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

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ISSN: 2056-9890

e,e-trans-Cyclo­hexane-1,4-carb­­oxy­lic acid–hexa­methyl­ene­tetra­mine (1/2)

aMolecular Sciences Institute, School of Chemistry, University of the Witwatersrand, Private Bag 3, PO WITS, 2050, Johannesburg, South Africa
*Correspondence e-mail: andreas.lemmerer@wits.ac.za

(Received 21 December 2010; accepted 21 December 2010; online 8 January 2011)

The asymmetric unit of the title compound, 2C6H12N4·C8H12O4, contains one half-mol­ecule of e,e-trans-cyclo­hexane-1,4-dicarb­oxy­lic acid (the complete molecule being generated by inversion symmetry) and one mol­ecule of hexa­methyl­ene­tetra­mine (HMTA), which are connected by O—H⋯N hydrogen bonds. This forms isolated trimers that pack in a herringbone fashion.

Related literature

For related co-crystals featuring one hydrogen bond to HMTA, see: Feng et al. (2006[Feng, H., Zhang, H.-M., Tu, B. & Jin, Z.-M. (2006). Acta Cryst. E62, o3122-o3123.]); Li et al. (2001[Li, W., Zhang, J.-P., Tong, M.-L. & Chen, X.-M. (2001). Aust. J. Chem. 54, 213-217.]); Mak et al. (1986[Mak, T. C. W., Xiaoming, C., Kailiang, S., Jiaxing, Y. & Chaode, Z. (1986). J. Crystallogr. Spectrosc. Res. 16, 639-646.]). For related co-crystals featuring two hydrogen bonds to HMTA, see: Coupar et al. (1997a[Coupar, P. I., Glidewell, C. & Ferguson, G. (1997a). Acta Cryst. B53, 521-533.]); Gardon et al. (2003[Gardon, M., Pinheiro, C. B. & Chapuis, G. (2003). Acta Cryst. B59, 527-536.]); Ghosh et al. (2005[Ghosh, K., Datta, M., Fröhlich, R. & Ganguly, N. C. (2005). J. Mol. Struct. 737, 201-206.]). For related co-crystals featuring three hydrogen bonds to HMTA, see: Coupar et al. (1997b[Coupar, P. I., Ferguson, G., Glidewell, C. & Meehan, P. R. (1997b). Acta Cryst. C53, 1978-1980.]); De Bruyn et al. (1996[Bruyn, P. J. de, Gable, R. W., Potter, A. C. & Solomon, D. H. (1996). Acta Cryst. C52, 466-468.]); Jordan & Mak (1970[Jordan, T. H. & Mak, T. C. W. (1970). J. Chem. Phys. 52, 3790-3794.]). For related co-crystals featuring four hydrogen bonds to HMTA, see: Daka & Wheeler (2006[Daka, P. & Wheeler, K. A. (2006). Acta Cryst. E62, o5477-o5479.]); MacLean et al. (1999[MacLean, E. J., Glidewell, C., Ferguson, G., Gregson, R. M. & Lough, A. J. (1999). Acta Cryst. C55, 1867-1870.]); Zakaria et al. (2003[Zakaria, C. M., Ferguson, G., Lough, A. J. & Glidewell, C. (2003). Acta Cryst. B59, 118-131.]).

[Scheme 1]

Experimental

Crystal data
  • 2C6H12N4·C8H12O4

  • Mr = 452.57

  • Monoclinic, P 21 /n

  • a = 5.9182 (1) Å

  • b = 31.5242 (6) Å

  • c = 6.1193 (1) Å

  • β = 109.144 (1)°

  • V = 1078.52 (3) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.1 mm−1

  • T = 173 K

  • 0.4 × 0.35 × 0.04 mm

Data collection
  • Bruker APEXII CCD area-detector diffractometer

  • Absorption correction: integration (XPREP; Bruker, 2004[Bruker (2004). SAINT-Plus including XPREP. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.960, Tmax = 0.996

  • 13851 measured reflections

  • 2594 independent reflections

  • 2218 reflections with I > 2σ(I)

  • Rint = 0.045

Refinement
  • R[F2 > 2σ(F2)] = 0.040

  • wR(F2) = 0.113

  • S = 0.89

  • 2594 reflections

  • 146 parameters

  • H-atom parameters constrained

  • Δρmax = 0.39 e Å−3

  • Δρmin = −0.19 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O1—H1⋯N1 0.84 1.84 2.6710 (12) 170

Data collection: APEX2 (Bruker, 2005[Bruker (2005). APEX2. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT-Plus (Bruker, 2004[Bruker (2004). SAINT-Plus including XPREP. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT-Plus and XPREP (Bruker 2004[Bruker (2004). SAINT-Plus including XPREP. Bruker AXS Inc., Madison, Wisconsin, USA.]); 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, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and DIAMOND (Brandenburg, 1999[Brandenburg, K. (1999). DIAMOND. Crystal Impact GbR, Bonn, Germany.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Comment top

The molecule hexamethylenetetramine (HMTA) acts as a good hydrogen bond acceptor for carboxylic acid or phenol hydrogen bond donors to make binary co-crystals. HMTA can accept any number from one to four hydrogen bonds due to its tetravalent hydrogen bond acceptors, the lone pairs on each of the four N atoms. Most common are two hydrogen bonds per HMTA molecule (Coupar et al., 1997a; Gardon et al., 2003; Ghosh et al., 2005.), with a smaller frequency of one, three or four hydrogen bonds (Coupar et al., 1997b; Daka & Wheeler, 2006; De Bruyn et al., 1996; Feng et al., 2006; Jordan & Mak, 1970; Li et al., 2001; MacLean et al., 1999; Mak et al., 1986; Zakaria et al., 2003.). The title compound is an example of HMTA only accepting one hydrogen bond. As the cis-cyclohexane-1,4-dicarboxylic acid (CHDA) molecule has two carboxylic acid groups, the observed hydrogen bonded assembly is dumb-bell shaped, where one central CHDA molecule (the bar) hydrogen bonds to two pendant HMTA molecules (the bells) (Fig. 2). The dumb-bell trimers are situated on a centre of inversion, located at the centre of the CHDA molecule. The dumbells pack in a herring-bone fashion (Fig. 3).

Related literature top

For related co-crystals featuring one hydrogen bond to HMTA, see: Feng et al. (2006); Li et al. (2001); Mak et al. (1986). For related co-crystals featuring two hydrogen bonds to HMTA, see: Coupar et al. (1997a); Gardon et al. (2003); Ghosh et al. (2005). For related co-crystals featuring three hydrogen bonds to HMTA, see: Coupar et al. (1997b); De Bruyn et al. (1996); Jordan & Mak (1970). For related co-crystals featuring four hydrogen bonds to HMTA, see: Daka & Wheeler (2006); MacLean et al. (1999); Zakaria et al. (2003).

Experimental top

Crystals where grown by slow evaporation at ambient conditions of a methanol solution containing a 2:1 stoichiometric quantity of hexamethylenetetramine and cis-1,4-cyclohexanecarboxylic acid.

Refinement top

The C-bound H atoms were geometrically placed with C—H bond lengths of 1.00Å for methine CH and 0.99Å for ethylene CH2 and refined as riding with Uiso(H) = 1.2Ueq(C). The O-bound H atom was geometrically placed (O—H bond length 0.84 Å) and refined as riding with Uiso(H) = 1.5Ueq(O).

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT-Plus (Bruker, 2004); data reduction: SAINT-Plus and XPREP (Bruker 2004); 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, 1997) and DIAMOND (Brandenburg, 1999); software used to prepare material for publication: WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. View of (I) (50% probability displacement ellipsoids). Symmetry code: (i):2 - x, 1 - y, 2 - z.
[Figure 2] Fig. 2. Hydrogen bonded centrosymmetric trimers formed by simple hydrogen bonds (red dashed lines) between one CHDA and two HMTA molecules.
[Figure 3] Fig. 3. Packing diagram of the trimers viewed down the c axis.
e,etrans-Cyclohexane-1,4-carboxylic acid–hexamethylenetetramine (1/2) top
Crystal data top
2C6H12N4·C8H12O4F(000) = 488
Mr = 452.57Dx = 1.394 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 5661 reflections
a = 5.9182 (1) Åθ = 3.7–28.3°
b = 31.5242 (6) ŵ = 0.1 mm1
c = 6.1193 (1) ÅT = 173 K
β = 109.144 (1)°Plate, colourless
V = 1078.52 (3) Å30.4 × 0.35 × 0.04 mm
Z = 2
Data collection top
Bruker APEXII CCD area-detector
diffractometer
2218 reflections with I > 2σ(I)
ω scansRint = 0.045
Absorption correction: integration
(XPREP; Bruker, 2004)
θmax = 28.0°, θmin = 1.3°
Tmin = 0.960, Tmax = 0.996h = 77
13851 measured reflectionsk = 4141
2594 independent reflectionsl = 88
Refinement top
Refinement on F20 restraints
Least-squares matrix: fullH-atom parameters constrained
R[F2 > 2σ(F2)] = 0.040 w = 1/[σ2(Fo2) + (0.0739P)2 + 0.3667P]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.113(Δ/σ)max = 0.001
S = 0.89Δρmax = 0.39 e Å3
2594 reflectionsΔρmin = 0.19 e Å3
146 parameters
Crystal data top
2C6H12N4·C8H12O4V = 1078.52 (3) Å3
Mr = 452.57Z = 2
Monoclinic, P21/nMo Kα radiation
a = 5.9182 (1) ŵ = 0.1 mm1
b = 31.5242 (6) ÅT = 173 K
c = 6.1193 (1) Å0.4 × 0.35 × 0.04 mm
β = 109.144 (1)°
Data collection top
Bruker APEXII CCD area-detector
diffractometer
2594 independent reflections
Absorption correction: integration
(XPREP; Bruker, 2004)
2218 reflections with I > 2σ(I)
Tmin = 0.960, Tmax = 0.996Rint = 0.045
13851 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0400 restraints
wR(F2) = 0.113H-atom parameters constrained
S = 0.89Δρmax = 0.39 e Å3
2594 reflectionsΔρmin = 0.19 e Å3
146 parameters
Special details top

Experimental. Numerical integration absorption corrections based on indexed crystal faces were applied using the XPREP routine (Bruker, 2004)

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
C10.0247 (2)0.63264 (4)0.4650 (2)0.0246 (3)
H1A0.12140.60940.37070.029*
H1B0.02310.62890.62610.029*
C20.1335 (2)0.67841 (4)0.1382 (2)0.0282 (3)
H2A0.20860.70580.07550.034*
H2B0.23030.65550.0410.034*
C30.2502 (2)0.71082 (4)0.2722 (2)0.0290 (3)
H3A0.17990.73860.21110.035*
H3B0.41550.71010.26670.035*
C40.2168 (2)0.63619 (4)0.2177 (2)0.0282 (3)
H4A0.38180.63480.21170.034*
H4B0.12350.6130.12010.034*
C50.3614 (2)0.66535 (4)0.6002 (2)0.0256 (3)
H5A0.36580.6620.76230.031*
H5B0.52810.66420.59860.031*
C60.0111 (2)0.70746 (4)0.5164 (2)0.0267 (3)
H6A0.01260.70450.6780.032*
H6B0.06210.73520.45740.032*
N10.22317 (16)0.62980 (3)0.45945 (16)0.0202 (2)
N20.13588 (17)0.67350 (3)0.37597 (19)0.0250 (2)
N30.1098 (2)0.67701 (3)0.12396 (18)0.0273 (2)
N40.25799 (18)0.70679 (3)0.51366 (18)0.0257 (2)
C70.76647 (19)0.52006 (3)0.88313 (19)0.0188 (2)
H70.67340.49420.81280.023*
C80.9750 (2)0.52451 (4)0.78814 (19)0.0219 (2)
H8A0.91190.52710.61750.026*
H8B1.06670.55060.8510.026*
C91.1394 (2)0.48596 (4)0.85539 (19)0.0213 (2)
H9A1.05040.46030.78190.026*
H9B1.27580.48970.79730.026*
C100.6008 (2)0.55801 (3)0.8143 (2)0.0212 (2)
O10.47562 (17)0.55861 (3)0.59260 (15)0.0319 (2)
H10.38830.58030.56290.048*
O20.58343 (19)0.58498 (3)0.94835 (17)0.0397 (3)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0217 (5)0.0197 (6)0.0322 (6)0.0004 (4)0.0087 (5)0.0055 (4)
C20.0237 (6)0.0261 (6)0.0265 (6)0.0051 (5)0.0031 (5)0.0042 (5)
C30.0264 (6)0.0249 (6)0.0384 (7)0.0007 (5)0.0145 (5)0.0100 (5)
C40.0356 (7)0.0266 (6)0.0238 (6)0.0119 (5)0.0115 (5)0.0007 (5)
C50.0203 (5)0.0246 (6)0.0253 (6)0.0009 (4)0.0015 (4)0.0010 (4)
C60.0330 (6)0.0203 (6)0.0297 (6)0.0059 (5)0.0143 (5)0.0018 (4)
N10.0193 (5)0.0187 (5)0.0205 (5)0.0044 (3)0.0038 (4)0.0017 (3)
N20.0178 (5)0.0221 (5)0.0353 (6)0.0038 (4)0.0091 (4)0.0049 (4)
N30.0350 (6)0.0273 (6)0.0206 (5)0.0083 (4)0.0104 (4)0.0052 (4)
N40.0247 (5)0.0190 (5)0.0296 (5)0.0022 (4)0.0037 (4)0.0008 (4)
C70.0179 (5)0.0154 (5)0.0212 (5)0.0034 (4)0.0039 (4)0.0004 (4)
C80.0242 (6)0.0216 (5)0.0206 (5)0.0059 (4)0.0084 (4)0.0050 (4)
C90.0216 (5)0.0220 (6)0.0218 (5)0.0056 (4)0.0090 (4)0.0026 (4)
C100.0183 (5)0.0181 (5)0.0246 (6)0.0025 (4)0.0037 (4)0.0006 (4)
O10.0369 (5)0.0259 (5)0.0249 (5)0.0161 (4)0.0007 (4)0.0002 (3)
O20.0487 (6)0.0305 (5)0.0306 (5)0.0201 (4)0.0002 (4)0.0064 (4)
Geometric parameters (Å, º) top
C1—N21.4676 (14)C5—H5B0.99
C1—N11.4808 (15)C6—N21.4663 (16)
C1—H1A0.99C6—N41.4671 (16)
C1—H1B0.99C6—H6A0.99
C2—N21.4678 (17)C6—H6B0.99
C2—N31.4713 (17)C7—C101.5160 (15)
C2—H2A0.99C7—C9i1.5238 (15)
C2—H2B0.99C7—C81.5331 (15)
C3—N31.4679 (17)C7—H71
C3—N41.4686 (16)C8—C91.5268 (15)
C3—H3A0.99C8—H8A0.99
C3—H3B0.99C8—H8B0.99
C4—N31.4657 (15)C9—C7i1.5238 (15)
C4—N11.4812 (15)C9—H9A0.99
C4—H4A0.99C9—H9B0.99
C4—H4B0.99C10—O21.2091 (15)
C5—N41.4662 (15)C10—O11.3154 (14)
C5—N11.4848 (15)O1—H10.84
C5—H5A0.99
N2—C1—N1111.82 (9)H6A—C6—H6B107.8
N2—C1—H1A109.3C1—N1—C4108.27 (9)
N1—C1—H1A109.3C1—N1—C5107.61 (9)
N2—C1—H1B109.3C4—N1—C5107.78 (9)
N1—C1—H1B109.3C6—N2—C1108.39 (9)
H1A—C1—H1B107.9C6—N2—C2107.89 (9)
N2—C2—N3112.54 (9)C1—N2—C2108.14 (9)
N2—C2—H2A109.1C4—N3—C3108.13 (10)
N3—C2—H2A109.1C4—N3—C2107.97 (10)
N2—C2—H2B109.1C3—N3—C2107.96 (9)
N3—C2—H2B109.1C5—N4—C6107.94 (9)
H2A—C2—H2B107.8C5—N4—C3108.17 (10)
N3—C3—N4112.56 (9)C6—N4—C3107.91 (9)
N3—C3—H3A109.1C10—C7—C9i111.75 (9)
N4—C3—H3A109.1C10—C7—C8110.48 (9)
N3—C3—H3B109.1C9i—C7—C8110.30 (9)
N4—C3—H3B109.1C10—C7—H7108.1
H3A—C3—H3B107.8C9i—C7—H7108.1
N3—C4—N1112.12 (9)C8—C7—H7108.1
N3—C4—H4A109.2C9—C8—C7110.25 (9)
N1—C4—H4A109.2C9—C8—H8A109.6
N3—C4—H4B109.2C7—C8—H8A109.6
N1—C4—H4B109.2C9—C8—H8B109.6
H4A—C4—H4B107.9C7—C8—H8B109.6
N4—C5—N1112.20 (9)H8A—C8—H8B108.1
N4—C5—H5A109.2C7i—C9—C8111.31 (9)
N1—C5—H5A109.2C7i—C9—H9A109.4
N4—C5—H5B109.2C8—C9—H9A109.4
N1—C5—H5B109.2C7i—C9—H9B109.4
H5A—C5—H5B107.9C8—C9—H9B109.4
N2—C6—N4112.61 (9)H9A—C9—H9B108
N2—C6—H6A109.1O2—C10—O1123.03 (11)
N4—C6—H6A109.1O2—C10—C7123.88 (10)
N2—C6—H6B109.1O1—C10—C7113.09 (10)
N4—C6—H6B109.1C10—O1—H1109.5
N2—C1—N1—C457.93 (12)N2—C2—N3—C458.78 (12)
N2—C1—N1—C558.31 (12)N2—C2—N3—C357.91 (12)
N3—C4—N1—C157.99 (13)N1—C5—N4—C658.47 (13)
N3—C4—N1—C558.15 (13)N1—C5—N4—C358.05 (13)
N4—C5—N1—C158.63 (12)N2—C6—N4—C558.39 (12)
N4—C5—N1—C457.94 (12)N2—C6—N4—C358.29 (12)
N4—C6—N2—C158.57 (13)N3—C3—N4—C558.48 (12)
N4—C6—N2—C258.32 (12)N3—C3—N4—C658.06 (12)
N1—C1—N2—C658.43 (13)C10—C7—C8—C9179.28 (9)
N1—C1—N2—C258.29 (12)C9i—C7—C8—C956.67 (13)
N3—C2—N2—C658.06 (12)C7—C8—C9—C7i57.25 (13)
N3—C2—N2—C158.99 (12)C9i—C7—C10—O213.98 (17)
N1—C4—N3—C358.54 (13)C8—C7—C10—O2109.24 (14)
N1—C4—N3—C258.04 (13)C9i—C7—C10—O1165.62 (10)
N4—C3—N3—C458.70 (13)C8—C7—C10—O171.17 (12)
N4—C3—N3—C257.88 (12)
Symmetry code: (i) x+2, y+1, z+2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···N10.841.842.6710 (12)170

Experimental details

Crystal data
Chemical formula2C6H12N4·C8H12O4
Mr452.57
Crystal system, space groupMonoclinic, P21/n
Temperature (K)173
a, b, c (Å)5.9182 (1), 31.5242 (6), 6.1193 (1)
β (°) 109.144 (1)
V3)1078.52 (3)
Z2
Radiation typeMo Kα
µ (mm1)0.1
Crystal size (mm)0.4 × 0.35 × 0.04
Data collection
DiffractometerBruker APEXII CCD area-detector
diffractometer
Absorption correctionIntegration
(XPREP; Bruker, 2004)
Tmin, Tmax0.960, 0.996
No. of measured, independent and
observed [I > 2σ(I)] reflections
13851, 2594, 2218
Rint0.045
(sin θ/λ)max1)0.660
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.040, 0.113, 0.89
No. of reflections2594
No. of parameters146
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.39, 0.19

Computer programs: APEX2 (Bruker, 2005), SAINT-Plus (Bruker, 2004), SAINT-Plus and XPREP (Bruker 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997) and DIAMOND (Brandenburg, 1999), WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···N10.841.842.6710 (12)170
 

Acknowledgements

The University of the Witwatersrand and the Mol­ecular Sciences Institute are thanked for providing the infrastructure and financial support to do this work.

References

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