7-Methoxy-3,4-dihydronaphthalen-1(2H)-one

In the title compound, C11H12O2, the six-membered ketone ring fused to the 7-methoxy benzene ring adopts a slightly distorted envelope configuration with the central methylene C atom being the flap. The crystal packing is stabilized by weak intermolecular C—H⋯O and C—H⋯π interactions, which lead to supramolecular layers in the bc plane.

In the title compound, C 11 H 12 O 2 , the six-membered ketone ring fused to the 7-methoxy benzene ring adopts a slightly distorted envelope configuration with the central methylene C atom being the flap. The crystal packing is stabilized by weak intermolecular C-HÁ Á ÁO and C-HÁ Á Á interactions, which lead to supramolecular layers in the bc plane.
SS thanks the UOM for the research facilities. JPJ acknowledges the NSF-MRI program (grant No. CHE1039027) for funds to purchase the X-ray diffractometer.

intermolecular interactions.
Experimental Anisole (4.3 ml, 0.040 mol) is acylated with succinic anhydride (4.2 g, 0.042 mol) in the presence of anhydrous aluminium chloride and nitrobenzene as solvent to give the intermediate keto acid. The keto group is reduced by hydrogenation with Pd/C as catalyst at 2-3 kgs pressure and 343-348 K for 2 -3 hours. Further work up, isolation and cyclization with poly phosphoric acid (PPA) gives 7-methoxy-1-tetralone (Fig. 1). X-ray quality crystals of (I) were obtained by slow evaporation from isopropyl alcohol (M.pt.: 333-336 K).

Refinement
All of the H atoms were placed in their calculated positions and then refined using the riding model with Atom-H lengths of 0.95 Å (CH), 0.99 Å (CH 2 ) or 0.98 Å (CH 3 ). Isotropic displacement parameters for these atoms were set to 1.19-1.20 (CH, CH 2 ) or 1.49 (CH 3 ) times U eq of the parent atom. Fig. 1 supplementary materials sup-3

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 > σ(F 2 ) is used only for calculating Rfactors(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.