Table 3. Experimental details.

	(R*,S*)-3	(R*,R*)-4
Crystal data
Chemical formula	C22H29NO2	C22H29NO2
M r	339.46	339.46
Crystal system, space group	Monoclinic, P21/n	Orthorhombic, P c a21
Temperature (K)	223	223
a, b, c (Å)	10.3594 (2), 18.8246 (4), 10.9981 (3)	9.2049 (5), 25.4468 (17), 8.2451 (6)
α, β, γ (°)	90, 117.889 (1), 90	90, 90, 90
V (Å3)	1895.65 (8)	1931.3 (2)
Z	4	4
Radiation type	Cu Kα	Cu Kα
μ (mm−1)	0.59	0.58
Crystal size (mm)	0.40 × 0.25 × 0.10	0.35 × 0.05 × 0.03
Data collection
Diffractometer	Nonius KappaCCD APEXII	Nonius KappaCCD APEXII
Absorption correction	Multi-scan (DENZO; Otwinowski et al., 2003 ▸)	Multi-scan (DENZO; Otwinowski et al., 2003 ▸)
T min, T max	0.799, 0.944	0.824, 0.983
No. of measured, independent and observed [I > 2σ(I)] reflections	8812, 3077, 2864	8312, 2885, 2164
R int	0.034	0.082
(sin θ/λ)max (Å−1)	0.600	0.599
Refinement
R[F 2 > 2σ(F 2)], wR(F 2), S	0.045, 0.118, 1.04	0.087, 0.231, 1.25
No. of reflections	3077	2885
No. of parameters	229	229
No. of restraints	0	1
H-atom treatment	H-atom parameters constrained	H-atom parameters constrained
Δρmax, Δρmin (e Å−3)	0.16, −0.13	0.26, −0.25

Computer programs: COLLECT (Nonius, 1998 ▸), DENZO–SMN (Otwinowski & Minor, 1997 ▸), SHELXS97, SHELXL97 and XP in SHELXTL (Sheldrick, 2008 ▸), Mercury (Macrae et al., 2008 ▸) and PLATON (Spek, 2009 ▸).