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

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ISSN: 2056-9890

10,11-Di­hydro­carbamazepine–acetic acid (1/1)

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aSolid-State Research Group, Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, 27 Taylor Street, Glasgow G4 0NR, Scotland, and bWestCHEM, Department of Pure and Applied Chemistry, University of Strathclyde, 295 Cathedral Street, Glasgow G1 1XL, Scotland
*Correspondence e-mail: alastair.florence@strath.ac.uk

(Received 12 October 2006; accepted 24 October 2006; online 3 November 2006)

In the title compound [systematic name: 10,11-dihydro-5H-dibenz[b,f]azepine-5-carboxamide–ethanoic acid (1/1)], C15H14N2O·C2H4O2, the dihydro­carbamazepine and acetic acid mol­ecules are hydrogen bonded to form an R22(8) motif, which is further connected into a centrosymmetric double motif arrangement.

Comment

10,11-Dihydro­carbamazepine (DHC) is a recognized impurity in carbamazepine (CBZ), a dibenzazepine drug used to control seizures (Cyr et al., 1987[Cyr, T. D., Matsui, F., Sears, R. W., Curran, N. M. & Lovering, E. G. (1987). J. Assoc. Off. Anal. Chem. 70, 836-840.]). DHC is known to crystallize in three polymorphic forms: monoclinic form I (Bandoli et al., 1992[Bandoli, G., Nicolini, M., Ongaro, A., Volpe, G. & Rubello, A. (1992). J. Chem. Crystallogr. 22, 177-183.]), ortho­rhom­bic form II (Harrison et al., 2006[Harrison, W. T. A., Yathirajan, H. S. & Anilkumar, H. G. (2006). Acta Cryst. C62, o240-o242.]) and triclinic form III (Leech et al., 2006[Leech, C. K., Florence, A. J., Shankland, K., Shankland, N. & Johnston, A. (2006). Acta Cryst. E62. Submitted.]). The title compound, (I)[link], was produced during an automated parallel crystallization study (Florence, Johnston, Fernandes et al., 2006[Florence, A. J., Johnston, A., Fernandes, P., Shankland, N. & Shankland, K. (2006). J. Appl. Cryst. In the press.]) of DHC as part of a wider study into the predicted and experimental structures of CBZ (Florence, Johnston, Price et al., 2006[Florence, A. J., Johnston, A., Price, S. L., Nowell, H., Shankland, N. & Kennedy, A. R. (2006). J. Pharm. Sci. 95, 1918-1930.]; Florence, Leech et al., 2006[Florence, A. J., Leech, C. K., Shankland, N., Shankland, K. & Johnston, A. (2006). CrystEngComm, 8, 746-747.]). The sample was identified as a new form using multi-sample foil transmission X-ray powder diffraction analysis (Florence et al., 2003[Florence, A. J., Baumgartner, B., Weston, C., Shankland, N., Kennedy, A. R., Shankland, K. & David, W. I. F. (2003). J. Pharm. Sci. 92, 1930-1938.]). Subsequent manual recrystallization from a saturated acetic acid solution by slow evaporation at 298 K yielded single crystals of (I)[link] suitable for X-ray diffraction.

[Scheme 1]

The crystal structure of (I)[link] is essentially isostructural with that of CBZ–acetic acid (1/1) (Fleischman et al., 2003[Fleischman, S. G., Kuduva, S. S., McMahon, J. A., Moulton, B., Walsh, R. D. B., Rodriguez-Hornedo, N. & Zaworotko, M. J. (2003). Cryst. Growth Des. 3, 909-919.]). Accordingly, it displays the same space group with very similar unit-cell parameters and packing arrangements. Specifically, the DHC and acetic acid mol­ecules are connected via O2—H1⋯O1 and N2—H2N⋯O3 hydrogen bonds (Table 1[link]) to form an R22(8) (Etter, 1990[Etter, M. C. (1990). Acc. Chem. Res. 23, 120-126.]) dimer motif (Fig. 1[link]). A third hydrogen bond, N2—H1N⋯O3i [symmetry code (i) 1 − x, 1 − y, −z], joins adjacent dimers to form a centrosymmetric double motif arrangement (Fig. 2[link]).

[Figure 1]
Figure 1
The asymmetric unit of (I)[link], showing 50% probability displacement ellipsoids. Hydrogen bonds are shown as dashed lines.
[Figure 2]
Figure 2
The hydrogen bonded R22(8) motifs of (I)[link] joined in a centrosymmetric arrangement via an R42(8) motif. Hydrogen bonds are shown as dashed lines. [Symmetry code: (b) 1 − x, 1 − y, −z.]

Experimental

Crystals of (I)[link] were grown from a saturated acetic acid solution of 10,11-dihydro­carbamazepine by isothermal solvent evaporation at 298 K.

Crystal data
  • C15H14N2O·C2H4O2

  • Mr = 298.33

  • Monoclinic, P 21 /c

  • a = 5.3104 (4) Å

  • b = 15.4246 (17) Å

  • c = 18.732 (2) Å

  • β = 95.106 (7)°

  • V = 1528.3 (3) Å3

  • Z = 4

  • Dx = 1.297 Mg m−3

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 123 (2) K

  • Needle, colourless

  • 0.35 × 0.08 × 0.04 mm

Data collection
  • Nonius KappaCCD area-detector diffractometer

  • φ and ω scans

  • Absorption correction: none

  • 10078 measured reflections

  • 2652 independent reflections

  • 1605 reflections with I > 2σ(I)

  • Rint = 0.103

  • θmax = 25.0°

Refinement
  • Refinement on F2

  • R[F2 > 2σ(F2)] = 0.076

  • wR(F2) = 0.147

  • S = 1.13

  • 2652 reflections

  • 212 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • w = 1/[σ2(Fo2) + (0.0421P)2 + 0.9028P] where P = (Fo2 + 2Fc2)/3

  • (Δ/σ)max < 0.001

  • Δρmax = 0.20 e Å−3

  • Δρmin = −0.21 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O2—H1⋯O1 1.03 (4) 1.53 (4) 2.547 (3) 167 (4)
N2—H1N⋯O3i 0.88 (4) 2.20 (3) 2.894 (4) 136 (3)
N2—H2N⋯O3 0.95 (4) 2.04 (4) 2.970 (4) 164 (4)
Symmetry code: (i) -x+1, -y+1, -z.

H atoms bonded to N and O were located in difference maps and refined isotropically (distances are given in Table 1). All other H atoms were positioned geometrically and treated as riding with C—H = 0.95–0.99 Å, and with Uiso(H) = 1.2Ueq(C), or Uiso(H) = 1.5Ueq(C) for the methyl group.

Data collection: COLLECT (Hooft, 1988[Hooft, R. (1988). COLLECT. Nonius BV, Delft, The Netherlands.]) and DENZO (Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp 307-326. New York: Academic Press.]); cell refinement: DENZO and COLLECT; data reduction: DENZO; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997[Sheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of Göttingen, Germany.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997[Sheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of Göttingen, Germany.]); molecular graphics: PLATON (Spek, 2003[Spek, A. L. (2003). J. Appl. Cryst. 36, 7-13.]); software used to prepare material for publication: SHELXL97.

Supporting information


Computing details top

Data collection: COLLECT (Hooft, 1988) and DENZO (Otwinowski & Minor, 1997); cell refinement: DENZO and COLLECT; data reduction: DENZO; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: SHELXL97.

10,11-dihydro-5H- dibenz[b,f]azepine-5-carboxamide–ethanoic acid (1/1) top
Crystal data top
C15H14N2O·C2H4O2F(000) = 632
Mr = 298.33Dx = 1.297 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
a = 5.3104 (4) ÅCell parameters from 2544 reflections
b = 15.4246 (17) Åθ = 1.0–25.0°
c = 18.732 (2) ŵ = 0.09 mm1
β = 95.106 (7)°T = 123 K
V = 1528.3 (3) Å3Needle, colourless
Z = 40.35 × 0.08 × 0.04 mm
Data collection top
Nonius KappaCCD area-detector
diffractometer
1605 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.103
Graphite monochromatorθmax = 25.0°, θmin = 3.4°
φ and ω scansh = 66
10078 measured reflectionsk = 1818
2652 independent reflectionsl = 2222
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)] = 0.076Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.147H atoms treated by a mixture of independent and constrained refinement
S = 1.13 w = 1/[σ2(Fo2) + (0.0421P)2 + 0.9028P]
where P = (Fo2 + 2Fc2)/3
2652 reflections(Δ/σ)max < 0.001
212 parametersΔρmax = 0.20 e Å3
0 restraintsΔρmin = 0.21 e Å3
Special details top

Experimental. Crystals desolvate on removal from solvent. Crystals shatter on contact with the cold-stream, data collected from shattered remains of a large needle.

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
O10.8377 (4)0.34174 (15)0.13207 (12)0.0352 (6)
N10.9605 (5)0.27153 (17)0.03492 (13)0.0269 (7)
N20.7442 (6)0.4022 (2)0.02286 (18)0.0389 (8)
C10.9582 (6)0.2604 (2)0.04138 (17)0.0283 (8)
C21.1325 (6)0.3027 (2)0.07952 (18)0.0338 (9)
H21.25000.34200.05600.041*
C31.1349 (7)0.2874 (2)0.15231 (19)0.0396 (10)
H31.25470.31630.17870.047*
C40.9643 (7)0.2305 (2)0.18686 (19)0.0401 (10)
H40.96750.21990.23670.048*
C50.7880 (7)0.1887 (2)0.14856 (18)0.0381 (9)
H50.66950.15010.17270.046*
C60.7827 (6)0.2026 (2)0.07482 (17)0.0300 (8)
C70.6026 (6)0.1580 (2)0.02990 (18)0.0359 (9)
H7A0.47070.12880.06200.043*
H7B0.51790.20230.00220.043*
C80.7257 (6)0.0909 (2)0.02226 (18)0.0323 (9)
H8A0.59330.06870.05150.039*
H8B0.78070.04160.00640.039*
C90.9487 (6)0.1180 (2)0.07306 (17)0.0293 (8)
C101.0615 (7)0.0537 (2)0.11878 (18)0.0339 (9)
H100.99280.00320.11610.041*
C111.2663 (7)0.0695 (2)0.16708 (18)0.0359 (9)
H111.33610.02430.19710.043*
C121.3711 (6)0.1524 (2)0.17175 (17)0.0348 (9)
H121.51370.16420.20460.042*
C131.2646 (6)0.2175 (2)0.12785 (17)0.0318 (9)
H131.33460.27420.13070.038*
C141.0568 (6)0.2006 (2)0.07973 (17)0.0259 (8)
C150.8450 (6)0.3395 (2)0.06550 (18)0.0302 (8)
O20.5016 (5)0.41693 (15)0.19878 (12)0.0353 (6)
O30.4298 (5)0.51232 (18)0.10996 (14)0.0588 (8)
C160.3724 (7)0.4812 (2)0.1662 (2)0.0378 (9)
C170.1550 (7)0.5111 (2)0.2049 (2)0.0425 (10)
H17A0.19960.56550.23000.064*
H17B0.11480.46700.23980.064*
H17C0.00770.52060.17040.064*
H1N0.748 (6)0.405 (2)0.0237 (19)0.034 (10)*
H2N0.651 (7)0.446 (3)0.045 (2)0.054 (12)*
H10.639 (7)0.394 (3)0.168 (2)0.069 (13)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0502 (16)0.0310 (14)0.0239 (14)0.0104 (12)0.0007 (11)0.0023 (11)
N10.0389 (17)0.0192 (15)0.0227 (16)0.0021 (13)0.0026 (13)0.0008 (12)
N20.060 (2)0.0302 (18)0.0265 (19)0.0166 (16)0.0036 (16)0.0037 (15)
C10.032 (2)0.0286 (19)0.025 (2)0.0085 (16)0.0036 (16)0.0005 (15)
C20.041 (2)0.0265 (19)0.034 (2)0.0043 (17)0.0023 (17)0.0041 (16)
C30.049 (2)0.036 (2)0.036 (2)0.0054 (19)0.0129 (19)0.0094 (18)
C40.060 (3)0.037 (2)0.023 (2)0.013 (2)0.0055 (19)0.0003 (18)
C50.054 (3)0.030 (2)0.028 (2)0.0061 (18)0.0047 (18)0.0022 (17)
C60.036 (2)0.027 (2)0.026 (2)0.0050 (16)0.0037 (16)0.0007 (15)
C70.039 (2)0.033 (2)0.035 (2)0.0004 (17)0.0015 (17)0.0048 (17)
C80.037 (2)0.028 (2)0.033 (2)0.0027 (16)0.0076 (16)0.0039 (16)
C90.037 (2)0.030 (2)0.0217 (18)0.0002 (17)0.0110 (16)0.0035 (15)
C100.049 (2)0.025 (2)0.029 (2)0.0012 (17)0.0092 (18)0.0013 (16)
C110.047 (2)0.035 (2)0.026 (2)0.0090 (19)0.0043 (17)0.0059 (17)
C120.037 (2)0.042 (2)0.0250 (19)0.0036 (18)0.0008 (16)0.0018 (18)
C130.042 (2)0.0252 (19)0.029 (2)0.0006 (17)0.0040 (17)0.0022 (16)
C140.031 (2)0.0233 (19)0.0239 (18)0.0027 (15)0.0064 (15)0.0007 (15)
C150.039 (2)0.0253 (19)0.026 (2)0.0005 (17)0.0006 (16)0.0044 (17)
O20.0461 (16)0.0282 (14)0.0317 (14)0.0075 (12)0.0035 (12)0.0018 (12)
O30.089 (2)0.0520 (19)0.0378 (17)0.0340 (16)0.0187 (15)0.0141 (14)
C160.050 (2)0.030 (2)0.032 (2)0.0059 (19)0.0056 (18)0.0054 (18)
C170.048 (2)0.034 (2)0.045 (2)0.0091 (19)0.0025 (19)0.0023 (19)
Geometric parameters (Å, º) top
O1—C151.252 (4)C8—C91.510 (4)
N1—C151.366 (4)C8—H8A0.9900
N1—C11.439 (4)C8—H8B0.9900
N1—C141.445 (4)C9—C141.398 (4)
N2—C151.335 (4)C9—C101.409 (5)
N2—H1N0.88 (3)C10—C111.373 (5)
N2—H2N0.95 (4)C10—H100.9500
C1—C21.383 (4)C11—C121.395 (5)
C1—C61.397 (4)C11—H110.9500
C2—C31.385 (5)C12—C131.385 (5)
C2—H20.9500C12—H120.9500
C3—C41.381 (5)C13—C141.386 (4)
C3—H30.9500C13—H130.9500
C4—C51.388 (5)O2—C161.324 (4)
C4—H40.9500O2—H11.03 (4)
C5—C61.401 (5)O3—C161.221 (4)
C5—H50.9500C16—C171.489 (5)
C6—C71.497 (5)C17—H17A0.9800
C7—C81.530 (5)C17—H17B0.9800
C7—H7A0.9900C17—H17C0.9800
C7—H7B0.9900
C15—N1—C1122.9 (3)C7—C8—H8B107.6
C15—N1—C14119.1 (3)H8A—C8—H8B107.0
C1—N1—C14117.3 (3)C14—C9—C10116.0 (3)
C15—N2—H1N126 (2)C14—C9—C8127.0 (3)
C15—N2—H2N117 (2)C10—C9—C8117.1 (3)
H1N—N2—H2N117 (3)C11—C10—C9123.0 (3)
C2—C1—C6121.3 (3)C11—C10—H10118.5
C2—C1—N1120.7 (3)C9—C10—H10118.5
C6—C1—N1117.9 (3)C10—C11—C12119.5 (3)
C1—C2—C3119.6 (3)C10—C11—H11120.2
C1—C2—H2120.2C12—C11—H11120.2
C3—C2—H2120.2C13—C12—C11119.2 (3)
C4—C3—C2120.5 (3)C13—C12—H12120.4
C4—C3—H3119.8C11—C12—H12120.4
C2—C3—H3119.8C12—C13—C14120.6 (3)
C3—C4—C5119.9 (3)C12—C13—H13119.7
C3—C4—H4120.1C14—C13—H13119.7
C5—C4—H4120.1C13—C14—C9121.8 (3)
C4—C5—C6120.8 (3)C13—C14—N1117.1 (3)
C4—C5—H5119.6C9—C14—N1121.1 (3)
C6—C5—H5119.6O1—C15—N2122.0 (3)
C1—C6—C5118.0 (3)O1—C15—N1119.6 (3)
C1—C6—C7118.4 (3)N2—C15—N1118.4 (3)
C5—C6—C7123.6 (3)C16—O2—H1111 (2)
C6—C7—C8114.3 (3)O3—C16—O2122.2 (3)
C6—C7—H7A108.7O3—C16—C17124.2 (3)
C8—C7—H7A108.7O2—C16—C17113.6 (3)
C6—C7—H7B108.7C16—C17—H17A109.5
C8—C7—H7B108.7C16—C17—H17B109.5
H7A—C7—H7B107.6H17A—C17—H17B109.5
C9—C8—C7118.8 (3)C16—C17—H17C109.5
C9—C8—H8A107.6H17A—C17—H17C109.5
C7—C8—H8A107.6H17B—C17—H17C109.5
C9—C8—H8B107.6
C15—N1—C1—C283.9 (4)C14—C9—C10—C110.4 (5)
C14—N1—C1—C2105.5 (3)C8—C9—C10—C11179.5 (3)
C15—N1—C1—C699.1 (4)C9—C10—C11—C120.3 (5)
C14—N1—C1—C671.4 (4)C10—C11—C12—C130.5 (5)
C6—C1—C2—C30.3 (5)C11—C12—C13—C140.1 (5)
N1—C1—C2—C3176.6 (3)C12—C13—C14—C90.6 (5)
C1—C2—C3—C40.1 (5)C12—C13—C14—N1178.8 (3)
C2—C3—C4—C50.4 (5)C10—C9—C14—C130.8 (5)
C3—C4—C5—C60.8 (5)C8—C9—C14—C13179.0 (3)
C2—C1—C6—C50.1 (5)C10—C9—C14—N1178.9 (3)
N1—C1—C6—C5177.1 (3)C8—C9—C14—N10.9 (5)
C2—C1—C6—C7178.9 (3)C15—N1—C14—C1369.1 (4)
N1—C1—C6—C72.0 (4)C1—N1—C14—C13120.0 (3)
C4—C5—C6—C10.7 (5)C15—N1—C14—C9112.7 (4)
C4—C5—C6—C7178.3 (3)C1—N1—C14—C958.2 (4)
C1—C6—C7—C869.5 (4)C1—N1—C15—O1174.6 (3)
C5—C6—C7—C8109.5 (4)C14—N1—C15—O14.2 (5)
C6—C7—C8—C953.4 (4)C1—N1—C15—N25.8 (5)
C7—C8—C9—C141.7 (5)C14—N1—C15—N2176.2 (3)
C7—C8—C9—C10178.2 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H1···O11.03 (4)1.53 (4)2.547 (3)167 (4)
N2—H1N···O3i0.88 (4)2.20 (3)2.894 (4)136 (3)
N2—H2N···O30.95 (4)2.04 (4)2.970 (4)164 (4)
Symmetry code: (i) x+1, y+1, z.
 

Acknowledgements

The authors thank the Basic Technology Programme of the UK Research Councils for funding this work under the project Control and Prediction of the Organic Solid State (https://www.cposs.org.uk).

References

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