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ISSN: 2056-9890

Piperazine-1,4-diium (R)-2-[4-(1-car­b­oxy­l­atometh­­oxy)phen­­oxy]propano­ate

aEngineering Research Center of Pesticides of Heilongjiang University, Heilongjiang University, Harbin 150050, People's Republic of China
*Correspondence e-mail: hgf1000@163.com

(Received 28 May 2012; accepted 15 June 2012; online 20 June 2012)

In the anion of the title mol­ecular salt, C4H12N22+·C11H10O62−, the two acetate groups form torsion angles of 74.1 (1) and 7.1 (1)° with the central benzene ring, and the cation exhibits a chair conformation. In the crystal, N—H⋯O hydrogen bonds link the components into a two-dimensional supra­molecular network lying parallel to the ab plane. A number of C—H⋯O inter­actions consolidate the packing.

Related literature

For the synthesis of the anion, see: Bezwada (2007[Bezwada, R. S. (2007). US Patent No. 2007/0141113 A1.]). For a similar crystal structure containing the same chiral anion, see: Ren et al. (2012[Ren, C.-Y., Hou, G.-F., Yu, Y.-H. & Gao, J.-S. (2012). Acta Cryst. E68, o223.]).

[Scheme 1]

Experimental

Crystal data
  • C4H12N22+·C11H10O62−

  • Mr = 326.35

  • Monoclinic, P 21

  • a = 6.1210 (12) Å

  • b = 18.134 (4) Å

  • c = 7.0006 (14) Å

  • β = 90.22 (3)°

  • V = 777.1 (3) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.11 mm−1

  • T = 293 K

  • 0.56 × 0.22 × 0.17 mm

Data collection
  • Rigaku R-AXIS RAPID diffractometer

  • Absorption correction: multi-scan (ABSCOR; Higashi, 1995[Higashi, T. (1995). ABSCOR. Rigaku Corporation, Tokyo, Japan.]) Tmin = 0.941, Tmax = 0.982

  • 7573 measured reflections

  • 1820 independent reflections

  • 1712 reflections with I > 2σ(I)

  • Rint = 0.029

Refinement
  • R[F2 > 2σ(F2)] = 0.029

  • wR(F2) = 0.074

  • S = 1.07

  • 1820 reflections

  • 209 parameters

  • 1 restraint

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

  • Δρmax = 0.16 e Å−3

  • Δρmin = −0.14 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1A⋯O2 0.90 1.89 2.773 (2) 167
N1—H1B⋯O1i 0.90 1.82 2.681 (2) 160
N2—H2B⋯O5ii 0.90 1.93 2.803 (2) 163
N2—H2A⋯O6iii 0.90 1.85 2.711 (2) 159
C9—H9A⋯O2iv 0.96 2.56 3.419 (3) 150
C12—H12B⋯O6ii 0.97 2.49 3.339 (2) 146
C13—H13A⋯O2v 0.97 2.51 3.216 (2) 130
C14—H14A⋯O1 0.97 2.58 3.429 (3) 147
C15—H15A⋯O6ii 0.97 2.54 3.371 (3) 144
Symmetry codes: (i) x-1, y, z; (ii) [-x, y+{\script{1\over 2}}, -z+2]; (iii) [-x+1, y+{\script{1\over 2}}, -z+2]; (iv) x+1, y, z; (v) x, y, z+1.

Data collection: RAPID-AUTO (Rigaku, 1998[Rigaku (1998). RAPID-AUTO. Rigaku Corporation, Tokyo, Japan.]); cell refinement: RAPID-AUTO; data reduction: CrystalClear (Rigaku/MSC, 2002[Rigaku/MSC (2002). CrystalClear. Rigaku/MSC Inc., The Woodlands, Texas, 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: DIAMOND (Brandenburg, 1999[Brandenburg, K. (1999). DIAMOND. Crystal Impact GbR, Bonn, Germany.]; software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

Hydrogen bonding is the molecular interaction but strong enough and directional, predictability. Recently, chiral ligands become one of the focus in supramolecular research for their wide applications in catalytic and pharmaceutical industry. However, report about chiral carboxylic acid is few (Ren et al. 2012). Herein, we report the synthesis and structure of a new chiral aromatic carboxylic acid contained compound.

The asymmertric unit of title compound, [C11H10O6].[C4H10N2], contains one (R)-2-(4-(1-carboxyethoxy)phenoxy)acetate anion and one piperazine-1,4-diium cation (Fig. 1). One acetate group of the anion twist towards a side of the benzenyl plane with the torsion angles of 74.1 (1) °, while the other is almost conplaner with the benzenyl plane with the torsion angles of 7.1 (1) °. In the crystal, a layer structure parallel to the ab plane is built up by N—H···O hydrogen bonds linking the anions and cations (Fig. 2, Table 1).

Related literature top

For the synthesis of the anion, see: Bezwada (2007). For a similar crystal structure containing the same chiral anion, see: Ren et al. (2012).

Experimental top

(R)-2-(4-(carboxymethoxy)phenoxy)propanoic acid was prepared by the reaction of R-(+)-2-(4-hydroxy-phenoxy)propionic acid and methyl chloroacetate under alkaline condition (Bezwada, 2007). (R)-2-(4-(carboxymethoxy)phenoxy)propanoic acid (0.120 g, 0.5 mmol) and 1,4-diazacyclohexane (0.086 g, 1.0 mmol) were dissolved in ethanol (15 ml). After stirring and filtering, colorless block crystals of title compound were obtained upon slow evaporation of the solvent.

Refinement top

H atoms bound to C atoms were placed in calculated positions and treated as riding on their parent atoms, with C—H = 0.93 – 0.98 Å, and with Uiso(H) = 1.2 / 1.5Ueq(C). The N-bond H atoms were located in a difference Fourier map and refined with the N—H bond distance fixed at 0.90 Å. As no signifigcant anomalous scatterings, Friedel pairs were merged, the enantiomer has been assigned by reference to an unchanging chiral centre in the synthetic procedure.

Structure description top

Hydrogen bonding is the molecular interaction but strong enough and directional, predictability. Recently, chiral ligands become one of the focus in supramolecular research for their wide applications in catalytic and pharmaceutical industry. However, report about chiral carboxylic acid is few (Ren et al. 2012). Herein, we report the synthesis and structure of a new chiral aromatic carboxylic acid contained compound.

The asymmertric unit of title compound, [C11H10O6].[C4H10N2], contains one (R)-2-(4-(1-carboxyethoxy)phenoxy)acetate anion and one piperazine-1,4-diium cation (Fig. 1). One acetate group of the anion twist towards a side of the benzenyl plane with the torsion angles of 74.1 (1) °, while the other is almost conplaner with the benzenyl plane with the torsion angles of 7.1 (1) °. In the crystal, a layer structure parallel to the ab plane is built up by N—H···O hydrogen bonds linking the anions and cations (Fig. 2, Table 1).

For the synthesis of the anion, see: Bezwada (2007). For a similar crystal structure containing the same chiral anion, see: Ren et al. (2012).

Computing details top

Data collection: RAPID-AUTO (Rigaku, 1998); cell refinement: RAPID-AUTO (Rigaku, 1998); data reduction: CrystalClear (Rigaku/MSC, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 1999; software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, showing displacement ellipsoids at the 50% probability level for non-H atoms.
[Figure 2] Fig. 2. A partial packing view, showing 2D layer structure parallel to the ab plane.
Piperazine-1,4-diium (R)-2-[4-(1-carboxylatomethoxy)phenoxy]propanoate top
Crystal data top
C4H12N2+·C11H10O6F(000) = 348
Mr = 326.35Dx = 1.395 Mg m3
Monoclinic, P21Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ybCell parameters from 7107 reflections
a = 6.1210 (12) Åθ = 3.1–27.7°
b = 18.134 (4) ŵ = 0.11 mm1
c = 7.0006 (14) ÅT = 293 K
β = 90.22 (3)°Block, colorless
V = 777.1 (3) Å30.56 × 0.22 × 0.17 mm
Z = 2
Data collection top
Rigaku R-AXIS RAPID
diffractometer
1820 independent reflections
Radiation source: fine-focus sealed tube1712 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.029
ω scanθmax = 27.5°, θmin = 3.1°
Absorption correction: multi-scan
(ABSCOR; Higashi, 1995)
h = 77
Tmin = 0.941, Tmax = 0.982k = 2323
7573 measured reflectionsl = 99
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)] = 0.029Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.074H atoms treated by a mixture of independent and constrained refinement
S = 1.07 w = 1/[σ2(Fo2) + (0.0448P)2 + 0.044P]
where P = (Fo2 + 2Fc2)/3
1820 reflections(Δ/σ)max < 0.001
209 parametersΔρmax = 0.16 e Å3
1 restraintΔρmin = 0.14 e Å3
Crystal data top
C4H12N2+·C11H10O6V = 777.1 (3) Å3
Mr = 326.35Z = 2
Monoclinic, P21Mo Kα radiation
a = 6.1210 (12) ŵ = 0.11 mm1
b = 18.134 (4) ÅT = 293 K
c = 7.0006 (14) Å0.56 × 0.22 × 0.17 mm
β = 90.22 (3)°
Data collection top
Rigaku R-AXIS RAPID
diffractometer
1820 independent reflections
Absorption correction: multi-scan
(ABSCOR; Higashi, 1995)
1712 reflections with I > 2σ(I)
Tmin = 0.941, Tmax = 0.982Rint = 0.029
7573 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0291 restraint
wR(F2) = 0.074H atoms treated by a mixture of independent and constrained refinement
S = 1.07Δρmax = 0.16 e Å3
1820 reflectionsΔρmin = 0.14 e Å3
209 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
N10.1268 (2)0.40697 (9)0.4052 (2)0.0270 (3)
C10.6299 (3)0.20125 (9)0.4334 (3)0.0263 (4)
C20.4140 (3)0.18863 (10)0.3790 (3)0.0298 (4)
H20.36250.20600.26220.036*
C30.2751 (3)0.14978 (11)0.5005 (3)0.0308 (4)
H30.13180.14070.46270.037*
C40.3471 (3)0.12455 (10)0.6762 (3)0.0283 (4)
C50.5625 (3)0.13885 (11)0.7333 (3)0.0295 (4)
H50.61290.12280.85160.035*
C60.7006 (3)0.17731 (10)0.6113 (3)0.0284 (4)
H60.84320.18720.64990.034*
C70.6063 (3)0.34381 (10)0.2006 (2)0.0248 (3)
C80.7166 (3)0.27009 (10)0.1480 (2)0.0264 (4)
H80.61180.23860.08000.032*
C90.9189 (3)0.28043 (12)0.0266 (3)0.0364 (4)
H9A1.02600.30800.09720.055*
H9B0.88090.30680.08780.055*
H9C0.97790.23310.00660.055*
C100.2861 (3)0.04605 (11)0.9413 (3)0.0318 (4)
H10A0.34540.08051.03390.038*
H10B0.40510.01530.89670.038*
C110.1160 (3)0.00256 (11)1.0390 (2)0.0288 (4)
C120.1365 (3)0.35378 (10)0.5670 (3)0.0289 (4)
H12A0.12580.30390.51770.035*
H12B0.01320.36210.65090.035*
C130.3462 (3)0.36176 (10)0.6797 (3)0.0290 (4)
H13A0.34320.32880.78880.035*
H13B0.46890.34790.60010.035*
C140.3647 (3)0.49191 (10)0.5838 (3)0.0306 (4)
H14A0.48680.48310.49900.037*
H14B0.37720.54190.63220.037*
C150.1535 (3)0.48420 (10)0.4733 (3)0.0298 (4)
H15A0.03160.49740.55450.036*
H15B0.15430.51750.36490.036*
H1A0.23310.39620.32120.036*
H1B0.00250.40230.34460.036*
N20.3746 (2)0.43893 (9)0.7465 (2)0.0266 (3)
H2A0.50440.44330.80630.032*
H2B0.26900.44990.83090.032*
O10.7068 (2)0.38740 (8)0.3073 (2)0.0379 (3)
O20.4179 (2)0.35462 (9)0.13462 (19)0.0364 (3)
O30.7876 (2)0.23362 (8)0.32024 (19)0.0330 (3)
O40.1985 (2)0.08598 (8)0.7847 (2)0.0379 (4)
O50.0801 (2)0.00199 (10)0.9952 (2)0.0435 (4)
O60.1969 (2)0.04445 (9)1.1639 (2)0.0371 (3)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0224 (7)0.0360 (8)0.0225 (7)0.0005 (6)0.0015 (6)0.0025 (6)
C10.0257 (9)0.0212 (8)0.0321 (9)0.0000 (6)0.0053 (7)0.0026 (7)
C20.0271 (9)0.0294 (9)0.0330 (9)0.0024 (7)0.0008 (8)0.0079 (7)
C30.0218 (8)0.0309 (9)0.0397 (10)0.0002 (7)0.0006 (7)0.0076 (8)
C40.0259 (9)0.0279 (8)0.0311 (9)0.0014 (7)0.0061 (7)0.0018 (7)
C50.0325 (9)0.0305 (9)0.0256 (8)0.0026 (7)0.0002 (7)0.0022 (7)
C60.0257 (8)0.0290 (9)0.0304 (9)0.0046 (7)0.0004 (7)0.0014 (7)
C70.0218 (8)0.0327 (9)0.0199 (7)0.0026 (7)0.0040 (6)0.0034 (7)
C80.0251 (8)0.0299 (9)0.0241 (8)0.0031 (7)0.0011 (7)0.0002 (7)
C90.0356 (10)0.0412 (10)0.0324 (9)0.0004 (9)0.0118 (8)0.0019 (8)
C100.0288 (9)0.0374 (10)0.0291 (9)0.0068 (8)0.0010 (8)0.0068 (8)
C110.0259 (9)0.0384 (10)0.0221 (7)0.0067 (7)0.0031 (7)0.0034 (7)
C120.0311 (9)0.0263 (9)0.0294 (8)0.0040 (7)0.0028 (7)0.0015 (7)
C130.0328 (9)0.0286 (9)0.0255 (8)0.0046 (7)0.0016 (7)0.0007 (7)
C140.0318 (9)0.0282 (9)0.0317 (9)0.0053 (7)0.0009 (8)0.0005 (7)
C150.0318 (9)0.0289 (8)0.0287 (8)0.0029 (7)0.0030 (7)0.0021 (7)
N20.0236 (7)0.0338 (8)0.0224 (7)0.0025 (6)0.0023 (6)0.0047 (6)
O10.0286 (7)0.0421 (8)0.0431 (8)0.0002 (6)0.0032 (6)0.0138 (6)
O20.0243 (6)0.0516 (9)0.0332 (7)0.0050 (6)0.0037 (5)0.0028 (6)
O30.0241 (6)0.0382 (7)0.0366 (7)0.0022 (5)0.0033 (5)0.0122 (6)
O40.0264 (7)0.0482 (9)0.0390 (7)0.0062 (6)0.0012 (6)0.0184 (6)
O50.0255 (7)0.0660 (10)0.0389 (7)0.0083 (7)0.0014 (6)0.0202 (7)
O60.0294 (7)0.0485 (8)0.0335 (7)0.0044 (6)0.0007 (6)0.0145 (6)
Geometric parameters (Å, º) top
N1—C151.488 (2)C9—H9B0.9600
N1—C121.489 (2)C9—H9C0.9600
N1—H1A0.9004C10—O41.418 (2)
N1—H1B0.9000C10—C111.528 (2)
C1—O31.382 (2)C10—H10A0.9700
C1—C61.387 (3)C10—H10B0.9700
C1—C21.393 (3)C11—O51.240 (2)
C2—C31.396 (3)C11—O61.259 (2)
C2—H20.9300C12—C131.510 (3)
C3—C41.383 (3)C12—H12A0.9700
C3—H30.9300C12—H12B0.9700
C4—O41.378 (2)C13—N21.486 (2)
C4—C51.400 (3)C13—H13A0.9700
C5—C61.391 (2)C13—H13B0.9700
C5—H50.9300C14—N21.491 (2)
C6—H60.9300C14—C151.510 (3)
C7—O11.248 (2)C14—H14A0.9700
C7—O21.256 (2)C14—H14B0.9700
C7—C81.543 (3)C15—H15A0.9700
C8—O31.441 (2)C15—H15B0.9700
C8—C91.516 (2)N2—H2A0.9000
C8—H80.9800N2—H2B0.9000
C9—H9A0.9600
C15—N1—C12111.22 (13)O4—C10—H10A109.1
C15—N1—H1A109.5C11—C10—H10A109.1
C12—N1—H1A109.2O4—C10—H10B109.1
C15—N1—H1B109.5C11—C10—H10B109.1
C12—N1—H1B109.3H10A—C10—H10B107.8
H1A—N1—H1B108.0O5—C11—O6126.13 (17)
O3—C1—C6115.57 (16)O5—C11—C10120.76 (16)
O3—C1—C2125.27 (17)O6—C11—C10113.11 (16)
C6—C1—C2119.09 (16)N1—C12—C13111.51 (15)
C1—C2—C3119.75 (17)N1—C12—H12A109.3
C1—C2—H2120.1C13—C12—H12A109.3
C3—C2—H2120.1N1—C12—H12B109.3
C4—C3—C2121.06 (17)C13—C12—H12B109.3
C4—C3—H3119.5H12A—C12—H12B108.0
C2—C3—H3119.5N2—C13—C12110.66 (15)
O4—C4—C3116.66 (16)N2—C13—H13A109.5
O4—C4—C5124.07 (17)C12—C13—H13A109.5
C3—C4—C5119.27 (16)N2—C13—H13B109.5
C6—C5—C4119.44 (16)C12—C13—H13B109.5
C6—C5—H5120.3H13A—C13—H13B108.1
C4—C5—H5120.3N2—C14—C15111.32 (15)
C1—C6—C5121.35 (17)N2—C14—H14A109.4
C1—C6—H6119.3C15—C14—H14A109.4
C5—C6—H6119.3N2—C14—H14B109.4
O1—C7—O2124.82 (17)C15—C14—H14B109.4
O1—C7—C8118.46 (16)H14A—C14—H14B108.0
O2—C7—C8116.70 (16)N1—C15—C14110.13 (15)
O3—C8—C9106.36 (15)N1—C15—H15A109.6
O3—C8—C7109.18 (14)C14—C15—H15A109.6
C9—C8—C7112.70 (16)N1—C15—H15B109.6
O3—C8—H8109.5C14—C15—H15B109.6
C9—C8—H8109.5H15A—C15—H15B108.1
C7—C8—H8109.5C13—N2—C14111.23 (13)
C8—C9—H9A109.5C13—N2—H2A109.4
C8—C9—H9B109.5C14—N2—H2A109.4
H9A—C9—H9B109.5C13—N2—H2B109.4
C8—C9—H9C109.5C14—N2—H2B109.4
H9A—C9—H9C109.5H2A—N2—H2B108.0
H9B—C9—H9C109.5C1—O3—C8117.74 (14)
O4—C10—C11112.61 (15)C4—O4—C10115.88 (15)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1A···O20.901.892.773 (2)167
N1—H1B···O1i0.901.822.681 (2)160
N2—H2B···O5ii0.901.932.803 (2)163
N2—H2A···O6iii0.901.852.711 (2)159
C9—H9A···O2iv0.962.563.419 (3)150
C12—H12B···O6ii0.972.493.339 (2)146
C13—H13A···O2v0.972.513.216 (2)130
C14—H14A···O10.972.583.429 (3)147
C15—H15A···O6ii0.972.543.371 (3)144
Symmetry codes: (i) x1, y, z; (ii) x, y+1/2, z+2; (iii) x+1, y+1/2, z+2; (iv) x+1, y, z; (v) x, y, z+1.

Experimental details

Crystal data
Chemical formulaC4H12N2+·C11H10O6
Mr326.35
Crystal system, space groupMonoclinic, P21
Temperature (K)293
a, b, c (Å)6.1210 (12), 18.134 (4), 7.0006 (14)
β (°) 90.22 (3)
V3)777.1 (3)
Z2
Radiation typeMo Kα
µ (mm1)0.11
Crystal size (mm)0.56 × 0.22 × 0.17
Data collection
DiffractometerRigaku R-AXIS RAPID
Absorption correctionMulti-scan
(ABSCOR; Higashi, 1995)
Tmin, Tmax0.941, 0.982
No. of measured, independent and
observed [I > 2σ(I)] reflections
7573, 1820, 1712
Rint0.029
(sin θ/λ)max1)0.649
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.029, 0.074, 1.07
No. of reflections1820
No. of parameters209
No. of restraints1
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.16, 0.14

Computer programs: RAPID-AUTO (Rigaku, 1998), CrystalClear (Rigaku/MSC, 2002), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg, 1999.

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1A···O20.901.892.773 (2)167
N1—H1B···O1i0.901.822.681 (2)160
N2—H2B···O5ii0.901.932.803 (2)163
N2—H2A···O6iii0.901.852.711 (2)159
C9—H9A···O2iv0.962.563.419 (3)150
C12—H12B···O6ii0.972.493.339 (2)146
C13—H13A···O2v0.972.513.216 (2)130
C14—H14A···O10.972.583.429 (3)147
C15—H15A···O6ii0.972.543.371 (3)144
Symmetry codes: (i) x1, y, z; (ii) x, y+1/2, z+2; (iii) x+1, y+1/2, z+2; (iv) x+1, y, z; (v) x, y, z+1.
 

Acknowledgements

This research was supported by research funds for the Science and Technology Planning Project of Heilongjiang Province (PG09J001). We thank also Heilongjiang University for supporting this study.

References

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