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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 70| Part 9| September 2014| Pages o942-o943

Crystal structure of 1,3-di­methyl-3-phenyl­pyrrolidine-2,5-dione: a clinically used anti­convulsant

aDepartment of Chemistry & Biology, New Mexico Highlands University, 803 University Avenue, Las Vegas, NM 87701, USA, bDepartment of Engineering Photonics, St Petersburg National Research University of Information Technologies, Mechanics and Optics (ITMO University), 49 Kronverkskiy Avenue, St Petersburg 197101, Russian Federation, and cX-Ray Structural Centre, A.N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, 28 Vavilov Street, B-334, Moscow 119991, Russian Federation
*Correspondence e-mail: carloso14@msn.com

Edited by H. Stoeckli-Evans, University of Neuchâtel, Switzerland (Received 12 July 2014; accepted 18 July 2014; online 1 August 2014)

In the title compound, C12H13NO2, the five-membered ring has an envelope conformation; the disubstituted C atom lies out of the mean plane through the four other ring atoms (r.m.s. deviation = 0.0038 Å) by 0.1877 (18) Å. The plane of the phenyl substituent is practically perpendicular to that of the planar part of the five-membered ring, with a dihedral angle of 87.01 (5)°. In the crystal, mol­ecules are linked by weak C—H⋯O hydrogen bonds, forming inversion dimers. The dimers are linked by further C—H⋯O hydrogen bonds, as well as carbon­yl–carbonyl attractive inter­actions [O⋯C = 3.2879 (19) Å], forming a three-dimensional framework structure.

1. Related literature

For general background to the properties of α-substituted cyclic imides, see: Chen et al. (1951[Chen, G., Portman, R., Ensor, C. R. & Bratton, A. C. (1951). J. Pharmacol. Exp. Ther. 103, 54-61.], 2014[Chen, Y., Timofeeva, T. V., Huang, J., Ordonez, C. & Krivoshein, A. V. (2014). Methsuximide and N-desmethylmethsuximide: From crystal structures to pharmacological activity, Neuroscience 2014, Washington, USA, Book of Abstracts.]); Vida & Gerry (1977[Vida, J. A. & Gerry, E. H. (1977). Cyclic ureides. In: Anticonvulsants, edited by J. A. Vida, pp. 151-173. New York: Academic Press.]); Kuhnert-Brandstätter & Bösch (1978[Kuhnert-Brandstätter, M. & Bösch, L. (1978). Arch. Pharm. (Weinheim), 311, 757-761.]); Sigler et al. (2001[Sigler, M., Strassburg, H. M. & Boenigk, H. E. (2001). Seizure, 10, 120-124.]); Lin et al. (2012[Lin, P.-C., Su, C.-S., Tang, M. & Chen, Y.-P. (2012). J. Supercrit. Fluids, 72, 84-89.]). For the crystal structures of some succinimide derivatives, see: Argay & Carstensen-Oeser (1973[Argay, G. & Carstensen-Oeser, E. (1973). Acta Cryst. B29, 1186-1190.]); Argay & Kálmán (1973[Argay, G. & Kálmán, A. (1973). Acta Cryst. B29, 636-638.]); Argay & Seres (1973[Argay, G. & Seres, J. (1973). Acta Cryst. B29, 1146-1149.]); Kwiatkowski & Karolak-Wojciechowska (1992[Kwiatkowski, W. & Karolak-Wojciechowska, J. (1992). Acta Cryst. C48, 206-208.]); Khrustalev et al. (2014[Khrustalev, V. N., Sandhu, B., Bentum, S., Fonari, A., Krivoshein, A. V. & Timofeeva, T. V. (2014). Cryst. Growth & Des. 14, 3360-3369.]). For carbon­yl–carbonyl inter­actions, see: Allen et al. (1998[Allen, F. H., Baalham, C. A., Lommerse, J. P. M. & Raithby, P. R. (1998). Acta Cryst. B54, 320-329.]).

[Scheme 1]

2. Experimental

2.1. Crystal data

  • C12H13NO2

  • Mr = 203.23

  • Monoclinic, P 21 /c

  • a = 10.517 (5) Å

  • b = 7.383 (3) Å

  • c = 13.568 (6) Å

  • β = 102.332 (6)°

  • V = 1029.2 (8) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 100 K

  • 0.45 × 0.35 × 0.25 mm

2.2. Data collection

  • Bruker SMART APEXII CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2005[Bruker (2005). SADABS, APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.961, Tmax = 0.978

  • 11948 measured reflections

  • 3170 independent reflections

  • 2401 reflections with I > 2σ(I)

  • Rint = 0.039

2.3. Refinement

  • R[F2 > 2σ(F2)] = 0.043

  • wR(F2) = 0.117

  • S = 1.04

  • 3170 reflections

  • 138 parameters

  • H-atom parameters constrained

  • Δρmax = 0.31 e Å−3

  • Δρmin = −0.20 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C6—H6C⋯O1i 0.98 2.55 3.5264 (19) 178
C11—H11⋯O1ii 0.95 2.57 3.2744 (17) 132
Symmetry codes: (i) -x, -y+1, -z+1; (ii) [-x+1, y-{\script{1\over 2}}, -z+{\script{3\over 2}}].

Data collection: APEX2 (Bruker, 2005[Bruker (2005). SADABS, APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2005[Bruker (2005). SADABS, APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; 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: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

The potent antiepileptic properties of α-substituted cyclic imides have been known for over fifty years (Chen et al., 1951; Vida & Gerry, 1977). For instance, 1,3-dimethyl-3-phenylpyrrolidine-2,5-dione (methsuximide) is a broad-spectrum anticonvulsant, valuable in the treatment of medically intractable epilepsy (Sigler et al., 2001). In vivo, methsuximide is rapidly converted into its active metabolite, 3-methyl-3-phenylpyrrolidine-2,5-dione (α-methyl-α-phenylsuccinimide). Very recently we have studied the solid-state properties and crystal structures of racemic and homochiral forms of α-methyl-α-phenylsuccinimide (Khrustalev et al., 2014; Chen et al., 2014). Moreover, we have found and described the different polymorphic modifications of this compound (Khrustalev et al., 2014). In this paper we report crystal structure of 1,3-dimethyl-3-phenylpyrrolidine-2,5-dione (methsuximide, trade-mark is Celontin).

The molecule of the title compound, C12H13NO2, contains the five-membered ring in a flattened envelope conformation; the C3 carbon atom is out of the mean plane passed through the other atoms of the ring (r.m.s. deviation is 0.0038) by 0.1877 (18) Å (Fig. 1). A similar conformation of the five-membered ring was also observed in other N-substituted succinimide derivatives (Argay & Seres, 1973; Kwiatkowski & Karolak-Wojciechowska, 1992). It should be noted that the five-membered ring in the N-unsubstituted succinimide derivatives adopts almost planar conformation (Argay & Kálmán, 1973; Argay & Carstensen-Oeser, 1973; Khrustalev et al., 2014). The phenyl substituent is practically perpendicular to the five-membered ring; the dihedral angle between the planar part of the five-membered ring and the phenyl plane is 87.01 (5) °.

In the crystal, the molecules are linked by weak intermolecular C–H···O hydrogen bonds (Table 1) as well as carbonyl-carbonyl C5 O2···C5iO2i [C5···O2i and O2···C5i distances are 3.2879 (19) Å; symmetry code: (i) - x, - y, - z+1] attractive interactions (Allen et al., 1998) into a three-dimensional framework (Fig. 2).

It is important to point out that atom O2 does not form any intermolecular C–H···O hydrogen bonds due to the above-mentioned carbonyl-carbonyl interactions. Interestingly, molecular docking indicates that methsuximide seems to be incapable of forming hydrogen bonds with its protein target(s), which may explain why methsuximide, unlike 3-methyl-3-phenylpyrrolidine-2,5-dione, does not inhibit the nicotinic acetylcholine receptor (Chen et al., 2014).

Previously, the different polymorphic modifications for close analogs of the ethosuximide (Lin et al., 2012) and phensuximide (Kuhnert-Brandstätter & Bösch, 1978) derivatives were found by powder X-ray diffraction, IR spectroscopy and DSC methods. In search of polymorphic modifications for methsuximide we have carried out the DSC study of the title compound. However, no peaks that correspond to phase transitions, except for melting, were observed.

Related literature top

For general background to the properties of α-substituted cyclic imides, see: Chen et al. (1951, 2014); Vida & Gerry (1977); Kuhnert-Brandstätter & Bösch (1978); Sigler et al. (2001); Lin et al. (2012). For the crystal structures of some succinimide derivatives, see: Argay & Carstensen-Oeser (1973); Argay & Kálmán (1973); Argay & Seres (1973); Kwiatkowski & Karolak-Wojciechowska (1992); Khrustalev et al. (2014). For carbonyl–carbonyl interactions, see: Allen et al. (1998).

Experimental top

1,3-Dimethyl-3-phenylpyrrolidine-2,5-dione (methsuximide, reference standard grade) was obtained under a Material Transfer Agreement with Pfizer Inc. and used without any further purification. The single crystals of the title compound were grown by slow evaporation of an EtOH/H2O (3:1) solvent mixture at room temperature; m.p. = 328-332 K.

Refinement top

All H atoms were placed in calculated positions, with C–H = 0.95 Å (phenyl-H), 0.98 Å (methyl-H) and 0.99 Å (methylene-H) and refined as riding atoms with Uiso(H) = 1.5Ueq(C-methyl) and = 1.2Ueq(C) for other H atoms.

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); 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. Molecular structure of the title molecule, with atom labelling. Displacement ellipsoids are drawn at the 50% probability level.
[Figure 2] Fig. 2. A view along the b axis of the crystal packing of the title compound. The C–H···O hydrogen bonds (see Table 1 for details) and attractive C O···CO interactions are shown as dashed lines.
1,3-Dimethyl-3-phenylpyrrolidine-2,5-dione top
Crystal data top
C12H13NO2F(000) = 432
Mr = 203.23Dx = 1.312 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 2487 reflections
a = 10.517 (5) Åθ = 4.3–30.4°
b = 7.383 (3) ŵ = 0.09 mm1
c = 13.568 (6) ÅT = 100 K
β = 102.332 (6)°Prism, colourless
V = 1029.2 (8) Å30.45 × 0.35 × 0.25 mm
Z = 4
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer
3170 independent reflections
Radiation source: fine-focus sealed tube2401 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.039
ϕ and ω scansθmax = 30.7°, θmin = 4.3°
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
h = 1415
Tmin = 0.961, Tmax = 0.978k = 1010
11948 measured reflectionsl = 1919
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)] = 0.043Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.117H-atom parameters constrained
S = 1.04 w = 1/[σ2(Fo2) + (0.051P)2 + 0.2557P]
where P = (Fo2 + 2Fc2)/3
3170 reflections(Δ/σ)max < 0.001
138 parametersΔρmax = 0.31 e Å3
0 restraintsΔρmin = 0.20 e Å3
Crystal data top
C12H13NO2V = 1029.2 (8) Å3
Mr = 203.23Z = 4
Monoclinic, P21/cMo Kα radiation
a = 10.517 (5) ŵ = 0.09 mm1
b = 7.383 (3) ÅT = 100 K
c = 13.568 (6) Å0.45 × 0.35 × 0.25 mm
β = 102.332 (6)°
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer
3170 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
2401 reflections with I > 2σ(I)
Tmin = 0.961, Tmax = 0.978Rint = 0.039
11948 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0430 restraints
wR(F2) = 0.117H-atom parameters constrained
S = 1.04Δρmax = 0.31 e Å3
3170 reflectionsΔρmin = 0.20 e Å3
138 parameters
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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
O10.22108 (8)0.49025 (12)0.54547 (6)0.0254 (2)
O20.05261 (9)0.03777 (14)0.63342 (7)0.0329 (2)
N10.12281 (9)0.24733 (15)0.60341 (7)0.0230 (2)
C20.21177 (11)0.32854 (16)0.55604 (8)0.0197 (2)
C30.29566 (11)0.18081 (15)0.52209 (8)0.0178 (2)
C40.22286 (11)0.00564 (16)0.53825 (9)0.0213 (2)
H4A0.17970.04760.47260.026*
H4B0.28400.08460.57610.026*
C50.12347 (11)0.06034 (18)0.59769 (8)0.0232 (2)
C60.03228 (12)0.3509 (2)0.64901 (10)0.0320 (3)
H6A0.07820.45300.68700.048*
H6B0.00350.27260.69480.048*
H6C0.03870.39670.59600.048*
C70.43011 (10)0.19242 (14)0.59288 (8)0.0165 (2)
C80.53672 (11)0.26871 (15)0.56295 (9)0.0207 (2)
H80.52730.31410.49630.025*
C90.65706 (11)0.27933 (16)0.62961 (10)0.0236 (3)
H90.72880.33230.60810.028*
C100.67313 (12)0.21356 (16)0.72690 (10)0.0233 (2)
H100.75580.21940.77180.028*
C110.56728 (11)0.13896 (16)0.75822 (9)0.0214 (2)
H110.57720.09400.82500.026*
C120.44715 (11)0.12992 (15)0.69216 (8)0.0186 (2)
H120.37500.08030.71470.022*
C130.29842 (13)0.21253 (17)0.41107 (9)0.0240 (3)
H13A0.33020.33520.40270.036*
H13B0.21040.19880.36970.036*
H13C0.35640.12390.38970.036*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0279 (5)0.0234 (4)0.0231 (4)0.0064 (3)0.0012 (3)0.0014 (3)
O20.0212 (4)0.0458 (6)0.0329 (5)0.0032 (4)0.0084 (4)0.0098 (4)
N10.0173 (5)0.0324 (6)0.0196 (5)0.0046 (4)0.0046 (4)0.0000 (4)
C20.0172 (5)0.0258 (6)0.0147 (5)0.0035 (4)0.0002 (4)0.0000 (4)
C30.0188 (5)0.0192 (5)0.0159 (5)0.0011 (4)0.0047 (4)0.0008 (4)
C40.0189 (5)0.0236 (6)0.0214 (5)0.0023 (4)0.0041 (4)0.0010 (4)
C50.0160 (5)0.0340 (6)0.0186 (5)0.0003 (4)0.0016 (4)0.0034 (5)
C60.0210 (6)0.0474 (8)0.0292 (6)0.0099 (5)0.0086 (5)0.0032 (6)
C70.0173 (5)0.0153 (5)0.0179 (5)0.0017 (4)0.0058 (4)0.0001 (4)
C80.0221 (6)0.0193 (5)0.0232 (5)0.0014 (4)0.0102 (4)0.0031 (4)
C90.0186 (5)0.0186 (5)0.0358 (7)0.0012 (4)0.0113 (5)0.0025 (5)
C100.0193 (5)0.0196 (5)0.0295 (6)0.0026 (4)0.0023 (4)0.0066 (4)
C110.0232 (6)0.0215 (5)0.0189 (5)0.0034 (4)0.0033 (4)0.0015 (4)
C120.0190 (5)0.0183 (5)0.0195 (5)0.0002 (4)0.0061 (4)0.0000 (4)
C130.0316 (6)0.0249 (6)0.0158 (5)0.0015 (5)0.0061 (5)0.0000 (4)
Geometric parameters (Å, º) top
O1—C21.2089 (15)C7—C81.3907 (16)
O2—C51.2122 (15)C7—C121.3987 (16)
N1—C21.3802 (15)C8—C91.3918 (18)
N1—C51.3828 (18)C8—H80.9500
N1—C61.4580 (16)C9—C101.3826 (19)
C2—C31.5342 (16)C9—H90.9500
C3—C131.5308 (17)C10—C111.3876 (17)
C3—C71.5328 (16)C10—H100.9500
C3—C41.5422 (16)C11—C121.3859 (16)
C4—C51.5055 (17)C11—H110.9500
C4—H4A0.9900C12—H120.9500
C4—H4B0.9900C13—H13A0.9800
C6—H6A0.9800C13—H13B0.9800
C6—H6B0.9800C13—H13C0.9800
C6—H6C0.9800
C2—N1—C5113.30 (10)H6B—C6—H6C109.5
C2—N1—C6122.61 (11)C8—C7—C12118.00 (10)
C5—N1—C6123.98 (11)C8—C7—C3122.21 (10)
O1—C2—N1124.36 (11)C12—C7—C3119.76 (10)
O1—C2—C3126.88 (11)C7—C8—C9120.73 (11)
N1—C2—C3108.76 (10)C7—C8—H8119.6
C13—C3—C7113.53 (9)C9—C8—H8119.6
C13—C3—C2108.64 (9)C10—C9—C8120.63 (11)
C7—C3—C2106.55 (9)C10—C9—H9119.7
C13—C3—C4112.49 (9)C8—C9—H9119.7
C7—C3—C4112.17 (9)C9—C10—C11119.29 (11)
C2—C3—C4102.63 (9)C9—C10—H10120.4
C5—C4—C3105.90 (10)C11—C10—H10120.4
C5—C4—H4A110.6C12—C11—C10120.09 (11)
C3—C4—H4A110.6C12—C11—H11120.0
C5—C4—H4B110.6C10—C11—H11120.0
C3—C4—H4B110.6C11—C12—C7121.24 (10)
H4A—C4—H4B108.7C11—C12—H12119.4
O2—C5—N1124.28 (12)C7—C12—H12119.4
O2—C5—C4127.63 (12)C3—C13—H13A109.5
N1—C5—C4108.07 (10)C3—C13—H13B109.5
N1—C6—H6A109.5H13A—C13—H13B109.5
N1—C6—H6B109.5C3—C13—H13C109.5
H6A—C6—H6B109.5H13A—C13—H13C109.5
N1—C6—H6C109.5H13B—C13—H13C109.5
H6A—C6—H6C109.5
C5—N1—C2—O1174.37 (10)C3—C4—C5—O2173.64 (11)
C6—N1—C2—O12.00 (17)C3—C4—C5—N17.94 (12)
C5—N1—C2—C36.64 (13)C13—C3—C7—C815.33 (15)
C6—N1—C2—C3176.99 (10)C2—C3—C7—C8104.22 (12)
O1—C2—C3—C1350.84 (15)C4—C3—C7—C8144.23 (10)
N1—C2—C3—C13130.20 (10)C13—C3—C7—C12166.67 (10)
O1—C2—C3—C771.83 (14)C2—C3—C7—C1273.78 (12)
N1—C2—C3—C7107.13 (10)C4—C3—C7—C1237.77 (13)
O1—C2—C3—C4170.14 (11)C12—C7—C8—C91.08 (16)
N1—C2—C3—C410.91 (11)C3—C7—C8—C9179.11 (10)
C13—C3—C4—C5127.64 (10)C7—C8—C9—C100.25 (17)
C7—C3—C4—C5102.92 (10)C8—C9—C10—C110.98 (17)
C2—C3—C4—C511.07 (11)C9—C10—C11—C120.36 (17)
C2—N1—C5—O2179.41 (11)C10—C11—C12—C71.00 (17)
C6—N1—C5—O23.10 (18)C8—C7—C12—C111.70 (16)
C2—N1—C5—C40.93 (13)C3—C7—C12—C11179.79 (10)
C6—N1—C5—C4175.39 (10)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C6—H6C···O1i0.982.553.5264 (19)178
C11—H11···O1ii0.952.573.2744 (17)132
Symmetry codes: (i) x, y+1, z+1; (ii) x+1, y1/2, z+3/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C6—H6C···O1i0.982.553.5264 (19)178
C11—H11···O1ii0.952.573.2744 (17)132
Symmetry codes: (i) x, y+1, z+1; (ii) x+1, y1/2, z+3/2.
 

Acknowledgements

Funding from the US National Science Foundation (PREM DMR-0934212 and IIA-1301346) and the 2013–2020 Program aimed at maximizing the ITMO University's competitive advantage among the world's leading education centers 5/100 is gratefully acknowledged. We thank Dr Arcadius V. Krivoshein (Albany College of Pharmacy & Health Sciences, Albany, New York) for providing us with methsuximide and help in obtaining the single crystals for this investigation.

References

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Volume 70| Part 9| September 2014| Pages o942-o943
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