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Acta Crystallographica Section E: Structure Reports Online logoLink to Acta Crystallographica Section E: Structure Reports Online
. 2011 Apr 22;67(Pt 5):o1181. doi: 10.1107/S1600536811014061

2,6-Bis[(S)-4-benzyl-4,5-dihydro-1,3-oxazol-2-yl]pyridine

Konstanze Möller a, Kathrin Junge a,*, Anke Spannenberg a, Matthias Beller a
PMCID: PMC3089107  PMID: 21754484

Abstract

The commercially available title compound, C25H23N3O2, has been known since 1993 [Nesper et al. (1993 ▶). Helv. Chim. Acta, 76, 2239–2249], but has not been structurally characterized until now. In the free ligand, the N atoms of both oxazoline rings point in opposite directions. The phenyl rings make dihedral angles of 30.56 (5) and 84.57 (3)° with the pyridine ring and 72.85 (3)° with each other.

Related literature

For the synthesis, see: Nesper et al. (1993 ▶; 1996 ▶); Schaus & Jacobsen (2000 ▶); Towers et al. (2003 ▶); Meng et al. (2005 ▶); Hui et al. (2006 ▶). For crystal structures showing the same ligand coordinated to Pd(BF4)2 or AgBF4, see: Nesper et al. (1996 ▶); Provent et al. (1997 ▶). For applications in asymmetric catalysis, see: Desimoni et al. (2003 ▶); Tse et al. (2006 ▶). graphic file with name e-67-o1181-scheme1.jpg

Experimental

Crystal data

  • C25H23N3O2

  • M r = 397.46

  • Orthorhombic, Inline graphic

  • a = 7.0184 (2) Å

  • b = 13.2654 (3) Å

  • c = 21.5542 (8) Å

  • V = 2006.74 (10) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 150 K

  • 0.50 × 0.45 × 0.25 mm

Data collection

  • Stoe IPDS II diffractometer

  • 38412 measured reflections

  • 5433 independent reflections

  • 4254 reflections with I > 2σ(I)

  • R int = 0.045

Refinement

  • R[F 2 > 2σ(F 2)] = 0.029

  • wR(F 2) = 0.053

  • S = 0.86

  • 5433 reflections

  • 271 parameters

  • H-atom parameters constrained

  • Δρmax = 0.13 e Å−3

  • Δρmin = −0.18 e Å−3

Data collection: X-AREA (Stoe & Cie, 2005 ▶); cell refinement: X-AREA; data reduction: X-AREA; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: XP in SHELXTL (Sheldrick, 2008 ▶); software used to prepare material for publication: SHELXL97.

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811014061/om2419sup1.cif

e-67-o1181-sup1.cif (19.3KB, cif)

Structure factors: contains datablocks I. DOI: 10.1107/S1600536811014061/om2419Isup2.hkl

e-67-o1181-Isup2.hkl (266.1KB, hkl)

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

supplementary crystallographic information

Comment

The synthesis of chiral tridentate N,N,N-pyridine-2,6-bisoxazolines (pybox ligands) constitute a useful toolbox for the application in asymmetric catalysis (Desimoni et al., 2003). The title compound was used as part of our ongoing studies (Tse et al., 2006).

In contrast to the complexed ligand (Nesper et al., 1996; Provent et al., 1997) where all N atoms are pointed to the metal to permit coordination, in the free ligand the N atoms of both oxazoline rings point in the opposite direction (Fig. 1). The dihedral angle between the planes defined by C13 - C18 and C20 - C25 is 72.85 (3)°. The phenyl rings (C13 - C18 and C20 - C25) are twisted out of the N1, C4 - C8 plane by an angle of 30.56 (5)° and 84.57 (3)°, respectively. The absolute configuration has been assigned to correspond with that of the known chiral centres of the starting material.

Experimental

The synthesis of the commercially available title compound was described by Nesper et al., 1993; Nesper et al., 1996; Schaus & Jacobsen, 2000; Towers et al., 2003; Meng et al., 2005 and Hui et al., 2006. The title compound was purchased from STREM and crystals were grown from a dichloromethane/hexane mixture. The solution was slowly evaporated to dryness for two days and colourless crystals suitable for X-ray analysis were isolated.

Refinement

H atoms were placed in idealized positions with d(C—H) = 0.99 (CH2) and 0.95–1.00 Å (CH) and refined using a riding model with Uiso(H) fixed at 1.2 Ueq(C).

Figures

Fig. 1.

Fig. 1.

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The molecular structure of the title compound showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 50% probability level.

Crystal data

C25H23N3O2 F(000) = 840
Mr = 397.46 Dx = 1.316 Mg m−3
Orthorhombic, P212121 Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab Cell parameters from 7372 reflections
a = 7.0184 (2) Å θ = 1.8–29.6°
b = 13.2654 (3) Å µ = 0.09 mm−1
c = 21.5542 (8) Å T = 150 K
V = 2006.74 (10) Å3 Prism, colourless
Z = 4 0.50 × 0.45 × 0.25 mm
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Data collection

Stoe IPDS II diffractometer 4254 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube Rint = 0.045
graphite θmax = 29.2°, θmin = 1.8°
ω scans h = −9→9
38412 measured reflections k = −18→18
5433 independent reflections l = −29→29
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Refinement

Refinement on F2 Primary atom site location: structure-invariant direct methods
Least-squares matrix: full Secondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.029 Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.053 H-atom parameters constrained
S = 0.86 w = 1/[σ2(Fo2) + (0.0277P)2] where P = (Fo2 + 2Fc2)/3
5433 reflections (Δ/σ)max = 0.001
271 parameters Δρmax = 0.13 e Å−3
0 restraints Δρmin = −0.18 e Å−3
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Special details

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.
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Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2)

x y z Uiso*/Ueq
C1 0.08221 (18) 0.78242 (8) 0.86378 (6) 0.0391 (3)
H1A 0.0477 0.8470 0.8436 0.047*
H1B 0.1124 0.7953 0.9079 0.047*
C2 −0.07905 (16) 0.70557 (7) 0.85760 (5) 0.0307 (2)
H2 −0.1664 0.7274 0.8235 0.037*
C3 0.18890 (16) 0.63775 (7) 0.82495 (5) 0.0271 (2)
C4 0.33449 (15) 0.56927 (7) 0.79877 (5) 0.0271 (2)
C5 0.30631 (16) 0.46567 (7) 0.80236 (5) 0.0320 (2)
H5 0.1993 0.4390 0.8238 0.038*
C6 0.43561 (16) 0.40269 (8) 0.77450 (5) 0.0330 (3)
H6 0.4199 0.3316 0.7762 0.040*
C7 0.58872 (16) 0.44469 (7) 0.74402 (5) 0.0302 (2)
H7 0.6801 0.4029 0.7241 0.036*
C8 0.60768 (16) 0.54896 (7) 0.74277 (5) 0.0261 (2)
C9 0.76549 (16) 0.59535 (7) 0.70744 (4) 0.0274 (2)
C10 1.02808 (19) 0.58556 (8) 0.64867 (6) 0.0410 (3)
H10A 1.0471 0.5688 0.6044 0.049*
H10B 1.1483 0.5731 0.6715 0.049*
C11 0.96205 (16) 0.69563 (8) 0.65652 (5) 0.0307 (2)
H11 0.9089 0.7199 0.6161 0.037*
C12 1.11831 (16) 0.76752 (8) 0.67706 (5) 0.0308 (2)
H12A 1.0595 0.8305 0.6927 0.037*
H12B 1.1903 0.7366 0.7116 0.037*
C13 1.25418 (16) 0.79284 (7) 0.62524 (5) 0.0287 (2)
C14 1.23770 (17) 0.88259 (8) 0.59240 (5) 0.0341 (2)
H14 1.1407 0.9293 0.6032 0.041*
C15 1.36016 (18) 0.90471 (10) 0.54433 (6) 0.0422 (3)
H15 1.3472 0.9665 0.5225 0.051*
C16 1.50168 (19) 0.83760 (9) 0.52768 (6) 0.0415 (3)
H16 1.5855 0.8528 0.4944 0.050*
C17 1.52003 (17) 0.74822 (9) 0.55991 (6) 0.0403 (3)
H17 1.6169 0.7016 0.5488 0.048*
C18 1.39795 (17) 0.72647 (8) 0.60832 (5) 0.0352 (3)
H18 1.4126 0.6650 0.6304 0.042*
C19 −0.19380 (17) 0.69334 (8) 0.91699 (5) 0.0338 (2)
H19A −0.3029 0.6477 0.9093 0.041*
H19B −0.1127 0.6623 0.9494 0.041*
C20 −0.26647 (15) 0.79374 (7) 0.93971 (5) 0.0284 (2)
C21 −0.19421 (16) 0.83776 (8) 0.99302 (5) 0.0331 (3)
H21 −0.0999 0.8031 1.0164 0.040*
C22 −0.25669 (18) 0.93129 (8) 1.01295 (5) 0.0369 (3)
H22 −0.2051 0.9603 1.0496 0.044*
C23 −0.39392 (18) 0.98226 (8) 0.97955 (6) 0.0385 (3)
H23 −0.4370 1.0466 0.9930 0.046*
C24 −0.46803 (17) 0.93922 (9) 0.92658 (6) 0.0380 (3)
H24 −0.5632 0.9739 0.9037 0.046*
C25 −0.40519 (17) 0.84613 (8) 0.90655 (5) 0.0329 (2)
H25 −0.4570 0.8175 0.8698 0.040*
N1 0.48293 (13) 0.61177 (6) 0.76977 (4) 0.02706 (19)
N2 0.02005 (14) 0.61231 (6) 0.83845 (4) 0.0311 (2)
N3 0.80484 (13) 0.68788 (6) 0.70200 (4) 0.0307 (2)
O1 0.24182 (12) 0.73528 (5) 0.83241 (3) 0.03401 (18)
O2 0.87275 (12) 0.52786 (5) 0.67492 (4) 0.0402 (2)
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Atomic displacement parameters (Å2)

U11 U22 U33 U12 U13 U23
C1 0.0401 (7) 0.0291 (5) 0.0482 (7) −0.0040 (5) 0.0204 (6) −0.0039 (5)
C2 0.0318 (6) 0.0266 (5) 0.0337 (6) −0.0005 (4) 0.0013 (5) 0.0007 (4)
C3 0.0318 (6) 0.0241 (5) 0.0255 (5) −0.0043 (4) 0.0004 (5) 0.0029 (4)
C4 0.0289 (6) 0.0273 (5) 0.0251 (5) −0.0027 (4) −0.0007 (4) 0.0015 (4)
C5 0.0320 (6) 0.0283 (5) 0.0357 (6) −0.0042 (5) 0.0018 (5) 0.0048 (4)
C6 0.0398 (7) 0.0218 (5) 0.0375 (6) −0.0016 (5) −0.0023 (5) 0.0023 (4)
C7 0.0332 (6) 0.0264 (5) 0.0310 (6) 0.0034 (4) 0.0003 (5) −0.0002 (4)
C8 0.0289 (6) 0.0249 (5) 0.0245 (5) −0.0005 (4) −0.0013 (4) 0.0006 (4)
C9 0.0293 (6) 0.0266 (5) 0.0262 (5) 0.0016 (5) 0.0004 (5) −0.0035 (4)
C10 0.0403 (7) 0.0347 (6) 0.0480 (7) −0.0067 (5) 0.0162 (6) −0.0078 (5)
C11 0.0302 (6) 0.0337 (5) 0.0282 (5) −0.0001 (5) 0.0037 (5) 0.0020 (4)
C12 0.0330 (6) 0.0295 (5) 0.0299 (5) 0.0017 (5) 0.0008 (5) 0.0009 (4)
C13 0.0255 (6) 0.0297 (5) 0.0310 (5) −0.0031 (4) −0.0036 (5) −0.0033 (4)
C14 0.0294 (6) 0.0325 (5) 0.0404 (6) −0.0010 (5) −0.0008 (5) 0.0025 (4)
C15 0.0402 (7) 0.0439 (7) 0.0424 (7) −0.0079 (6) −0.0013 (6) 0.0104 (5)
C16 0.0349 (7) 0.0544 (7) 0.0351 (6) −0.0136 (6) 0.0054 (6) −0.0025 (5)
C17 0.0264 (6) 0.0450 (7) 0.0494 (7) −0.0017 (5) 0.0039 (6) −0.0128 (5)
C18 0.0297 (6) 0.0315 (6) 0.0444 (7) −0.0004 (5) −0.0007 (5) −0.0013 (5)
C19 0.0294 (6) 0.0292 (5) 0.0429 (6) −0.0006 (5) 0.0083 (5) 0.0054 (5)
C20 0.0228 (5) 0.0304 (5) 0.0320 (5) −0.0024 (5) 0.0068 (5) 0.0071 (4)
C21 0.0263 (6) 0.0406 (6) 0.0323 (6) 0.0000 (5) 0.0018 (5) 0.0084 (4)
C22 0.0376 (7) 0.0416 (6) 0.0314 (5) −0.0076 (5) 0.0043 (5) −0.0013 (5)
C23 0.0416 (7) 0.0297 (6) 0.0443 (7) 0.0022 (5) 0.0132 (6) 0.0028 (5)
C24 0.0311 (6) 0.0396 (6) 0.0433 (7) 0.0069 (5) 0.0001 (5) 0.0101 (5)
C25 0.0289 (6) 0.0364 (6) 0.0335 (6) −0.0028 (5) −0.0015 (5) 0.0031 (5)
N1 0.0295 (5) 0.0247 (4) 0.0270 (4) −0.0009 (4) 0.0019 (4) −0.0001 (3)
N2 0.0297 (5) 0.0268 (4) 0.0370 (5) −0.0031 (4) 0.0034 (4) −0.0014 (4)
N3 0.0300 (5) 0.0277 (4) 0.0345 (5) 0.0021 (4) 0.0052 (4) 0.0030 (4)
O1 0.0351 (4) 0.0253 (3) 0.0416 (4) −0.0049 (3) 0.0136 (4) −0.0037 (3)
O2 0.0407 (5) 0.0283 (4) 0.0515 (5) −0.0052 (4) 0.0187 (4) −0.0111 (3)
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Geometric parameters (Å, °)

C1—O1 1.4503 (14) C12—C13 1.5065 (15)
C1—C2 1.5290 (17) C12—H12A 0.9900
C1—H1A 0.9900 C12—H12B 0.9900
C1—H1B 0.9900 C13—C18 1.3879 (15)
C2—N2 1.4781 (14) C13—C14 1.3899 (14)
C2—C19 1.5211 (15) C14—C15 1.3778 (16)
C2—H2 1.0000 C14—H14 0.9500
C3—N2 1.2660 (14) C15—C16 1.3813 (18)
C3—O1 1.3556 (11) C15—H15 0.9500
C3—C4 1.4790 (14) C16—C17 1.3801 (17)
C4—N1 1.3394 (13) C16—H16 0.9500
C4—C5 1.3905 (14) C17—C18 1.3808 (16)
C5—C6 1.3719 (15) C17—H17 0.9500
C5—H5 0.9500 C18—H18 0.9500
C6—C7 1.3773 (15) C19—C20 1.5078 (14)
C6—H6 0.9500 C19—H19A 0.9900
C7—C8 1.3898 (13) C19—H19B 0.9900
C7—H7 0.9500 C20—C21 1.3852 (15)
C8—N1 1.3415 (13) C20—C25 1.3934 (15)
C8—C9 1.4784 (15) C21—C22 1.3843 (16)
C9—N3 1.2636 (13) C21—H21 0.9500
C9—O2 1.3636 (12) C22—C23 1.3796 (17)
C10—O2 1.4472 (14) C22—H22 0.9500
C10—C11 1.5413 (15) C23—C24 1.3784 (17)
C10—H10A 0.9900 C23—H23 0.9500
C10—H10B 0.9900 C24—C25 1.3806 (15)
C11—N3 1.4796 (14) C24—H24 0.9500
C11—C12 1.5193 (16) C25—H25 0.9500
C11—H11 1.0000
O1—C1—C2 104.10 (8) C11—C12—H12B 109.1
O1—C1—H1A 110.9 H12A—C12—H12B 107.9
C2—C1—H1A 110.9 C18—C13—C14 118.04 (10)
O1—C1—H1B 110.9 C18—C13—C12 120.90 (9)
C2—C1—H1B 110.9 C14—C13—C12 121.05 (10)
H1A—C1—H1B 109.0 C15—C14—C13 120.90 (11)
N2—C2—C19 113.26 (8) C15—C14—H14 119.6
N2—C2—C1 103.54 (9) C13—C14—H14 119.6
C19—C2—C1 112.94 (9) C14—C15—C16 120.44 (11)
N2—C2—H2 109.0 C14—C15—H15 119.8
C19—C2—H2 109.0 C16—C15—H15 119.8
C1—C2—H2 109.0 C17—C16—C15 119.34 (11)
N2—C3—O1 118.92 (10) C17—C16—H16 120.3
N2—C3—C4 124.80 (9) C15—C16—H16 120.3
O1—C3—C4 116.24 (9) C16—C17—C18 120.13 (11)
N1—C4—C5 123.55 (10) C16—C17—H17 119.9
N1—C4—C3 117.18 (8) C18—C17—H17 119.9
C5—C4—C3 119.17 (10) C17—C18—C13 121.14 (10)
C6—C5—C4 118.91 (10) C17—C18—H18 119.4
C6—C5—H5 120.5 C13—C18—H18 119.4
C4—C5—H5 120.5 C20—C19—C2 110.99 (8)
C5—C6—C7 118.60 (9) C20—C19—H19A 109.4
C5—C6—H6 120.7 C2—C19—H19A 109.4
C7—C6—H6 120.7 C20—C19—H19B 109.4
C6—C7—C8 119.11 (10) C2—C19—H19B 109.4
C6—C7—H7 120.4 H19A—C19—H19B 108.0
C8—C7—H7 120.4 C21—C20—C25 118.10 (10)
N1—C8—C7 123.18 (10) C21—C20—C19 121.19 (10)
N1—C8—C9 116.99 (8) C25—C20—C19 120.69 (10)
C7—C8—C9 119.74 (9) C22—C21—C20 121.29 (11)
N3—C9—O2 118.00 (9) C22—C21—H21 119.4
N3—C9—C8 128.02 (9) C20—C21—H21 119.4
O2—C9—C8 113.89 (8) C23—C22—C21 119.90 (11)
O2—C10—C11 103.39 (9) C23—C22—H22 120.1
O2—C10—H10A 111.1 C21—C22—H22 120.1
C11—C10—H10A 111.1 C24—C23—C22 119.52 (11)
O2—C10—H10B 111.1 C24—C23—H23 120.2
C11—C10—H10B 111.1 C22—C23—H23 120.2
H10A—C10—H10B 109.0 C23—C24—C25 120.59 (11)
N3—C11—C12 112.88 (9) C23—C24—H24 119.7
N3—C11—C10 103.36 (8) C25—C24—H24 119.7
C12—C11—C10 114.18 (10) C24—C25—C20 120.60 (11)
N3—C11—H11 108.7 C24—C25—H25 119.7
C12—C11—H11 108.7 C20—C25—H25 119.7
C10—C11—H11 108.7 C4—N1—C8 116.66 (8)
C13—C12—C11 112.38 (9) C3—N2—C2 106.35 (8)
C13—C12—H12A 109.1 C9—N3—C11 106.97 (8)
C11—C12—H12A 109.1 C3—O1—C1 104.79 (8)
C13—C12—H12B 109.1 C9—O2—C10 105.64 (8)
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Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: OM2419).

References

  1. Desimoni, G., Faiti, G. & Quadrelli, P. (2003). Chem. Rev. 103, 3119–3154. [DOI] [PubMed]
  2. Hui, X.-P., Huang, J.-I., Chiou, S.-J. & Gau, H.-M. (2006). J. Chin. Chem. Soc. 53, 421–427.
  3. Meng, J.-C., Fokin, V. V. & Finn, M. G. (2005). Tetrahedron Lett. 46, 4543–4546.
  4. Nesper, R., Pregosin, P. S., Püntener, K. & Wörle, M. (1993). Helv. Chim. Acta, 76, 2239–2249.
  5. Nesper, R., Pregosin, P., Püntener, K., Wörle, M. & Albinati, A. (1996). J Organomet. Chem. 507, 85–101.
  6. Provent, C., Hewage, S., Brand, G., Bernardinelli, G., Charbonnière, L. J. & Williams, A. F. (1997). Angew. Chem. Int. Ed. Engl. 36, 1287–1289.
  7. Schaus, S. E. & Jacobsen, E. N. (2000). Org. Lett. 2, 1001–1004. [DOI] [PubMed]
  8. Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. [DOI] [PubMed]
  9. Stoe & Cie (2005). X-AREA Stoe & Cie, Darmstadt, Germany.
  10. Towers, M. D. K. N., Woodgate, P. D. & Brimble, M. A. (2003). ARKIVOC, pp. 43–55.
  11. Tse, M. K., Bhor, S., Klawonn, M., Anilkumar, G., Jiao, H., Döbler, C., Spannenberg, A., Mägerlein, W., Hugl, H. & Beller, M. (2006). Chem. Eur. J. 12, 1855–1874. [DOI] [PubMed]

Associated Data

This section collects any data citations, data availability statements, or supplementary materials included in this article.

Supplementary Materials

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811014061/om2419sup1.cif

e-67-o1181-sup1.cif (19.3KB, cif)

Structure factors: contains datablocks I. DOI: 10.1107/S1600536811014061/om2419Isup2.hkl

e-67-o1181-Isup2.hkl (266.1KB, hkl)

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Articles from Acta Crystallographica Section E: Structure Reports Online are provided here courtesy of International Union of Crystallography

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