organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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exo-1,7-Di­methyl-4-phenyl-10-oxa-4-aza­tri­cyclo­[5.2.1.02,6]dec-8-ene-3,5-dione

aFacultad de Ciencias Químicas, Universidad de Colima, Km 9 Carretera Colima-Coquimatlán, Apartado Postal 29000, Coquimatlán, Colima, Mexico, and bFacultad de Química, Universidad Nacional Autónoma de México, Ciudad Universitaria, 04510, México D.F., Mexico
*Correspondence e-mail: armandop@ucol.mx

(Received 21 October 2013; accepted 5 November 2013; online 9 November 2013)

The title compound, C16H15NO3, consists of an oxabicycle fused to an N-phenyl-substituted pyrrolidine ring anti to the double bond, affording the exo isomer. In the oxabicycle system, the six-membered ring presents a boat conformation, while the heterocyclic rings show envelope conformations with the O atom projected out of the plane. In the crystal, adjacent mol­ecules are linked via weak C—H⋯O hydrogen bonds, forming chains propagating along the a-axis direction. The chains are linked by C—H⋯π inter­actions, forming two-dimensional networks lying parallel to the ac plane.

Related literature

Monomeric norbornene derivatives synthesized by Diels–Alder reactions have attracted great attention due to the attractive optical, thermal, and electrochemical properties of the resulting polymers, see: Choi et al. (2010[Choi, M.-C., Hwan, J.-C., Kim, C., Kim, Y. & Ha, C.-S. (2010). J. Polym. Sci. Part A Polym. Chem. 48, 5189-5197.]); Khosravi & Al-Hajaji (1998[Khosravi, E. & Al-Hajaji, A. A. (1998). Polymer, 39, 5619-5625.]). For related structures, see: Li (2010[Li, J. (2010). Acta Cryst. E66, o3238.], 2011[Li, J. (2011). Acta Cryst. E67, o588.]); Jarosz et al. (2001[Jarosz, S., Mach, M., Szewczyk, K., Skóra, S. & Ciunik, Z. (2001). Eur. J. Org. Chem. pp. 2955-2964.]).

[Scheme 1]

Experimental

Crystal data
  • C16H15NO3

  • Mr = 269.29

  • Monoclinic, P 21 /c

  • a = 8.1267 (6) Å

  • b = 9.8570 (8) Å

  • c = 17.2099 (12) Å

  • β = 93.564 (7)°

  • V = 1375.93 (18) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 298 K

  • 0.58 × 0.54 × 0.22 mm

Data collection
  • Agilent Xcalibur (Atlas, Gemini) diffractometer

  • Absorption correction: analytical (CrysAlis PRO; Agilent, 2011[Agilent (2011). CrysAlis PRO. Agilent Technologies, Yarnton, England.]) Tmin = 0.958, Tmax = 0.983

  • 6009 measured reflections

  • 2709 independent reflections

  • 2104 reflections with I > 2σ(I)

  • Rint = 0.019

Refinement
  • R[F2 > 2σ(F2)] = 0.040

  • wR(F2) = 0.101

  • S = 1.02

  • 2709 reflections

  • 184 parameters

  • H-atom parameters constrained

  • Δρmax = 0.24 e Å−3

  • Δρmin = −0.16 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

Cg1 is the centroid of the C15–C20 phenyl ring.

D—H⋯A D—H H⋯A DA D—H⋯A
C5—H5⋯O14i 0.93 2.57 3.362 (2) 144
C10—H10BCg1i 0.96 2.95 3.8029 148
C12—H12BCg1ii 0.96 2.79 3.7287 167
Symmetry codes: (i) x-1, y, z; (ii) [x, -y-{\script{1\over 2}}, z-{\script{1\over 2}}].

Data collection: CrysAlis PRO (Agilent, 2011[Agilent (2011). CrysAlis PRO. Agilent Technologies, Yarnton, England.]); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]) and Mercury (Macrae et al., 2008[Macrae, C. F., Bruno, I. J., Chisholm, J. A., Edgington, P. R., McCabe, P., Pidcock, E., Rodriguez-Monge, L., Taylor, R., van de Streek, J. & Wood, P. A. (2008). J. Appl. Cryst. 41, 466-470.]); software used to prepare material for publication: WinGX (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]).

Supporting information


Comment top

Diels-Alder reaction is used to synthesize 5-norbornene-2,3-dicarboximide by reaction between cyclopentadiene and maleic anhydride, followed by imidization with a primary amine (Choi et al., 2010; Khosravi & Al-Hajaji, 1998). However the Diels-Alder adduct is predominantly the endo isomer. In this regard, the use of furan derivatives instead of cyclopentadiene affords the exo isomer at very high yield (Li, 2010, 2011; Jarosz et al., 2001).

X-ray crystallography confirmed the molecular structure and the atom connectivity for the title compound, as illustrated in Fig. 1. The oxabicycle moiety is bound exo with respect to the N-maleimide group. This five-membered imide cycle shows a planar geometry by the contribution of the two carbonyl groups and the sp2 hybridized nitrogen atom N1. This is a consequence of the conjugative delocalization of the nitrogen lone pair, and is supported by the sum of C—N—C angles around N1 of 359.8 (18)°. The phenyl ring (C15···C20) presents a rotation with respect of the plane of the maleimide group, indicated by the torsion angle C20—C15—N1—C2, which is 118.53 (17)°.

Weak hydrogen bonds stabilize the crystal packing by the presence of C—H···O and C—H···π interactions, which are listed in the Table 1. The intermolecular C—H···π contacts involve the C10—H10B···Cg1 and C12—H12B···Cg1 (Cg1 is the centroid of the phenyl ring C15···C20). Moreover, the weak C—H···O interaction formed by C5—H5···O14 propagates along the ac plane (Fig. 2).

Related literature top

Monomeric norbornene derivatives synthesized by Diels–Alder reactions have attracted great attention due to the attractive optical, thermal, and electrochemical properties of the resulting polymers, see: Choi et al. (2010); Khosravi & Al-Hajaji (1998). For related structures, see: Li (2010, 2011); Jarosz et al. (2001).

Experimental top

Diels-Alder adduct was obtained by the reaction between 2,5-dimethylfuran (0.5 g, 5.2 mmol) and N-phenylmaleimide (1.0 g, 5.7 mmol) in ethyl acetate (7.5 ml). The mixture was stirred for 16 h at 333 K. After cooling, the formed precipitate was removed by filtration under vacuum. The collected filtrate was recrystallized twice from ethyl acetate. The title compound was obtained in 86% yield, m.p. 401–403 K. The single-crystal suitable for X-ray determination was obtained by evaporation of an ethyl acetate solution of the title compound over 5 days.

Refinement top

All H atoms were placed in geometrical idealized positions and were refined as riding on their parent atoms, with C—H = 0.93–0.98 Å, and with Uiso(H) = 1.2 Ueq(CH) or 1.5 Ueq(CH3).

Computing details top

Data collection: CrysAlis PRO (Agilent, 2011); cell refinement: CrysAlis PRO (Agilent, 2011); data reduction: CrysAlis PRO (Agilent, 2011); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and Mercury (Macrae et al., 2008); software used to prepare material for publication: WinGX (Farrugia, 2012).

Figures top
[Figure 1] Fig. 1. Molecular structure with displacement ellipsoids for non-H atoms drawn at the 40% probability level.
[Figure 2] Fig. 2. Weak intermolecular hydrogen bond of the title compound viewed down the b axis. The weak C—H···O interactions are showed as dashed lines.
exo-1,7-Dimethyl-4-phenyl-10-oxa-4-azatricyclo[5.2.1.02,6]dec-8-ene-3,5-dione top
Crystal data top
C16H15NO3Dx = 1.3 Mg m3
Mr = 269.29Melting point: 401 K
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
a = 8.1267 (6) ÅCell parameters from 1980 reflections
b = 9.8570 (8) Åθ = 3.4–26.0°
c = 17.2099 (12) ŵ = 0.09 mm1
β = 93.564 (7)°T = 298 K
V = 1375.93 (18) Å3Block, colourless
Z = 40.58 × 0.54 × 0.22 mm
F(000) = 568
Data collection top
Agilent Xcalibur (Atlas, Gemini)
diffractometer
2709 independent reflections
Graphite monochromator2104 reflections with I > 2σ(I)
Detector resolution: 10.4685 pixels mm-1Rint = 0.019
ω scansθmax = 26.1°, θmin = 3.4°
Absorption correction: analytical
(CrysAlis PRO; Agilent, 2011)
h = 109
Tmin = 0.958, Tmax = 0.983k = 1212
6009 measured reflectionsl = 2119
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.040H-atom parameters constrained
wR(F2) = 0.101 w = 1/[σ2(Fo2) + (0.0389P)2 + 0.4058P]
where P = (Fo2 + 2Fc2)/3
S = 1.02(Δ/σ)max = 0.001
2709 reflectionsΔρmax = 0.24 e Å3
184 parametersΔρmin = 0.16 e Å3
0 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
0 constraintsExtinction coefficient: 0.048 (3)
Primary atom site location: structure-invariant direct methods
Crystal data top
C16H15NO3V = 1375.93 (18) Å3
Mr = 269.29Z = 4
Monoclinic, P21/cMo Kα radiation
a = 8.1267 (6) ŵ = 0.09 mm1
b = 9.8570 (8) ÅT = 298 K
c = 17.2099 (12) Å0.58 × 0.54 × 0.22 mm
β = 93.564 (7)°
Data collection top
Agilent Xcalibur (Atlas, Gemini)
diffractometer
2709 independent reflections
Absorption correction: analytical
(CrysAlis PRO; Agilent, 2011)
2104 reflections with I > 2σ(I)
Tmin = 0.958, Tmax = 0.983Rint = 0.019
6009 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0400 restraints
wR(F2) = 0.101H-atom parameters constrained
S = 1.02Δρmax = 0.24 e Å3
2709 reflectionsΔρmin = 0.16 e Å3
184 parameters
Special details top

Experimental. Absorption correction: (CrysAlis PRO; Agilent, 2011) Analytical numeric absorption correction using a multifaceted crystal model

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
C20.89127 (19)0.24866 (16)0.65338 (8)0.0379 (4)
C30.81574 (19)0.27178 (15)0.73016 (8)0.0375 (4)
H30.74820.35420.72960.045*
C40.72028 (18)0.14469 (16)0.75948 (8)0.0372 (4)
C50.6482 (2)0.19228 (18)0.83406 (9)0.0472 (4)
H50.53820.21140.84130.057*
C60.7726 (2)0.20099 (18)0.88640 (9)0.0484 (4)
H60.76760.22790.9380.058*
C70.92630 (19)0.15872 (16)0.84656 (8)0.0386 (4)
C80.96335 (19)0.27970 (16)0.79084 (8)0.0379 (4)
H80.96880.3670.81810.045*
C91.1131 (2)0.25456 (16)0.74554 (9)0.0393 (4)
C100.6092 (2)0.06732 (19)0.70213 (9)0.0486 (4)
H10A0.67260.0330.66120.073*
H10B0.52450.12650.68050.073*
H10C0.55970.0070.72810.073*
C121.0660 (2)0.0990 (2)0.89652 (9)0.0533 (5)
H12A1.0270.0220.92420.08*
H12B1.10840.16580.9330.08*
H12C1.15190.07080.86420.08*
C151.17344 (18)0.21261 (16)0.60751 (8)0.0377 (4)
C161.1598 (2)0.09518 (17)0.56431 (9)0.0478 (4)
H161.0780.03220.57340.057*
C171.2689 (2)0.07181 (19)0.50718 (10)0.0556 (5)
H171.26030.00720.47760.067*
C181.3896 (2)0.1645 (2)0.49394 (10)0.0543 (5)
H181.46290.14820.45560.065*
C191.4025 (2)0.2812 (2)0.53705 (10)0.0521 (5)
H191.48480.34370.5280.063*
C201.29349 (19)0.30661 (18)0.59406 (9)0.0442 (4)
H201.30140.38630.62290.053*
O110.85844 (12)0.06324 (10)0.78944 (5)0.0362 (3)
O130.82053 (14)0.24123 (13)0.58982 (6)0.0525 (3)
O141.25472 (14)0.24824 (14)0.77023 (7)0.0556 (4)
N11.06138 (15)0.23679 (13)0.66731 (7)0.0381 (3)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C20.0386 (8)0.0413 (8)0.0339 (8)0.0014 (7)0.0028 (6)0.0026 (7)
C30.0374 (8)0.0387 (8)0.0365 (8)0.0073 (7)0.0044 (6)0.0010 (6)
C40.0337 (8)0.0440 (9)0.0340 (7)0.0042 (7)0.0029 (6)0.0002 (7)
C50.0426 (9)0.0590 (10)0.0413 (9)0.0037 (8)0.0123 (7)0.0020 (8)
C60.0583 (11)0.0552 (10)0.0332 (8)0.0037 (9)0.0136 (7)0.0068 (7)
C70.0443 (9)0.0430 (9)0.0284 (7)0.0022 (7)0.0001 (6)0.0049 (6)
C80.0444 (9)0.0363 (8)0.0332 (7)0.0005 (7)0.0041 (6)0.0068 (6)
C90.0407 (9)0.0407 (8)0.0363 (8)0.0026 (7)0.0006 (7)0.0007 (7)
C100.0407 (9)0.0615 (11)0.0430 (9)0.0035 (8)0.0035 (7)0.0006 (8)
C120.0558 (11)0.0633 (12)0.0390 (9)0.0051 (9)0.0111 (8)0.0054 (8)
C150.0360 (8)0.0449 (9)0.0326 (7)0.0037 (7)0.0046 (6)0.0018 (7)
C160.0544 (10)0.0455 (9)0.0448 (9)0.0038 (8)0.0129 (8)0.0010 (8)
C170.0689 (12)0.0526 (11)0.0469 (10)0.0084 (10)0.0167 (9)0.0054 (8)
C180.0504 (11)0.0691 (13)0.0454 (9)0.0155 (9)0.0176 (8)0.0068 (9)
C190.0401 (9)0.0626 (12)0.0544 (10)0.0001 (8)0.0095 (8)0.0137 (9)
C200.0397 (9)0.0474 (9)0.0457 (9)0.0005 (8)0.0038 (7)0.0006 (8)
O110.0379 (6)0.0376 (6)0.0327 (5)0.0011 (5)0.0021 (4)0.0027 (4)
O130.0456 (7)0.0792 (9)0.0323 (6)0.0025 (6)0.0016 (5)0.0041 (6)
O140.0395 (7)0.0805 (9)0.0462 (7)0.0041 (6)0.0029 (5)0.0001 (6)
N10.0358 (7)0.0472 (8)0.0317 (6)0.0004 (6)0.0051 (5)0.0022 (5)
Geometric parameters (Å, º) top
C2—O131.2059 (18)C9—N11.3962 (19)
C2—N11.3932 (19)C10—H10A0.96
C2—C31.508 (2)C10—H10B0.96
C3—C81.543 (2)C10—H10C0.96
C3—C41.573 (2)C12—H12A0.96
C3—H30.98C12—H12B0.96
C4—O111.4488 (17)C12—H12C0.96
C4—C101.503 (2)C15—C201.375 (2)
C4—C51.518 (2)C15—C161.376 (2)
C5—C61.314 (2)C15—N11.4359 (18)
C5—H50.93C16—C171.384 (2)
C6—C71.520 (2)C16—H160.93
C6—H60.93C17—C181.370 (3)
C7—O111.4454 (17)C17—H170.93
C7—C121.501 (2)C18—C191.369 (3)
C7—C81.571 (2)C18—H180.93
C8—C91.506 (2)C19—C201.385 (2)
C8—H80.98C19—H190.93
C9—O141.2036 (19)C20—H200.93
O13—C2—N1124.26 (14)N1—C9—C8108.39 (13)
O13—C2—C3127.35 (14)C4—C10—H10A109.5
N1—C2—C3108.39 (12)C4—C10—H10B109.5
C2—C3—C8105.01 (12)H10A—C10—H10B109.5
C2—C3—C4113.35 (12)C4—C10—H10C109.5
C8—C3—C4101.62 (11)H10A—C10—H10C109.5
C2—C3—H3112.1H10B—C10—H10C109.5
C8—C3—H3112.1C7—C12—H12A109.5
C4—C3—H3112.1C7—C12—H12B109.5
O11—C4—C10111.89 (13)H12A—C12—H12B109.5
O11—C4—C5101.62 (11)C7—C12—H12C109.5
C10—C4—C5117.68 (13)H12A—C12—H12C109.5
O11—C4—C399.72 (11)H12B—C12—H12C109.5
C10—C4—C3118.77 (12)C20—C15—C16120.66 (14)
C5—C4—C3104.42 (13)C20—C15—N1119.79 (14)
C6—C5—C4106.20 (14)C16—C15—N1119.55 (14)
C6—C5—H5126.9C15—C16—C17119.34 (16)
C4—C5—H5126.9C15—C16—H16120.3
C5—C6—C7106.95 (14)C17—C16—H16120.3
C5—C6—H6126.5C18—C17—C16120.28 (17)
C7—C6—H6126.5C18—C17—H17119.9
O11—C7—C12112.15 (13)C16—C17—H17119.9
O11—C7—C6101.30 (12)C19—C18—C17120.12 (16)
C12—C7—C6117.55 (13)C19—C18—H18119.9
O11—C7—C899.13 (11)C17—C18—H18119.9
C12—C7—C8118.73 (14)C18—C19—C20120.32 (17)
C6—C7—C8105.15 (13)C18—C19—H19119.8
C9—C8—C3105.10 (12)C20—C19—H19119.8
C9—C8—C7112.51 (13)C15—C20—C19119.28 (16)
C3—C8—C7101.79 (12)C15—C20—H20120.4
C9—C8—H8112.3C19—C20—H20120.4
C3—C8—H8112.3C7—O11—C497.80 (11)
C7—C8—H8112.3C2—N1—C9113.03 (12)
O14—C9—N1123.91 (14)C2—N1—C15123.87 (12)
O14—C9—C8127.69 (14)C9—N1—C15123.07 (13)
O13—C2—C3—C8177.05 (16)C3—C8—C9—N11.13 (16)
N1—C2—C3—C82.91 (16)C7—C8—C9—N1111.06 (14)
O13—C2—C3—C472.9 (2)C20—C15—C16—C170.4 (2)
N1—C2—C3—C4107.14 (14)N1—C15—C16—C17179.47 (15)
C2—C3—C4—O1178.04 (14)C15—C16—C17—C180.2 (3)
C8—C3—C4—O1134.09 (12)C16—C17—C18—C190.3 (3)
C2—C3—C4—C1043.66 (18)C17—C18—C19—C200.2 (3)
C8—C3—C4—C10155.80 (13)C16—C15—C20—C190.8 (2)
C2—C3—C4—C5177.18 (13)N1—C15—C20—C19179.01 (14)
C8—C3—C4—C570.69 (14)C18—C19—C20—C150.7 (2)
O11—C4—C5—C630.57 (17)C12—C7—O11—C4173.54 (12)
C10—C4—C5—C6153.10 (16)C6—C7—O11—C447.34 (13)
C3—C4—C5—C672.78 (16)C8—C7—O11—C460.23 (12)
C4—C5—C6—C70.22 (19)C10—C4—O11—C7174.15 (12)
C5—C6—C7—O1130.23 (17)C5—C4—O11—C747.72 (13)
C5—C6—C7—C12152.76 (16)C3—C4—O11—C759.33 (12)
C5—C6—C7—C872.58 (17)O13—C2—N1—C9177.59 (15)
C2—C3—C8—C92.40 (16)C3—C2—N1—C92.37 (18)
C4—C3—C8—C9115.90 (12)O13—C2—N1—C150.8 (3)
C2—C3—C8—C7119.87 (12)C3—C2—N1—C15179.28 (13)
C4—C3—C8—C71.57 (13)O14—C9—N1—C2179.87 (15)
O11—C7—C8—C975.16 (14)C8—C9—N1—C20.75 (18)
C12—C7—C8—C946.41 (18)O14—C9—N1—C151.8 (2)
C6—C7—C8—C9179.58 (12)C8—C9—N1—C15179.11 (13)
O11—C7—C8—C336.83 (13)C20—C15—N1—C2118.53 (17)
C12—C7—C8—C3158.40 (13)C16—C15—N1—C261.6 (2)
C6—C7—C8—C367.59 (14)C20—C15—N1—C959.6 (2)
C3—C8—C9—O14177.95 (16)C16—C15—N1—C9120.18 (17)
C7—C8—C9—O1468.0 (2)
Hydrogen-bond geometry (Å, º) top
Cg1 is the centroid of the C15–C20 phenyl ring.
D—H···AD—HH···AD···AD—H···A
C5—H5···O14i0.932.573.362 (2)144
C10—H10B···Cg1i0.962.953.8029148
C12—H12B···Cg1ii0.962.793.7287167
Symmetry codes: (i) x1, y, z; (ii) x, y1/2, z1/2.
Hydrogen-bond geometry (Å, º) top
Cg1 is the centroid of the C15–C20 phenyl ring.
D—H···AD—HH···AD···AD—H···A
C5—H5···O14i0.932.573.362 (2)144
C10—H10B···Cg1i0.962.953.8029148
C12—H12B···Cg1ii0.962.793.7287167
Symmetry codes: (i) x1, y, z; (ii) x, y1/2, z1/2.
 

Footnotes

Alternative author for correspondence, e-mail: oscar_vazquez@ucol.mx.

References

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