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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 67| Part 1| January 2011| Page o208
https://doi.org/10.1107/S1600536810052396

Naphthalene-2,6-dicarb­­oxy­lic acid–1-methyl­pyrrolidin-2-one (1/2)

Bianhua Wu,a Ge Peng,b Youwei Cheng,a* Xi Lia and Jiyong Liuc

aDepartment of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, People's Republic of China, bChemical Engineering College, Ningbo University of Technology, Ningbo 315016, People's Republic of China, and cDepartment of Chemistry, Zhejiang University, Hangzhou 310027, People's Republic of China
*Correspondence e-mail: ywcheng@zju.edu.cn

(Received 2 December 2010; accepted 14 December 2010; online 24 December 2010)

The asymmetric unit of the title compound, C12H8O4·2C5H9NO, contains one half-mol­ecule of naphthalene-2,6-dicarb­oxy­lic acid (NDA) and one mol­ecule of 1-methyl­pyrrolidin-2-one (NMP): the NDA molecules lie on the crystallographic twofold rotation axes. In the crystal, the components are linked by strong O—H⋯O hydrogen bonds and C—H⋯O inter­actions.

Related literature

For the crystal structure of naphthalene-2,6-dicarb­oxy­lic acid (NDA), see: Kaduk & Golab (1999[Kaduk, J. A. & Golab, J. T. (1999). Acta Cryst. B55, 85-94.]). For the crystal structure of N-methyl-2-Pyrrolidone (NMP), see: Müller et al. (1996[Müller, G., Lutz, M. & Harder, S. (1996). Acta Cryst. B52, 1014-1022.]). For the purification of NDA, see: Nagase et al. (2004[Nagase, Y., Yamamoto, K., Tanaka, T. & Hamaguchi, M. (2004). US Patent No. 6756509.]). For related structures, see: Guo et al. (2009[Guo, X., Cheng, Y. & Li, X. (2009). Acta Cryst. E65, o1794.]); Dale & Elsegood (2004[Dale, S. H. & Elsegood, M. R. J. (2004). Acta Cryst. C60, o444-o448.]).

[Scheme 1]

Experimental

Crystal data

  • C12H8O4·2C5H9NO

  • Mr = 414.45

  • Orthorhombic, F d d 2

  • a = 19.7306 (11) Å

  • b = 28.7632 (19) Å

  • c = 7.1906 (4) Å

  • V = 4080.8 (4) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 0.10 mm−1

  • T = 120 K

  • 0.30 × 0.11 × 0.10 mm
Data collection

  • Oxford Diffraction Xcalibur Atlas Gemini ultra diffractometer

  • Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2009[Oxford Diffraction (2009). CrysAlis PRO. Oxford Diffraction Ltd, Yarnton, England.]) Tmin = 0.987, Tmax = 0.990

  • 3255 measured reflections

  • 1017 independent reflections

  • 847 reflections with I > 2σ(I)

  • Rint = 0.037
Refinement

  • R[F2 > 2σ(F2)] = 0.037

  • wR(F2) = 0.087

  • S = 1.05

  • 1017 reflections

  • 138 parameters

  • 1 restraint

  • H-atom parameters constrained

  • Δρmax = 0.17 e Å−3

  • Δρmin = −0.20 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
O1—H1⋯O3 0.82 1.75 2.556 (3) 165
C2—H2⋯O2i 0.93 2.48 3.163 (4) 131
C8—H8A⋯O2 0.97 2.47 3.311 (4) 145
Symmetry code: (i) [x+{\script{1\over 4}}, -y+{\script{1\over 4}}, z+{\script{1\over 4}}].

Data collection: CrysAlis PRO (Oxford Diffraction, 2009[Oxford Diffraction (2009). CrysAlis PRO. Oxford Diffraction Ltd, 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, 12008); molecular graphics: OLEX2 (Dolomanov et al., 2009[Dolomanov, O. V., Bourhis, L. J., Gildea, R. J., Howard, J. A. K. & Puschmann, H. (2009). J. Appl. Cryst. 42, 339-341.]); software used to prepare material for publication: OLEX2.

Supporting information

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S1600536810052396/su2234sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810052396/su2234Isup2.hkl

checkCIF report


Comment top

Naphthalene-2,6-dicarboxylic acid (NDA) is an important monomer for producing polyester and polyurethane materials and liquid crystal polymers (LCP). During the manufacturing process, the impurities in NDA, such as 6-formyl-2-naphthoic acid (FNA), debase the quality of the products dramatically. So the purification of NDA is very important however, this process is difficult (Nagase et al., 2004). Although many methods have been proposed in this field, they are either too complex or not cost effective. Recently, we have obtained crystals of the title compound, a mixture of NDA and N-Methyl Pyrrolidone (NMP). We call this phenomenon adductive crystallization and intend to apply this crystallization technique to the purification of NDA.

NDA crystallizes in the triclinic space group P1 (Kaduk & Golab, 1999), while NMP crystlalizes in the monoclinc space group P21/c (Müller et al., 1996). There have also been some reports on the adductive crystallization of dicarboxylic acids and amides, such as Terephthalic acid (TA) and N,N-dimethylacetamide (Guo et al., 2009) and TA and N,N-dimethylformamide (Dale & Elsegood, 2004).

The title compound crystallized in the orthorhombic space group Fdd2, and the molecular structure is shown in Fig. 1. The asymmetric unit contains one half-molecule of NDA and one molecule of NMP. The pyrrolidone group has an envelope conformation with atom C9 at the flap. The dihedral angle between the mean planes of the naphthalene ring of the NDA molecule and the pyrrolidone ring of the NMP molecule is 22.39 (15)°.

In the crystal the NDA and NMP molecules are linked by strong O—H···O hydrogen bonds and C-H···O interactions (Fig. 2 and Table 1).

Related literature top

For the crystal structure of naphthalene-2,6-dicarboxylic acid (NDA), see: Kaduk & Golab (1999). For the crystal structure of N-methyl-2-Pyrrolidone (NMP), see: Müller et al. (1996). For the purification of NDA, see: Nagase et al. (2004). For related structures, see: Guo et al. (2009); Dale & Elsegood (2004).

Experimental top

The title compound was obtained by putting 0.1 g of Naphthalene-2,6-dicarboxylic acid (NDA) into 1 ml of N-Methyl Pyrrolidone (NMP) at room temperature and then leaving the mixture in the freezer, which was maintained at 255 K, for 72 h. During the process, we observed the gradual disappearance of the NDA powder and the appearance of colourless needle-like crystals of the title compound.

Refinement top

In the final cycles of refinement, in the absence of significant anomalous scattering effects, Friedel pairs were merged and Δf " set to zero. The H-atoms were placed in calculated positions and were refined using a riding model: O—H = 0.82 Å, C—Haromatic = 0.93 Å, C—Halkyl = 0.97 Å, C—Hmethyl = 0.96 Å, with Uiso(H) = k × Ueq(O or C), where k = 1.5 for CH3 H-atoms and k = 1.2 for all other H-atoms.

Structure description top

Naphthalene-2,6-dicarboxylic acid (NDA) is an important monomer for producing polyester and polyurethane materials and liquid crystal polymers (LCP). During the manufacturing process, the impurities in NDA, such as 6-formyl-2-naphthoic acid (FNA), debase the quality of the products dramatically. So the purification of NDA is very important however, this process is difficult (Nagase et al., 2004). Although many methods have been proposed in this field, they are either too complex or not cost effective. Recently, we have obtained crystals of the title compound, a mixture of NDA and N-Methyl Pyrrolidone (NMP). We call this phenomenon adductive crystallization and intend to apply this crystallization technique to the purification of NDA.

NDA crystallizes in the triclinic space group P1 (Kaduk & Golab, 1999), while NMP crystlalizes in the monoclinc space group P21/c (Müller et al., 1996). There have also been some reports on the adductive crystallization of dicarboxylic acids and amides, such as Terephthalic acid (TA) and N,N-dimethylacetamide (Guo et al., 2009) and TA and N,N-dimethylformamide (Dale & Elsegood, 2004).

The title compound crystallized in the orthorhombic space group Fdd2, and the molecular structure is shown in Fig. 1. The asymmetric unit contains one half-molecule of NDA and one molecule of NMP. The pyrrolidone group has an envelope conformation with atom C9 at the flap. The dihedral angle between the mean planes of the naphthalene ring of the NDA molecule and the pyrrolidone ring of the NMP molecule is 22.39 (15)°.

In the crystal the NDA and NMP molecules are linked by strong O—H···O hydrogen bonds and C-H···O interactions (Fig. 2 and Table 1).

For the crystal structure of naphthalene-2,6-dicarboxylic acid (NDA), see: Kaduk & Golab (1999). For the crystal structure of N-methyl-2-Pyrrolidone (NMP), see: Müller et al. (1996). For the purification of NDA, see: Nagase et al. (2004). For related structures, see: Guo et al. (2009); Dale & Elsegood (2004).

Computing details top

Data collection: CrysAlis PRO (Oxford Diffraction, 2009); cell refinement: CrysAlis PRO (Oxford Diffraction, 2009); data reduction: CrysAlis PRO (Oxford Diffraction, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 12008); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the Naphthalene-2,6-dicarboxylic acid molecule and one N-Methyl-2-Pyrrolidone molecule of the title compound. Displacement ellipsoids are drawn at the 50% probability level [Symmetry code: A = -x + 0.5, -y + 0.5, z].
[Figure 2] Fig. 2. The crystal packing viewed along the c-axis of the title compound, showing the intermolecular O-H···O hydrogen bonds and C-H···O interactions as dashed lines [see Table 1 for details].
Naphthalene-2,6-dicarboxylic acid–1-methylpyrrolidin-2-one (1/2) top
Crystal data top
C12H8O4·2C5H9NOF(000) = 1760
Mr = 414.45Dx = 1.349 Mg m−3
Orthorhombic, Fdd2Mo Kα radiation, λ = 0.71073 Å
Hall symbol: F 2 -2dCell parameters from 1127 reflections
a = 19.7306 (11) Åθ = 3.1–29.2°
b = 28.7632 (19) ŵ = 0.10 mm−1
c = 7.1906 (4) ÅT = 120 K
V = 4080.8 (4) Å3Needle, colourless
Z = 80.30 × 0.11 × 0.10 mm
Data collection top
Oxford Diffraction Xcalibur Atlas Gemini ultra
diffractometer		1017 independent reflections
Radiation source: fine-focus sealed tube847 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.037
Detector resolution: 10.3592 pixels mm-1θmax = 25.4°, θmin = 3.1°
ω scansh = −23→19
Absorption correction: multi-scan
(CrysAlis PRO; Oxford Diffraction, 2009)		k = −22→34
Tmin = 0.987, Tmax = 0.990l = −8→7
3255 measured reflections
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)] = 0.037Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.087H-atom parameters constrained
S = 1.05 w = 1/[σ2(Fo2) + (0.0405P)2 + 1.8717P]
where P = (Fo2 + 2Fc2)/3
1017 reflections(Δ/σ)max < 0.001
138 parametersΔρmax = 0.17 e Å−3
1 restraintΔρmin = −0.20 e Å−3
Crystal data top
C12H8O4·2C5H9NOV = 4080.8 (4) Å3
Mr = 414.45Z = 8
Orthorhombic, Fdd2Mo Kα radiation
a = 19.7306 (11) ŵ = 0.10 mm−1
b = 28.7632 (19) ÅT = 120 K
c = 7.1906 (4) Å0.30 × 0.11 × 0.10 mm
Data collection top
Oxford Diffraction Xcalibur Atlas Gemini ultra
diffractometer		1017 independent reflections
Absorption correction: multi-scan
(CrysAlis PRO; Oxford Diffraction, 2009)		847 reflections with I > 2σ(I)
Tmin = 0.987, Tmax = 0.990Rint = 0.037
3255 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0371 restraint
wR(F2) = 0.087H-atom parameters constrained
S = 1.05Δρmax = 0.17 e Å−3
1017 reflectionsΔρmin = −0.20 e Å−3
138 parameters
Special details top

Experimental. Empirical absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm; CrysAlis PRO (Oxford Diffraction, 2009).

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell esds are taken into account in the estimation of distances, angles and torsion angles

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
O10.24703 (10)0.09264 (7)0.7871 (3)0.0278 (7)
O20.13547 (10)0.10088 (8)0.7582 (4)0.0385 (8)
C10.27857 (13)0.23501 (10)0.7441 (4)0.0168 (8)
C20.26776 (13)0.18651 (10)0.7497 (4)0.0180 (8)
C30.20359 (13)0.16856 (10)0.7495 (4)0.0177 (8)
C40.14695 (13)0.19829 (10)0.7411 (4)0.0200 (9)
C50.15563 (13)0.24549 (10)0.7410 (4)0.0191 (9)
C60.19144 (14)0.11756 (10)0.7638 (4)0.0200 (8)
O30.23717 (10)0.00444 (7)0.8202 (3)0.0252 (7)
N10.18459 (12)−0.06402 (9)0.8830 (4)0.0223 (7)
C70.18914 (15)−0.01786 (11)0.8877 (4)0.0219 (9)
C80.12795 (15)0.00109 (11)0.9868 (5)0.0252 (9)
C90.07849 (14)−0.03970 (11)0.9918 (5)0.0259 (10)
C100.12448 (14)−0.08267 (11)0.9734 (5)0.0256 (10)
C110.23599 (16)−0.09402 (11)0.8060 (5)0.0294 (10)
H10.236800.065200.800000.0420*
H20.304800.166500.753700.0220*
H40.103500.185800.735700.0240*
H50.118000.264900.738900.0230*
H8A0.108800.027200.919400.0300*
H8B0.139500.011101.111600.0300*
H9A0.04650−0.038000.889500.0310*
H9B0.05360−0.040301.108100.0310*
H10A0.10330−0.106500.897600.0310*
H10B0.13540−0.095601.094300.0310*
H11A0.21610−0.113800.713500.0440*
H11B0.27090−0.075500.750000.0440*
H11C0.25520−0.112700.903200.0440*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0248 (11)0.0165 (11)0.0421 (14)−0.0012 (9)0.0016 (10)0.0040 (11)
O20.0264 (12)0.0216 (12)0.0675 (17)−0.0061 (10)−0.0131 (13)0.0029 (13)
C10.0178 (13)0.0197 (15)0.0130 (13)−0.0010 (12)0.0015 (13)0.0011 (14)
C20.0217 (14)0.0186 (15)0.0138 (14)0.0029 (12)0.0002 (13)−0.0012 (14)
C30.0199 (15)0.0193 (15)0.0138 (14)−0.0001 (13)−0.0024 (12)−0.0009 (14)
C40.0165 (14)0.0266 (18)0.0170 (14)−0.0037 (13)−0.0015 (14)0.0019 (14)
C50.0178 (14)0.0213 (17)0.0183 (14)0.0027 (12)−0.0011 (13)0.0007 (14)
C60.0214 (14)0.0187 (15)0.0200 (15)−0.0002 (14)−0.0025 (13)0.0012 (14)
O30.0240 (12)0.0195 (11)0.0322 (13)−0.0027 (10)0.0047 (10)0.0025 (11)
N10.0213 (12)0.0209 (13)0.0247 (13)0.0002 (12)0.0021 (11)0.0037 (12)
C70.0235 (15)0.0213 (16)0.0209 (15)0.0002 (15)−0.0058 (13)0.0006 (14)
C80.0256 (15)0.0263 (17)0.0238 (16)0.0049 (14)0.0001 (13)−0.0018 (17)
C90.0229 (15)0.0301 (19)0.0246 (16)0.0012 (14)0.0011 (15)0.0034 (16)
C100.0250 (16)0.0281 (18)0.0237 (17)−0.0052 (15)0.0004 (13)0.0065 (15)
C110.0313 (18)0.0259 (18)0.0309 (17)0.0064 (15)0.0019 (15)0.0017 (16)
Geometric parameters (Å, º) top
O1—C61.321 (3)C4—H40.9300
O2—C61.205 (3)C5—H50.9300
O1—H10.8200C7—C81.504 (4)
O3—C71.243 (4)C8—C91.527 (4)
N1—C71.331 (4)C9—C101.539 (4)
N1—C101.455 (4)C8—H8A0.9700
N1—C111.442 (4)C8—H8B0.9700
C1—C5i1.414 (4)C9—H9A0.9700
C1—C1i1.419 (4)C9—H9B0.9700
C1—C21.412 (4)C10—H10A0.9700
C2—C31.367 (4)C10—H10B0.9700
C3—C61.490 (4)C11—H11A0.9600
C3—C41.409 (4)C11—H11B0.9600
C4—C51.368 (4)C11—H11C0.9600
C2—H20.9300
C6—O1—H1109.00C7—C8—C9104.2 (3)
C10—N1—C11121.6 (3)C8—C9—C10103.8 (2)
C7—N1—C10114.3 (2)N1—C10—C9102.9 (2)
C7—N1—C11124.0 (3)C7—C8—H8A111.00
C2—C1—C5i122.1 (2)C7—C8—H8B111.00
C1i—C1—C5i119.2 (3)C9—C8—H8A111.00
C1i—C1—C2118.7 (2)C9—C8—H8B111.00
C1—C2—C3120.9 (2)H8A—C8—H8B109.00
C4—C3—C6118.2 (2)C8—C9—H9A111.00
C2—C3—C6121.4 (2)C8—C9—H9B111.00
C2—C3—C4120.4 (3)C10—C9—H9A111.00
C3—C4—C5120.2 (2)C10—C9—H9B111.00
C1i—C5—C4120.6 (2)H9A—C9—H9B109.00
O1—C6—O2123.3 (3)N1—C10—H10A111.00
O2—C6—C3122.5 (3)N1—C10—H10B111.00
O1—C6—C3114.2 (2)C9—C10—H10A111.00
C3—C2—H2120.00C9—C10—H10B111.00
C1—C2—H2120.00H10A—C10—H10B109.00
C3—C4—H4120.00N1—C11—H11A109.00
C5—C4—H4120.00N1—C11—H11B110.00
C4—C5—H5120.00N1—C11—H11C109.00
C1i—C5—H5120.00H11A—C11—H11B109.00
O3—C7—N1123.8 (3)H11A—C11—H11C110.00
O3—C7—C8127.6 (3)H11B—C11—H11C109.00
N1—C7—C8108.6 (3)
C10—N1—C7—O3179.0 (3)C1—C2—C3—C40.9 (4)
C10—N1—C7—C8−0.7 (4)C2—C3—C6—O13.7 (4)
C11—N1—C7—O32.7 (5)C2—C3—C4—C5−2.8 (4)
C11—N1—C7—C8−177.1 (3)C6—C3—C4—C5175.4 (3)
C7—N1—C10—C915.8 (4)C4—C3—C6—O24.1 (4)
C11—N1—C10—C9−167.8 (3)C2—C3—C6—O2−177.7 (3)
C2—C1—C5i—C4i−178.1 (3)C4—C3—C6—O1−174.5 (3)
C2—C1—C1i—C5−2.9 (4)C3—C4—C5—C1i1.8 (4)
C1i—C1—C2—C31.9 (4)O3—C7—C8—C9165.4 (3)
C5i—C1—C2—C3−178.9 (3)N1—C7—C8—C9−14.9 (3)
C2—C1—C1i—C2i176.3 (3)C7—C8—C9—C1023.5 (3)
C5i—C1—C1i—C5177.9 (3)C8—C9—C10—N1−23.5 (3)
C1—C2—C3—C6−177.3 (3)
Symmetry code: (i) −x+1/2, −y+1/2, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···O30.821.752.556 (3)165
C2—H2···O2ii0.932.483.163 (4)131
C8—H8A···O20.972.473.311 (4)145
Symmetry code: (ii) x+1/4, −y+1/4, z+1/4.

Experimental details

Crystal data
Chemical formulaC12H8O4·2C5H9NO
Mr414.45
Crystal system, space groupOrthorhombic, Fdd2
Temperature (K)120
a, b, c (Å)19.7306 (11), 28.7632 (19), 7.1906 (4)
V (Å3)4080.8 (4)
Z8
Radiation typeMo Kα
µ (mm−1)0.10
Crystal size (mm)0.30 × 0.11 × 0.10
Data collection
DiffractometerOxford Diffraction Xcalibur Atlas Gemini ultra
Absorption correctionMulti-scan
(CrysAlis PRO; Oxford Diffraction, 2009)
Tmin, Tmax0.987, 0.990
No. of measured, independent and
observed [I > 2σ(I)] reflections		3255, 1017, 847
Rint0.037
(sin θ/λ)max (Å−1)0.602
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.037, 0.087, 1.05
No. of reflections1017
No. of parameters138
No. of restraints1
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.17, −0.20

Computer programs: CrysAlis PRO (Oxford Diffraction, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 12008), OLEX2 (Dolomanov et al., 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···O30.821.752.556 (3)165
C2—H2···O2i0.932.483.163 (4)131
C8—H8A···O20.972.473.311 (4)145
Symmetry code: (i) x+1/4, −y+1/4, z+1/4.
 

References

First citationDale, S. H. & Elsegood, M. R. J. (2004). Acta Cryst. C60, o444–o448.  Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
 First citationDolomanov, O. V., Bourhis, L. J., Gildea, R. J., Howard, J. A. K. & Puschmann, H. (2009). J. Appl. Cryst. 42, 339–341.  Web of Science CrossRef CAS IUCr Journals Google Scholar
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ISSN: 2056-9890
Volume 67| Part 1| January 2011| Page o208
https://doi.org/10.1107/S1600536810052396
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