(1RS,2SR,5SR)-9-Benzyl-2-[(1RS)-1-hydroxybenzyl]-9-azabicyclo[3.3.1]nonan-3-one from synchrotron data

In the crystal structure of the racemic title compound, C22H25NO2, solved and refined against sychrotron diffraction data, the hydroxy group and the carbonyl O atom participate in the formation of O—H⋯O hydrogen bonds between pairs of enantiomers related by a crystallographic centre of symmetry.

In the crystal structure of the racemic title compound, C 22 H 25 NO 2 , solved and refined against sychrotron diffraction data, the hydroxy group and the carbonyl O atom participate in the formation of O-HÁ Á ÁO hydrogen bonds between pairs of enantiomers related by a crystallographic centre of symmetry.   Table 1 Hydrogen-bond geometry (Å , ).
The crystal structure of the title compound contains one molecule in the asymmetric unit ( Fig. 1). Two intermolecular hydrogen bonds are formed between a pair of enantiomers in the crystal lattice. hydroxy group and carbonyl oxygen atom of the azabicyclo[3.3.1]nonan-3-one system participate in this interaction (Table 1, Fig. 2).

Experimental
A solution of n-butyllithium in hexane (2.5M, 0.88 mL, 2.0 mmol) was added dropwise to a cooled (273 K) and stirred solution of diisopropylamine (0.3 ml, 2.2 mmol) in tetrahydrofuran (6 mL). The mixture was stirred for 30 min at 273 K, and cooled down to 195 K. Then a solution of N-benzylnorgranatanone (0.459 g, 2.0 mmol) in tetrahydrofuran (3 mL) was added dropwise. After stirring for 90 min, benzaldehyde (0.22 ml, 2.18 mmol) was added dropwise and the mixture was stirred for another 15 min. The reaction was quenched with saturated aq. NH 4 Cl (2 mL), the mixture was diluted with water (10 mL), and extracted with dichloromethane (3 × 20 mL). The combined organic extracts were dried over Na 2 SO 4 and concentrated to give the crude product as a white solid (0.663 g, 99%). Crystallization from a mixed solvent system heptane/dichloromethane gave the product (0.243 g, 75%) as white crystals.

Refinement
All hydrogen atoms were constrained to idealized positions with C-H distances fixed at 0.95-1.00 Å and O-H distances fixed at 0.84 Å and U iso (H) = 1.5U eq (C) for hydroxy hydrogen atom and 1.2U eq (C) for others.

Figure 1
The molecular structure of the title compound. Displacement ellipsoids are drawn at the 50% probability level.   where P = (F o 2 + 2F c 2 )/3 (Δ/σ) max = 0.001 Δρ max = 0.58 e Å −3 Δρ min = −0.30 e Å −3 Special details Experimental. The crystal was mounted with vaseline on a pin-attached capillary. Upon mounting, the crystal was quenched to 100 K in a nitrogen-gas stream supplied by an Oxford Cryo-Jet. Diffraction data were measured at the station 24-ID-C of the APS synchrotron by rotation method. Geometry. All e.s.d.'s are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. 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 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.  (7) C22-C23 1.3941 (9) C10-O10 1.4232 (7) C22-H22 0.9500 C10-C11 1.5133 (7) C23-H23 0.9500 C10-H10 1.0000