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Acta Cryst. (2011). E67, o1483    [ doi:10.1107/S1600536811018101 ]

2-{(1R,2R)-2-[Bis(4-methylbenzyl)amino]cyclohexyl}isoindoline-1,3-dione

C. Li, X.-K. Fu, C.-L. Wu and J. Huang

Abstract top

In the title molecule, C30H32N2O2, the two tolyl rings form dihedral angles of 65.8 (1) and 6.6 (1)° with the isoindole-1,3-dione mean plane. The cyclohexane ring adopts a chair conformation.

Comment top

Chiral tertiary amines are efficient catalysts for direct aldol reactions of ketones with aldehydes (Paradowska et al., 2009). Therefore, it is of great interest for us to investigate the novel chiral tertiary amine as a chiral catalyst. In this article we would like to report the crystal structure of the title compound (I).

In (I) (Fig. 1), two tolyl rings form dihedral angles of 65.8 (1) and 6.6 (1)°, respectively, with the isoindole-1,3-dione mean plane. Cyclohexane ring adopts a chair conformation. This type of molecular geometry was reported also by Gawronski et al. (1998). It could be found that in the crystal structures the cyclohexane rings adopt chair conformations with phthalimide rings in equatorial orientation.

Related literature top

For applications of chiral tertiary amines as catalysts for direct aldol reactions, see: Paradowska et al. (2009). For details of the synthesis, see: Kaik & Gawroński (2003); Gawronski et al. (1998).

Experimental top

To a solution of (1R,2R)-N-phthaloyl-1,2-diaminocyclohexane (2.44 g, 10 mmol) (Kaik et al., 2003; Gawronski et al., 1998) in acetonitrile (50 ml) was added at room temperature K2CO3 (3.20 g, 23 mmol) and 4-methylbenzyl chloride (3 mL, 25 mmol). The mixture was refluxed with stirring for 5 h. The solvent was removed in vacuo and the mixture was extracted with dichloromethane and NaHCO3 solution. The organic solution was dried over MgSO4 and evaporated. Product was directly purified through flash column chromatography on a slilca gel to afford white solid. A crystal of (I) suitable for X-ray analysis was grown from diethyl ether by slow evaporation at room temperature.

Refinement top

All H atoms were placed in idealized positions and treated as riding, with C—H = 0.96 (CH3), Uiso(H) = 1.5 Ueq(CH3), and C—H = 0.97 (CH2), 0.98 or 0.93 Å (CH), Uiso(H) = 1.2 Ueq(CH and CH2). In the absence of any significant anomalous scatterers in the molecule, attempts to confirm the absolute structure by refinement of the Flack parameter in the presence of 1479 sets of Friedel equivalents led to an inconclusive value of -1.1 (17). Therefore, the Friedel pairs were merged before the final refinement and the absolute configuration was assigned to correspond with that of the known chiral centres in a precursor molecule, which remained unchanged during the synthesis of the title compound.

Computing details top

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT (Bruker, 2000); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I) showing the atomic numbering and 20% probability displacement ellipsoids.
2-{(1R,2R)-2-[Bis(4-methylbenzyl)amino]cyclohexyl}isoindoline- 1,3-dione top
Crystal data top
C30H32N2O2F(000) = 484
Mr = 452.58Dx = 1.148 Mg m−3
Monoclinic, P21Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ybCell parameters from 1969 reflections
a = 12.472 (2) Åθ = 2.8–21.3°
b = 9.2853 (17) ŵ = 0.07 mm−1
c = 12.505 (2) ÅT = 298 K
β = 115.305 (2)°Block, colourless
V = 1309.1 (4) Å30.38 × 0.24 × 0.24 mm
Z = 2
Data collection top
Bruker SMART APEX
diffractometer		2042 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.022
graphiteθmax = 25.5°, θmin = 1.8°
φ and ω scansh = −13→15
6901 measured reflectionsk = −9→11
2597 independent reflectionsl = −14→15
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.047Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.112H-atom parameters constrained
S = 1.11 w = 1/[σ2(Fo2) + (0.0526P)2 + 0.0478P]
where P = (Fo2 + 2Fc2)/3
2597 reflections(Δ/σ)max = 0.001
309 parametersΔρmax = 0.10 e Å−3
1 restraintΔρmin = −0.11 e Å−3
Crystal data top
C30H32N2O2V = 1309.1 (4) Å3
Mr = 452.58Z = 2
Monoclinic, P21Mo Kα radiation
a = 12.472 (2) ŵ = 0.07 mm−1
b = 9.2853 (17) ÅT = 298 K
c = 12.505 (2) Å0.38 × 0.24 × 0.24 mm
β = 115.305 (2)°
Data collection top
Bruker SMART APEX
diffractometer		2042 reflections with I > 2σ(I)
6901 measured reflectionsRint = 0.022
2597 independent reflectionsθmax = 25.5°
Refinement top
R[F2 > 2σ(F2)] = 0.047H-atom parameters constrained
wR(F2) = 0.112Δρmax = 0.10 e Å−3
S = 1.11Δρmin = −0.11 e Å−3
2597 reflectionsAbsolute structure: ?
309 parametersFlack parameter: ?
1 restraintRogers parameter: ?
Special details top

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) 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. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
C10.3760 (3)0.0454 (4)0.7604 (3)0.0615 (8)
H10.38110.03570.84050.074*
C20.4270 (3)−0.0921 (4)0.7338 (3)0.0780 (10)
H2A0.4295−0.08250.65770.094*
H2B0.5076−0.10510.79340.094*
C30.3546 (3)−0.2234 (4)0.7319 (4)0.0917 (12)
H3A0.3862−0.30690.70840.110*
H3B0.3606−0.24080.81080.110*
C40.2260 (3)−0.2031 (4)0.6470 (4)0.1012 (13)
H4A0.1805−0.28630.65030.121*
H4B0.2190−0.19490.56690.121*
C50.1767 (3)−0.0685 (4)0.6784 (4)0.0910 (12)
H5A0.1791−0.08020.75650.109*
H5B0.0944−0.05680.62250.109*
C60.2455 (3)0.0666 (4)0.6772 (3)0.0658 (8)
H60.24100.07440.59720.079*
C70.4942 (2)0.2658 (4)0.8556 (2)0.0581 (7)
C80.4647 (3)0.2219 (4)0.6645 (3)0.0641 (8)
C90.5322 (3)0.3581 (4)0.7045 (2)0.0646 (8)
C100.5750 (3)0.4513 (5)0.6459 (3)0.0876 (11)
H100.56410.43320.56870.105*
C110.6349 (3)0.5730 (5)0.7066 (4)0.0955 (12)
H110.66420.63860.66950.115*
C120.6514 (3)0.5976 (5)0.8200 (4)0.0961 (12)
H120.69310.67900.85920.115*
C130.6079 (3)0.5051 (4)0.8780 (3)0.0806 (10)
H130.61800.52370.95480.097*
C140.5493 (2)0.3844 (4)0.8184 (2)0.0588 (8)
C150.1637 (3)0.1925 (5)0.7988 (3)0.0837 (10)
H15A0.22460.14070.86380.100*
H15B0.09030.13880.77380.100*
C160.1474 (3)0.3400 (5)0.8414 (3)0.0747 (9)
C170.0420 (4)0.3825 (5)0.8398 (4)0.0908 (12)
H17−0.02310.32110.80860.109*
C180.0302 (4)0.5158 (5)0.8841 (4)0.0945 (13)
H18−0.04240.54070.88330.113*
C190.1212 (4)0.6106 (5)0.9284 (3)0.0828 (11)
C200.2259 (4)0.5699 (6)0.9282 (4)0.1076 (14)
H200.28990.63310.95680.129*
C210.2390 (4)0.4372 (7)0.8866 (4)0.1091 (15)
H210.31230.41240.88900.131*
C220.1084 (4)0.7562 (6)0.9758 (4)0.1147 (15)
H22A0.04000.75560.99250.172*
H22B0.09900.82900.91800.172*
H22C0.17790.77631.04710.172*
C230.0991 (3)0.2557 (5)0.5925 (3)0.0788 (10)
H23A0.05670.32910.61410.095*
H23B0.04430.17770.55430.095*
C240.1419 (3)0.3184 (4)0.5070 (3)0.0675 (9)
C250.1056 (3)0.2635 (5)0.3942 (3)0.0793 (10)
H250.05650.18300.37070.095*
C260.1426 (3)0.3289 (6)0.3161 (3)0.0906 (13)
H260.11690.29140.24020.109*
C270.2150 (4)0.4459 (5)0.3467 (3)0.0855 (11)
C280.2522 (4)0.4976 (5)0.4595 (4)0.0971 (12)
H280.30270.57670.48330.117*
C290.2161 (4)0.4344 (4)0.5382 (3)0.0859 (11)
H290.24290.47160.61430.103*
C300.2538 (5)0.5162 (8)0.2598 (4)0.140 (2)
H30A0.20790.47820.18200.209*
H30B0.33630.49670.28280.209*
H30C0.24170.61840.25930.209*
N10.4460 (2)0.1719 (3)0.76050 (19)0.0566 (6)
N20.1976 (2)0.2011 (3)0.6999 (2)0.0671 (7)
O10.49097 (18)0.2479 (3)0.95003 (16)0.0775 (7)
O20.4310 (2)0.1639 (3)0.56978 (19)0.0869 (7)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0628 (17)0.062 (2)0.0575 (16)−0.0014 (16)0.0233 (14)0.0042 (15)
C20.0661 (19)0.065 (2)0.092 (2)0.0084 (18)0.0231 (18)0.0055 (19)
C30.085 (2)0.061 (2)0.116 (3)0.005 (2)0.031 (2)0.003 (2)
C40.084 (2)0.066 (3)0.132 (3)−0.006 (2)0.026 (2)−0.014 (2)
C50.062 (2)0.076 (3)0.122 (3)−0.008 (2)0.026 (2)−0.006 (2)
C60.0595 (17)0.065 (2)0.0681 (18)0.0039 (17)0.0226 (15)−0.0002 (17)
C70.0476 (15)0.072 (2)0.0478 (15)0.0018 (15)0.0139 (12)0.0009 (15)
C80.0733 (19)0.070 (2)0.0529 (17)0.0020 (17)0.0310 (15)−0.0014 (17)
C90.0653 (18)0.071 (2)0.0595 (18)−0.0003 (17)0.0288 (15)0.0083 (17)
C100.104 (3)0.091 (3)0.078 (2)−0.009 (3)0.049 (2)0.007 (2)
C110.104 (3)0.087 (3)0.101 (3)−0.024 (3)0.048 (2)0.011 (3)
C120.091 (3)0.081 (3)0.098 (3)−0.020 (2)0.023 (2)0.000 (2)
C130.081 (2)0.086 (3)0.067 (2)−0.015 (2)0.0242 (18)−0.008 (2)
C140.0514 (16)0.065 (2)0.0538 (16)−0.0007 (15)0.0161 (13)−0.0004 (15)
C150.093 (2)0.080 (3)0.093 (2)0.007 (2)0.053 (2)0.010 (2)
C160.081 (2)0.084 (3)0.0734 (19)0.006 (2)0.0466 (18)0.009 (2)
C170.095 (3)0.080 (3)0.120 (3)−0.003 (2)0.067 (2)0.010 (3)
C180.097 (3)0.093 (3)0.118 (3)0.016 (3)0.071 (3)0.014 (3)
C190.098 (3)0.094 (3)0.063 (2)0.005 (2)0.039 (2)0.004 (2)
C200.092 (3)0.125 (4)0.104 (3)−0.015 (3)0.041 (2)−0.038 (3)
C210.079 (2)0.140 (4)0.115 (3)0.003 (3)0.048 (2)−0.037 (3)
C220.150 (4)0.103 (4)0.087 (3)0.015 (3)0.048 (3)−0.009 (3)
C230.0663 (19)0.084 (3)0.079 (2)0.016 (2)0.0249 (17)0.001 (2)
C240.0640 (18)0.064 (2)0.0644 (19)0.0193 (17)0.0176 (15)0.0024 (17)
C250.0636 (19)0.085 (3)0.078 (2)0.0056 (19)0.0194 (17)−0.015 (2)
C260.080 (2)0.119 (4)0.062 (2)0.018 (3)0.0195 (19)−0.012 (2)
C270.090 (3)0.089 (3)0.074 (2)0.022 (3)0.031 (2)0.016 (2)
C280.119 (3)0.066 (2)0.091 (3)−0.001 (2)0.031 (2)0.009 (2)
C290.120 (3)0.063 (2)0.064 (2)0.003 (2)0.029 (2)0.0004 (19)
C300.149 (4)0.164 (6)0.126 (4)0.026 (4)0.078 (3)0.040 (4)
N10.0595 (13)0.0603 (16)0.0502 (12)−0.0025 (13)0.0236 (11)0.0015 (12)
N20.0656 (15)0.0680 (19)0.0686 (15)0.0087 (14)0.0296 (13)0.0038 (14)
O10.0797 (13)0.1028 (19)0.0471 (11)−0.0103 (14)0.0243 (10)0.0023 (12)
O20.1193 (18)0.0876 (17)0.0625 (13)−0.0082 (16)0.0472 (13)−0.0137 (13)
Geometric parameters (Å, °) top
C1—N11.463 (4)C15—C161.514 (6)
C1—C61.524 (4)C15—H15A0.9700
C1—C21.525 (4)C15—H15B0.9700
C1—H10.9800C16—C171.365 (5)
C2—C31.511 (5)C16—C211.374 (6)
C2—H2A0.9700C17—C181.390 (6)
C2—H2B0.9700C17—H170.9300
C3—C41.510 (5)C18—C191.354 (6)
C3—H3A0.9700C18—H180.9300
C3—H3B0.9700C19—C201.360 (6)
C4—C51.517 (6)C19—C221.512 (6)
C4—H4A0.9700C20—C211.374 (7)
C4—H4B0.9700C20—H200.9300
C5—C61.524 (5)C21—H210.9300
C5—H5A0.9700C22—H22A0.9600
C5—H5B0.9700C22—H22B0.9600
C6—N21.464 (4)C22—H22C0.9600
C6—H60.9800C23—N21.470 (4)
C7—O11.211 (3)C23—C241.501 (5)
C7—N11.387 (4)C23—H23A0.9700
C7—C141.474 (4)C23—H23B0.9700
C8—O21.201 (4)C24—C291.364 (5)
C8—N11.398 (4)C24—C251.382 (4)
C8—C91.483 (5)C25—C261.385 (5)
C9—C141.369 (4)C25—H250.9300
C9—C101.380 (5)C26—C271.359 (6)
C10—C111.388 (6)C26—H260.9300
C10—H100.9300C27—C281.369 (5)
C11—C121.361 (6)C27—C301.513 (6)
C11—H110.9300C28—C291.376 (5)
C12—C131.376 (5)C28—H280.9300
C12—H120.9300C29—H290.9300
C13—C141.371 (5)C30—H30A0.9600
C13—H130.9300C30—H30B0.9600
C15—N21.470 (4)C30—H30C0.9600
N1—C1—C6111.1 (3)N2—C15—H15B109.2
N1—C1—C2111.6 (2)C16—C15—H15B109.2
C6—C1—C2112.5 (3)H15A—C15—H15B107.9
N1—C1—H1107.1C17—C16—C21116.2 (4)
C6—C1—H1107.1C17—C16—C15122.0 (4)
C2—C1—H1107.1C21—C16—C15121.8 (3)
C3—C2—C1112.1 (3)C16—C17—C18121.2 (4)
C3—C2—H2A109.2C16—C17—H17119.4
C1—C2—H2A109.2C18—C17—H17119.4
C3—C2—H2B109.2C19—C18—C17121.9 (4)
C1—C2—H2B109.2C19—C18—H18119.0
H2A—C2—H2B107.9C17—C18—H18119.0
C4—C3—C2111.0 (3)C18—C19—C20117.2 (4)
C4—C3—H3A109.4C18—C19—C22122.0 (4)
C2—C3—H3A109.4C20—C19—C22120.8 (4)
C4—C3—H3B109.4C19—C20—C21121.3 (4)
C2—C3—H3B109.4C19—C20—H20119.3
H3A—C3—H3B108.0C21—C20—H20119.3
C3—C4—C5110.3 (3)C20—C21—C16122.2 (4)
C3—C4—H4A109.6C20—C21—H21118.9
C5—C4—H4A109.6C16—C21—H21118.9
C3—C4—H4B109.6C19—C22—H22A109.5
C5—C4—H4B109.6C19—C22—H22B109.5
H4A—C4—H4B108.1H22A—C22—H22B109.5
C4—C5—C6112.5 (3)C19—C22—H22C109.5
C4—C5—H5A109.1H22A—C22—H22C109.5
C6—C5—H5A109.1H22B—C22—H22C109.5
C4—C5—H5B109.1N2—C23—C24111.9 (2)
C6—C5—H5B109.1N2—C23—H23A109.2
H5A—C5—H5B107.8C24—C23—H23A109.2
N2—C6—C5114.9 (2)N2—C23—H23B109.2
N2—C6—C1112.5 (3)C24—C23—H23B109.2
C5—C6—C1109.2 (3)H23A—C23—H23B107.9
N2—C6—H6106.6C29—C24—C25118.0 (3)
C5—C6—H6106.6C29—C24—C23120.4 (3)
C1—C6—H6106.6C25—C24—C23121.5 (3)
O1—C7—N1124.5 (3)C24—C25—C26119.7 (4)
O1—C7—C14128.7 (3)C24—C25—H25120.2
N1—C7—C14106.8 (2)C26—C25—H25120.2
O2—C8—N1125.6 (3)C27—C26—C25122.2 (3)
O2—C8—C9128.6 (3)C27—C26—H26118.9
N1—C8—C9105.8 (2)C25—C26—H26118.9
C14—C9—C10121.1 (3)C26—C27—C28117.5 (4)
C14—C9—C8108.5 (3)C26—C27—C30121.4 (4)
C10—C9—C8130.4 (3)C28—C27—C30121.1 (5)
C9—C10—C11117.3 (3)C27—C28—C29121.1 (4)
C9—C10—H10121.3C27—C28—H28119.4
C11—C10—H10121.3C29—C28—H28119.4
C12—C11—C10120.8 (4)C24—C29—C28121.4 (4)
C12—C11—H11119.6C24—C29—H29119.3
C10—C11—H11119.6C28—C29—H29119.3
C11—C12—C13121.7 (4)C27—C30—H30A109.5
C11—C12—H12119.1C27—C30—H30B109.5
C13—C12—H12119.1H30A—C30—H30B109.5
C14—C13—C12117.5 (3)C27—C30—H30C109.5
C14—C13—H13121.2H30A—C30—H30C109.5
C12—C13—H13121.2H30B—C30—H30C109.5
C9—C14—C13121.4 (3)C7—N1—C8110.9 (3)
C9—C14—C7108.0 (3)C7—N1—C1123.1 (2)
C13—C14—C7130.7 (3)C8—N1—C1125.8 (3)
N2—C15—C16112.1 (3)C6—N2—C23111.6 (3)
N2—C15—H15A109.2C6—N2—C15113.9 (3)
C16—C15—H15A109.2C23—N2—C15111.1 (2)
N1—C1—C2—C3−179.3 (3)C18—C19—C20—C21−1.0 (7)
C6—C1—C2—C3−53.7 (4)C22—C19—C20—C21179.3 (4)
C1—C2—C3—C454.5 (5)C19—C20—C21—C161.1 (8)
C2—C3—C4—C5−56.2 (5)C17—C16—C21—C200.1 (7)
C3—C4—C5—C658.2 (5)C15—C16—C21—C20−178.3 (4)
C4—C5—C6—N2176.5 (3)N2—C23—C24—C29−61.9 (4)
C4—C5—C6—C1−56.0 (4)N2—C23—C24—C25119.8 (3)
N1—C1—C6—N2−52.1 (3)C29—C24—C25—C26−1.6 (5)
C2—C1—C6—N2−178.0 (3)C23—C24—C25—C26176.9 (3)
N1—C1—C6—C5179.1 (3)C24—C25—C26—C270.6 (5)
C2—C1—C6—C553.2 (4)C25—C26—C27—C280.6 (6)
O2—C8—C9—C14178.8 (3)C25—C26—C27—C30−179.6 (4)
N1—C8—C9—C14−0.7 (3)C26—C27—C28—C29−0.8 (6)
O2—C8—C9—C10−1.2 (6)C30—C27—C28—C29179.4 (4)
N1—C8—C9—C10179.3 (3)C25—C24—C29—C281.4 (5)
C14—C9—C10—C11−0.6 (5)C23—C24—C29—C28−177.1 (3)
C8—C9—C10—C11179.4 (3)C27—C28—C29—C24−0.2 (6)
C9—C10—C11—C120.7 (6)O1—C7—N1—C8−179.6 (3)
C10—C11—C12—C13−1.2 (7)C14—C7—N1—C8−0.6 (3)
C11—C12—C13—C141.5 (6)O1—C7—N1—C15.5 (4)
C10—C9—C14—C131.0 (5)C14—C7—N1—C1−175.5 (2)
C8—C9—C14—C13−179.0 (3)O2—C8—N1—C7−178.7 (3)
C10—C9—C14—C7−179.6 (3)C9—C8—N1—C70.8 (3)
C8—C9—C14—C70.4 (3)O2—C8—N1—C1−4.0 (5)
C12—C13—C14—C9−1.4 (5)C9—C8—N1—C1175.5 (3)
C12—C13—C14—C7179.4 (3)C6—C1—N1—C7108.9 (3)
O1—C7—C14—C9179.1 (3)C2—C1—N1—C7−124.7 (3)
N1—C7—C14—C90.1 (3)C6—C1—N1—C8−65.2 (4)
O1—C7—C14—C13−1.6 (5)C2—C1—N1—C861.2 (4)
N1—C7—C14—C13179.5 (3)C5—C6—N2—C23−82.1 (4)
N2—C15—C16—C17120.1 (3)C1—C6—N2—C23152.1 (3)
N2—C15—C16—C21−61.6 (5)C5—C6—N2—C1544.6 (4)
C21—C16—C17—C18−1.3 (6)C1—C6—N2—C15−81.2 (3)
C15—C16—C17—C18177.1 (3)C24—C23—N2—C6−73.6 (4)
C16—C17—C18—C191.3 (6)C24—C23—N2—C15158.1 (3)
C17—C18—C19—C20−0.1 (6)C16—C15—N2—C6164.1 (3)
C17—C18—C19—C22179.5 (4)C16—C15—N2—C23−68.9 (4)
Acknowledgements top

The authors are grateful to the Southwest University of China for financial support.

references
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