene H-atoms, respectively. The hydroxyl H-atoms were included at geometrically calculated positions with O-H = 0.82 Å. The H-atom bonded to N3 was located from a difference map and allowed to refine freely. The U iso (H) were allowed at 1.5U eq (O) or 1.2U eq (C/N).

Computing details
Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 2012); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009    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 > 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.