organic compounds
trans-1-Phenylpyrrolidine-2,5-dicarbonitrile
aLudwig-Maximilians-Universität, Department, Butenandtstrasse 5–13, 81377 München, Germany
*Correspondence e-mail: pemay@cup.uni-muenchen.de
In the title compound, C12H11N3, the plane of the phenyl ring and the least-squares plane of the pyrrolidine ring enclose an angle of 14.30 (6)°. The intracyclic N atom features a nearly trigonal-planar coordination geometry due to π-interactions with the aromatic system. The pyrrolidine ring is present in a twist conformation for which the closest pucker descriptor is C9TC8. Weak intermolecular C—H⋯N and C—H⋯π contacts occur
Related literature
For background to the synthesis, see: Han & Ofial (2009); Takahashi et al. (1986). For a related structure, see: Menezes et al. (2007). For puckering analysis, see: Cremer & Pople (1975).
Experimental
Crystal data
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Data collection
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Refinement
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Data collection: COLLECT (Hooft, 2004); cell SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO (Otwinowski & Minor, 1997) and SCALEPACK; program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: PLATON (Spek, 2009).
Supporting information
https://doi.org/10.1107/S1600536810001479/fl2285sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810001479/fl2285Isup2.hkl
Under an atmosphere of dry nitrogen, a 25 ml Schlenk flask was charged with FeCl2 (10 mol-/%, 13 mg). Then N-phenylpyrrolidine (1.0 mmol), trimethylsilyl cyanide (4.0 mmol, 0.54 ml), and MeOH (2.0 ml) were added successively by syringe. To the mixture was added dropwise tert-butylhydroperoxide (2.5 mmol, 0.470 ml, 5.5 M solution in decane) over a period of 5 minutes. The mixture was stirred at room temperature for 24 h. Subsequently, the reaction mixture was poured into a saturated aqueous NaCl solution (20 ml) and extracted with dichloromethane (three times 20 ml). The organic phases were combined, and the volatile components were evaporated in a rotary evaporator. After
on silica gel (n-pentane/diethyl ether = 3:1, v/v), 1-phenylpyrrolidine-2,5-dicarbonitrile was isolated as a colorless solid (54%) [Han et al. (2009)].The title compound (50 mg) was dissolved in 2 ml of a mixture of dichloromethane/n-pentane/ethyl ether mixture (2/1/1, v/v/v). The solvent was allowed to evaporate slowly at room temperature. The thus formed crystals were suitable for X-ray analysis. mp 149–151 °C ([Takahashi et al. (1986)], mp 161.5–163 °C (from ethanol)).
All H atoms were found in difference maps. The H atoms were positioned geometrically (bond distances for phenyl-CH: 0.95 Å, for aliphatic CH: 1.00 Å, for aliphatic CH2: 0.99 Å) and treated as riding on their parent atoms [Uiso(H) = 1.2Ueq(C)].
Under oxidative conditions, iron salts activate C(sp3)-H bonds adjacent to the nitrogen atom of tertiary
Hence the cross-coupling reactions of a variety of tertiary with cyanide were enabled in the presence of tert-butylhydroperoxide. Performing the reaction in the presence of 4 equivalents of trimethylsilyl cyanide allowed the twofold cyanation of N-phenylpyrrolidine [Han et al. (2009)].The
of (I) contains one complete molecule which is shown in Figure 1. The plane of the phenyl ring and the least-square plane of the pyrrolidine ring enclose an angle of 14.30 (6)°, which is quite similar to the angle found in a related structure of 1,2-Dichloro-4-(pyrrolidino)-5-nitrobenzene (18.69 (14)°, Menezes et al. (2007)).The intracyclic nitrogen atom is nearly in the plane defined by the three carbon atoms bonded to it. The displacement of the nitrogen atom from the plane is only 0.073 (1) Å. The planarization of the nitrogen atom may be rationalized by possible π-interaction of the lone pair with the aromatic system.
The pyrrolidine ring is present in a twist-conformation for which the closest pucker descriptor is C9TC8 [Cremer et al. (1975)]. This conformation is slightly distorted towards an envelope-conformation EC8. In a related structure [Menezes et al. (2007)], the ring is twisted along the same bond, however, in the other direction (C8TC9).
Both carbonitrile nitrogen atoms act as acceptors in very weak contacts of the type C–H···N. Furthermore the packing features very weak C–H···π contacts with the phenyl π-system as acceptor. The packing of the title compound is shown in Figure 2.
For background to the synthesis, see: Han et al. (2009); Takahashi et al. (1986). For a related structure, see: Menezes et al. (2007). For puckering analysis, see: Cremer et al. (1975).
Data collection: COLLECT (Hooft, 2004); cell
SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO and SCALEPACK (Otwinowski & Minor, 1997); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: PLATON (Spek, 2009).Fig. 1. The molecular structure of the title compound, with atom labels and anisotropic displacement ellipsoids (drawn at 50% probability level) for non-H atoms. | |
Fig. 2. The packing of the title compound viewed along [-100]. |
C12H11N3 | F(000) = 832 |
Mr = 197.24 | Dx = 1.243 (1) Mg m−3 |
Orthorhombic, Pbca | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ac 2ab | Cell parameters from 9019 reflections |
a = 9.1807 (1) Å | θ = 3.1–27.5° |
b = 14.5693 (2) Å | µ = 0.08 mm−1 |
c = 15.7576 (2) Å | T = 200 K |
V = 2107.68 (5) Å3 | Block, colourless |
Z = 8 | 0.33 × 0.18 × 0.15 mm |
Nonius KappaCCD diffractometer | 2109 reflections with I > 2σ(I) |
Radiation source: rotating anode | Rint = 0.022 |
MONTEL, graded multilayered X-ray optics monochromator | θmax = 27.5°, θmin = 3.4° |
Detector resolution: 9 pixels mm-1 | h = −11→11 |
CCD; rotation images; thick slices, phi/ω–scan | k = −18→18 |
16161 measured reflections | l = −20→20 |
2413 independent reflections |
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)] = 0.039 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.107 | H-atom parameters constrained |
S = 1.06 | w = 1/[σ2(Fo2) + (0.049P)2 + 0.5393P] where P = (Fo2 + 2Fc2)/3 |
2413 reflections | (Δ/σ)max < 0.001 |
136 parameters | Δρmax = 0.14 e Å−3 |
0 restraints | Δρmin = −0.18 e Å−3 |
C12H11N3 | V = 2107.68 (5) Å3 |
Mr = 197.24 | Z = 8 |
Orthorhombic, Pbca | Mo Kα radiation |
a = 9.1807 (1) Å | µ = 0.08 mm−1 |
b = 14.5693 (2) Å | T = 200 K |
c = 15.7576 (2) Å | 0.33 × 0.18 × 0.15 mm |
Nonius KappaCCD diffractometer | 2109 reflections with I > 2σ(I) |
16161 measured reflections | Rint = 0.022 |
2413 independent reflections |
R[F2 > 2σ(F2)] = 0.039 | 0 restraints |
wR(F2) = 0.107 | H-atom parameters constrained |
S = 1.06 | Δρmax = 0.14 e Å−3 |
2413 reflections | Δρmin = −0.18 e Å−3 |
136 parameters |
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 > 2σ(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. |
x | y | z | Uiso*/Ueq | ||
N1 | 0.91889 (10) | 0.12762 (7) | 0.48710 (6) | 0.0339 (2) | |
N2 | 0.63244 (13) | 0.15665 (9) | 0.34906 (8) | 0.0515 (3) | |
N3 | 1.27530 (11) | 0.14135 (8) | 0.55151 (7) | 0.0460 (3) | |
C1 | 0.84192 (11) | 0.11277 (7) | 0.56211 (6) | 0.0289 (2) | |
C2 | 0.71584 (12) | 0.05831 (8) | 0.56245 (7) | 0.0331 (3) | |
H2 | 0.6806 | 0.0329 | 0.5109 | 0.040* | |
C3 | 0.64254 (13) | 0.04149 (8) | 0.63784 (8) | 0.0395 (3) | |
H3 | 0.5569 | 0.0049 | 0.6373 | 0.047* | |
C4 | 0.69229 (13) | 0.07717 (9) | 0.71358 (8) | 0.0414 (3) | |
H4 | 0.6423 | 0.0647 | 0.7651 | 0.050* | |
C5 | 0.81566 (13) | 0.13119 (9) | 0.71352 (7) | 0.0393 (3) | |
H5 | 0.8501 | 0.1561 | 0.7655 | 0.047* | |
C6 | 0.89031 (12) | 0.14984 (8) | 0.63898 (7) | 0.0338 (3) | |
H6 | 0.9744 | 0.1878 | 0.6401 | 0.041* | |
C7 | 0.87833 (12) | 0.08771 (7) | 0.40605 (6) | 0.0313 (2) | |
H7 | 0.8707 | 0.0195 | 0.4112 | 0.038* | |
C8 | 1.00567 (13) | 0.11327 (8) | 0.34813 (7) | 0.0385 (3) | |
H8A | 1.0857 | 0.0680 | 0.3527 | 0.046* | |
H8B | 0.9742 | 0.1176 | 0.2882 | 0.046* | |
C9 | 1.05183 (14) | 0.20663 (8) | 0.38243 (8) | 0.0405 (3) | |
H9A | 0.9888 | 0.2561 | 0.3598 | 0.049* | |
H9B | 1.1544 | 0.2202 | 0.3676 | 0.049* | |
C10 | 1.03301 (11) | 0.19671 (7) | 0.47859 (7) | 0.0326 (3) | |
H10 | 1.0003 | 0.2562 | 0.5038 | 0.039* | |
C11 | 0.73934 (13) | 0.12635 (8) | 0.37363 (7) | 0.0349 (3) | |
C12 | 1.16995 (12) | 0.16549 (7) | 0.51982 (7) | 0.0342 (3) |
U11 | U22 | U33 | U12 | U13 | U23 | |
N1 | 0.0323 (5) | 0.0433 (5) | 0.0262 (5) | −0.0116 (4) | 0.0000 (4) | 0.0001 (4) |
N2 | 0.0473 (7) | 0.0588 (7) | 0.0483 (6) | 0.0060 (5) | −0.0134 (5) | −0.0106 (5) |
N3 | 0.0382 (6) | 0.0456 (6) | 0.0542 (7) | −0.0001 (5) | −0.0083 (5) | −0.0055 (5) |
C1 | 0.0275 (5) | 0.0320 (5) | 0.0270 (5) | 0.0013 (4) | −0.0005 (4) | 0.0025 (4) |
C2 | 0.0315 (6) | 0.0356 (6) | 0.0321 (5) | −0.0039 (4) | 0.0000 (4) | −0.0001 (4) |
C3 | 0.0342 (6) | 0.0412 (6) | 0.0432 (6) | −0.0030 (5) | 0.0068 (5) | 0.0056 (5) |
C4 | 0.0421 (7) | 0.0493 (7) | 0.0327 (6) | 0.0067 (5) | 0.0094 (5) | 0.0067 (5) |
C5 | 0.0426 (7) | 0.0476 (6) | 0.0277 (5) | 0.0067 (5) | −0.0022 (5) | −0.0020 (5) |
C6 | 0.0311 (6) | 0.0391 (6) | 0.0311 (6) | 0.0004 (4) | −0.0027 (4) | −0.0014 (4) |
C7 | 0.0351 (6) | 0.0322 (5) | 0.0267 (5) | −0.0007 (4) | 0.0003 (4) | 0.0000 (4) |
C8 | 0.0388 (6) | 0.0453 (7) | 0.0315 (6) | 0.0038 (5) | 0.0070 (5) | 0.0045 (5) |
C9 | 0.0384 (6) | 0.0427 (6) | 0.0405 (6) | −0.0041 (5) | 0.0031 (5) | 0.0128 (5) |
C10 | 0.0290 (5) | 0.0310 (5) | 0.0379 (6) | −0.0032 (4) | 0.0005 (4) | 0.0036 (4) |
C11 | 0.0387 (6) | 0.0369 (6) | 0.0289 (5) | −0.0030 (5) | −0.0031 (5) | −0.0057 (4) |
C12 | 0.0328 (6) | 0.0312 (5) | 0.0388 (6) | −0.0052 (4) | 0.0003 (5) | −0.0022 (4) |
N1—C1 | 1.3939 (13) | C5—H5 | 0.9500 |
N1—C7 | 1.4519 (14) | C6—H6 | 0.9500 |
N1—C10 | 1.4591 (13) | C7—C11 | 1.4853 (16) |
N2—C11 | 1.1437 (16) | C7—C8 | 1.5291 (15) |
N3—C12 | 1.1438 (16) | C7—H7 | 1.0000 |
C1—C6 | 1.3987 (15) | C8—C9 | 1.5238 (17) |
C1—C2 | 1.4034 (15) | C8—H8A | 0.9900 |
C2—C3 | 1.3873 (15) | C8—H8B | 0.9900 |
C2—H2 | 0.9500 | C9—C10 | 1.5320 (16) |
C3—C4 | 1.3796 (18) | C9—H9A | 0.9900 |
C3—H3 | 0.9500 | C9—H9B | 0.9900 |
C4—C5 | 1.3791 (18) | C10—C12 | 1.4864 (15) |
C4—H4 | 0.9500 | C10—H10 | 1.0000 |
C5—C6 | 1.3868 (16) | ||
C1—N1—C7 | 123.63 (9) | N1—C7—H7 | 110.2 |
C1—N1—C10 | 123.29 (9) | C11—C7—H7 | 110.2 |
C7—N1—C10 | 112.31 (8) | C8—C7—H7 | 110.2 |
N1—C1—C6 | 120.89 (10) | C9—C8—C7 | 102.62 (9) |
N1—C1—C2 | 120.60 (9) | C9—C8—H8A | 111.2 |
C6—C1—C2 | 118.49 (10) | C7—C8—H8A | 111.2 |
C3—C2—C1 | 120.22 (10) | C9—C8—H8B | 111.2 |
C3—C2—H2 | 119.9 | C7—C8—H8B | 111.2 |
C1—C2—H2 | 119.9 | H8A—C8—H8B | 109.2 |
C4—C3—C2 | 120.91 (11) | C8—C9—C10 | 103.60 (9) |
C4—C3—H3 | 119.5 | C8—C9—H9A | 111.0 |
C2—C3—H3 | 119.5 | C10—C9—H9A | 111.0 |
C5—C4—C3 | 119.10 (11) | C8—C9—H9B | 111.0 |
C5—C4—H4 | 120.5 | C10—C9—H9B | 111.0 |
C3—C4—H4 | 120.5 | H9A—C9—H9B | 109.0 |
C4—C5—C6 | 121.22 (11) | N1—C10—C12 | 110.86 (9) |
C4—C5—H5 | 119.4 | N1—C10—C9 | 103.71 (9) |
C6—C5—H5 | 119.4 | C12—C10—C9 | 111.46 (9) |
C5—C6—C1 | 120.06 (11) | N1—C10—H10 | 110.2 |
C5—C6—H6 | 120.0 | C12—C10—H10 | 110.2 |
C1—C6—H6 | 120.0 | C9—C10—H10 | 110.2 |
N1—C7—C11 | 111.78 (9) | N2—C11—C7 | 179.49 (13) |
N1—C7—C8 | 103.38 (9) | N3—C12—C10 | 179.91 (15) |
C11—C7—C8 | 111.05 (9) | ||
C7—N1—C1—C6 | 177.08 (10) | C10—N1—C7—C11 | −102.29 (11) |
C10—N1—C1—C6 | −13.76 (16) | C1—N1—C7—C8 | −172.55 (10) |
C7—N1—C1—C2 | −1.36 (16) | C10—N1—C7—C8 | 17.22 (12) |
C10—N1—C1—C2 | 167.81 (10) | N1—C7—C8—C9 | −33.54 (11) |
N1—C1—C2—C3 | 177.94 (10) | C11—C7—C8—C9 | 86.48 (11) |
C6—C1—C2—C3 | −0.53 (16) | C7—C8—C9—C10 | 37.66 (11) |
C1—C2—C3—C4 | −0.45 (18) | C1—N1—C10—C12 | 76.32 (13) |
C2—C3—C4—C5 | 0.83 (18) | C7—N1—C10—C12 | −113.42 (10) |
C3—C4—C5—C6 | −0.22 (18) | C1—N1—C10—C9 | −163.96 (10) |
C4—C5—C6—C1 | −0.78 (18) | C7—N1—C10—C9 | 6.30 (12) |
N1—C1—C6—C5 | −177.33 (10) | C8—C9—C10—N1 | −27.35 (12) |
C2—C1—C6—C5 | 1.14 (16) | C8—C9—C10—C12 | 91.97 (11) |
C1—N1—C7—C11 | 67.93 (13) |
Cg is the centroid of the C1–C6 ring. |
D—H···A | D—H | H···A | D···A | D—H···A |
C6—H6···N2i | 0.95 | 2.70 | 3.5952 (17) | 158 |
C8—H8B···N2ii | 0.99 | 2.67 | 3.3777 (17) | 129 |
C10—H10···N3iii | 1.00 | 2.69 | 3.3748 (15) | 126 |
C8—H8A···Cgi | 0.99 | 2.74 | 3.6937 (13) | 162 |
C9—H9B···Cgiv | 0.99 | 2.88 | 3.5111 (13) | 122 |
Symmetry codes: (i) x+1/2, −y+1/2, −z+1; (ii) x+1/2, y, −z+1/2; (iii) x−1/2, −y+1/2, −z+1; (iv) −x+2, −y, −z+1. |
Experimental details
Crystal data | |
Chemical formula | C12H11N3 |
Mr | 197.24 |
Crystal system, space group | Orthorhombic, Pbca |
Temperature (K) | 200 |
a, b, c (Å) | 9.1807 (1), 14.5693 (2), 15.7576 (2) |
V (Å3) | 2107.68 (5) |
Z | 8 |
Radiation type | Mo Kα |
µ (mm−1) | 0.08 |
Crystal size (mm) | 0.33 × 0.18 × 0.15 |
Data collection | |
Diffractometer | Nonius KappaCCD |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 16161, 2413, 2109 |
Rint | 0.022 |
(sin θ/λ)max (Å−1) | 0.649 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.039, 0.107, 1.06 |
No. of reflections | 2413 |
No. of parameters | 136 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.14, −0.18 |
Computer programs: COLLECT (Hooft, 2004), DENZO and SCALEPACK (Otwinowski & Minor, 1997), SIR97 (Altomare et al., 1999), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997), PLATON (Spek, 2009).
Cg is the centroid of the C1–C6 ring. |
D—H···A | D—H | H···A | D···A | D—H···A |
C6—H6···N2i | 0.95 | 2.70 | 3.5952 (17) | 158 |
C8—H8B···N2ii | 0.99 | 2.67 | 3.3777 (17) | 129 |
C10—H10···N3iii | 1.00 | 2.69 | 3.3748 (15) | 126 |
C8—H8A···Cgi | 0.99 | 2.74 | 3.6937 (13) | 162 |
C9—H9B···Cgiv | 0.99 | 2.88 | 3.5111 (13) | 122 |
Symmetry codes: (i) x+1/2, −y+1/2, −z+1; (ii) x+1/2, y, −z+1/2; (iii) x−1/2, −y+1/2, −z+1; (iv) −x+2, −y, −z+1. |
Acknowledgements
We thank the Chinese Scholarship Council for a fellowship (to WH) and Professor Herbert Mayr for continuous support.
References
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Under oxidative conditions, iron salts activate C(sp3)-H bonds adjacent to the nitrogen atom of tertiary amines. Hence the cross-coupling reactions of a variety of tertiary amines with cyanide were enabled in the presence of tert-butylhydroperoxide. Performing the reaction in the presence of 4 equivalents of trimethylsilyl cyanide allowed the twofold cyanation of N-phenylpyrrolidine [Han et al. (2009)].
The asymmetric unit of (I) contains one complete molecule which is shown in Figure 1. The plane of the phenyl ring and the least-square plane of the pyrrolidine ring enclose an angle of 14.30 (6)°, which is quite similar to the angle found in a related structure of 1,2-Dichloro-4-(pyrrolidino)-5-nitrobenzene (18.69 (14)°, Menezes et al. (2007)).
The intracyclic nitrogen atom is nearly in the plane defined by the three carbon atoms bonded to it. The displacement of the nitrogen atom from the plane is only 0.073 (1) Å. The planarization of the nitrogen atom may be rationalized by possible π-interaction of the lone pair with the aromatic system.
The pyrrolidine ring is present in a twist-conformation for which the closest pucker descriptor is C9TC8 [Cremer et al. (1975)]. This conformation is slightly distorted towards an envelope-conformation EC8. In a related structure [Menezes et al. (2007)], the ring is twisted along the same bond, however, in the other direction (C8TC9).
Both carbonitrile nitrogen atoms act as acceptors in very weak contacts of the type C–H···N. Furthermore the packing features very weak C–H···π contacts with the phenyl π-system as acceptor. The packing of the title compound is shown in Figure 2.