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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 71| Part 10| October 2015| Pages o717-o718
doi:10.1107/S2056989015016345

Crystal structure of ammonium (3,5-di­chloro­phen­­oxy)acetate hemihydrate

CROSSMARK_Color_square_no_text.svg
Graham Smitha*

aScience and Engineering Faculty, Queensland University of Technology, GPO Box 2434, Brisbane, Queensland 4001, Australia
*Correspondence e-mail: g.smith@qut.edu.au

Edited by G. S. Nichol, University of Edinburgh, Scotland (Received 22 July 2015; accepted 2 September 2015; online 12 September 2015)

In the structure of the title hydrated salt, NH4+·C8H5Cl2O3−·0.5H2O, where the anion derives from (3,5-di­chloro­phen­oxy)acetic acid, the ammonium cation is involved in extensive N—H⋯O hydrogen bonding with both carboxyl­ate and ether O-atom acceptors giving sheet structures lying parallel to (100). The water mol­ecule of solvation lies on a crystallographic twofold rotation axis and is involved in intra-sheet O—H⋯Ocarboxyl­ate hydrogen-bonding inter­actions. In the anion, the oxoacetate side chain assumes an antiperiplanar conformation with the defining C—O—C—C torsion angle = −171.33 (15)°.

CCDC reference: 1421868

1. Related literature

For background on the phen­oxy­acetic acid herbicides, see: Zumdahl (2010[Zumdahl, R. L. (2010). In A History of Weed Science in the United States. New York: Elsevier.]). For examples of structures of a tryptaminium salt and a co-crystalline adduct with (3,5-di­chloro­phen­oxy)acetic acid, see: Smith & Lynch (2015[Smith, G. & Lynch, D. E. (2015). Acta Cryst. E71, 671-674.]); Lynch et al. (2003[Lynch, D. E., Barfield, J., Frost, J., Antrobus, R. & Simmons, J. (2003). Cryst. Eng. 6, 109-122.]). For the structures of ammonium salts of other phen­oxy­acetic acids, see: Liu et al. (2009[Liu, H.-L., Guo, S.-H., Li, Y.-Y. & Jian, F.-F. (2009). Acta Cryst. E65, o1905.]); Smith (2014[Smith, G. (2014). Acta Cryst. E70, 528-532.]).

[Scheme 1]

2. Experimental

2.1. Crystal data

  • NH4+·C8H5Cl2O3−·0.5H2O

  • Mr = 247.07

  • Monoclinic, C 2/c

  • a = 39.818 (3) Å

  • b = 4.3440 (4) Å

  • c = 12.7211 (8) Å

  • β = 98.098 (5)°

  • V = 2178.4 (3) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 0.58 mm−1

  • T = 200 K

  • 0.40 × 0.12 × 0.05 mm

2.2. Data collection

  • Oxford Diffraction Gemini-S CCD-detector diffractometer

  • Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2013[Agilent (2013). CrysAlis PRO. Agilent Technologies Ltd, Yarnton, England.]) Tmin = 0.948, Tmax = 0.980

  • 6680 measured reflections

  • 2146 independent reflections

  • 1832 reflections with I > 2σ(I)

  • Rint = 0.026

2.3. Refinement

  • R[F2 > 2σ(F2)] = 0.034

  • wR(F2) = 0.084

  • S = 1.08

  • 2146 reflections

  • 147 parameters

  • 5 restraints

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

  • Δρmax = 0.21 e Å−3

  • Δρmin = −0.28 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
O1W—H1W⋯O14 0.85 (2) 1.99 (2) 2.822 (2) 166 (2)
N1—H11⋯O11 0.89 (2) 2.50 (2) 3.137 (2) 129 (2)
N1—H11⋯O13 0.89 (2) 1.99 (2) 2.811 (2) 153 (2)
N1—H12⋯O13i 0.88 (2) 2.00 (2) 2.862 (2) 164 (2)
N1—H13⋯O14ii 0.85 (2) 2.03 (2) 2.840 (2) 161 (2)
N1—H14⋯O13iii 0.90 (2) 2.03 (2) 2.894 (2) 161 (2)
Symmetry codes: (i) -x+1, -y+1, -z+1; (ii) [x, -y+1, z-{\script{1\over 2}}]; (iii) x, y+1, z.

Data collection: CrysAlis PRO (Agilent, 2013[Agilent (2013). CrysAlis PRO. Agilent Technologies Ltd, Yarnton, England.]); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SIR92 (Altomare et al., 1993[Altomare, A., Cascarano, G., Giacovazzo, C. & Guagliardi, A. (1993). J. Appl. Cryst. 26, 343-350.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]) within WinGX (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]); molecular graphics: PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: PLATON.

Supporting information

CCDC reference: 1421868

Crystal structure: contains datablocks global, I. DOI: 10.1107/S2056989015016345/nk2232sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S2056989015016345/nk2232Isup2.hkl

Supporting information file. DOI: 10.1107/S2056989015016345/nk2232Isup3.cml

checkCIF report


Comment top

The phenoxy acid (3,5-dichlorophenoxy)acetic acid (3,5-D) is the isomer of the herbicidally active (2,4-dichlorophenoxy)acetic acid (2,4-D) (Zumdahl, 2010). However, unlike 2,4-D the crystallographic literature for 3,5-D is very sparse, comprising only two entries in the Cambridge Structural Database, a 2:1 cocrystal adduct with 4,4'-bipyridine (Lynch et al., 2003) and a tryptaminium salt (Smith & Lynch, 2015). The ammonium salt of 3,5-D, NH4+ C8H5Cl2O3·0.5(H2O), was prepared and the structure is reported herein.

In the title salt (Fig. 1), the ammonium cation is involved in extensive N—H···O hydrogen bonding with both carboxyl and ether O-atom acceptors (Table 1), giving two-dimensional sheet structures lying parallel to (100). (Fig. 2). Among these interactions is a centrosymmetric R44(8) motif conjoined with R44(12) and R21(5) motifs, the last one three-centre asymmetric, involving carboxyl and ether O-atom acceptors. The water molecule of solvation (O1W) lies on a crystallographic twofold rotation axis and is involved in intra-sheet O—H···Ocarboxyl hydrogen-bonding interactions. In this respect, the structure is similar to that of the two-dimensional ammonium salts of the isomeric 2,4-D (Liu et al., 2009) and (4-chloro-2-methylphenoxy)acetic acid (the herbicide MCPA) (Smith, 2014) (both hemihydrates).

The 3,5-DCPA anion is esentially planar with torsion angles C2—C1—O11—C12, C1—O11—C12—C13 and O11—C12—C13—O14 of -175.05 (16), -171.33 (15) and -172.65 (15)° (antiperiplanar), of which the defining angle is the second value (about O11—C12). Although the structure of the parent acid (3,5-D) is not known, the value for the title salt is similar to the one found in the tryptaminium salt [-165.5 (3)°] (Smith & Lynch, 2015) and in the ammonium salts of 2,4-D [171.61 (8)°] (Liu et al., 2009) and MCPA [-173.34 (14)°] (Smith, 2014). However, it contrasts with that of the 2:1 adduct of 3,5-D with 4,4'-bipyridine (Lynch et al., 2003) [71.6 (3)°] (synclinal).

Related literature top

For background on the phenoxyacetic acid herbicides, see: Zumdahl (2010). For examples of structures of a tryptaminium salt and a co-crystalline adduct with (3,5-dichlorophenoxy)acetic acid, see: Smith & Lynch (2015); Lynch et al. (2003). For the structures of ammonium salts of other phenoxyacetic acids, see: Liu et al. (2009); Smith (2014).

Experimental top

The title compound was synthesized by adding 1 M aqueous ammonia solution dropwise to 10 ml of a solution containing 100 mg of (3,5-dichlorophenoxy)acetic acid in 50% ethanol/water. Room temperature evaporation of the solution gave colourless crystal plates of the title salt from which a specimen was cleaved for the X-ray analysis.

Refinement top

Hydrogen atoms of the hemi-water molecule and the ammonium group were located in a difference-Fourier synthesis and were allowed to ride in the refinement with bond distance restraints O—H = 0.90±0.02 Å and N—H = 0.88±0.02 Å and with Uiso(H) = 1.5Ueq(O) or 1.2Ueq(N). All other H atoms were included at calculated sites and allowed to ride with Uiso(H) = 1.2Ueq(C).

Computing details top

Data collection: CrysAlis PRO (Agilent, 2013); cell refinement: CrysAlis PRO (Agilent, 2013); data reduction: CrysAlis PRO (Agilent, 2013); program(s) used to solve structure: SIR92 (Altomare et al., 1993); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008) within WinGX (Farrugia, 2012); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular configuration and atom-numbering scheme for the title hemi-hydrate salt, with non-H atoms shown as 40% probability ellipsoids. The water molecule lies on a twofold rotation axis and inter-species hydrogen bonds are shown as dashed lines.
[Figure 2] Fig. 2. The two-dimensional sheet structure viewed along the b axis, with intramolecular hydrogen bonds shown as dashed lines. For symmetry codes, see Table 1.
Ammonium (3,5-dichlorophenoxy)acetate hemihydrate top
Crystal data top
NH4+·C8H5Cl2O3−·0.5H2OF(000) = 1016
Mr = 247.07Dx = 1.507 Mg m−3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 2066 reflections
a = 39.818 (3) Åθ = 4.1–28.7°
b = 4.3440 (4) ŵ = 0.58 mm−1
c = 12.7211 (8) ÅT = 200 K
β = 98.098 (5)°Prism, colourless
V = 2178.4 (3) Å30.40 × 0.12 × 0.05 mm
Z = 8
Data collection top
Oxford Diffraction Gemini-S CCD-detector
diffractometer		2146 independent reflections
Radiation source: Enhance (Mo) X-ray source1832 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.026
Detector resolution: 16.077 pixels mm-1θmax = 26.0°, θmin = 3.1°
ω scansh = −48→39
Absorption correction: multi-scan
(CrysAlis PRO; Agilent, 2013)		k = −3→5
Tmin = 0.948, Tmax = 0.980l = −15→15
6680 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)] = 0.034Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.084H atoms treated by a mixture of independent and constrained refinement
S = 1.08 w = 1/[σ2(Fo2) + (0.034P)2 + 1.220P]
where P = (Fo2 + 2Fc2)/3
2146 reflections(Δ/σ)max = 0.002
147 parametersΔρmax = 0.21 e Å−3
5 restraintsΔρmin = −0.28 e Å−3
Crystal data top
NH4+·C8H5Cl2O3−·0.5H2OV = 2178.4 (3) Å3
Mr = 247.07Z = 8
Monoclinic, C2/cMo Kα radiation
a = 39.818 (3) ŵ = 0.58 mm−1
b = 4.3440 (4) ÅT = 200 K
c = 12.7211 (8) Å0.40 × 0.12 × 0.05 mm
β = 98.098 (5)°
Data collection top
Oxford Diffraction Gemini-S CCD-detector
diffractometer		2146 independent reflections
Absorption correction: multi-scan
(CrysAlis PRO; Agilent, 2013)		1832 reflections with I > 2σ(I)
Tmin = 0.948, Tmax = 0.980Rint = 0.026
6680 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0345 restraints
wR(F2) = 0.084H atoms treated by a mixture of independent and constrained refinement
S = 1.08Δρmax = 0.21 e Å−3
2146 reflectionsΔρmin = −0.28 e Å−3
147 parameters
Special details top

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 e.s.d.'s 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
Cl30.66552 (1)1.11332 (13)0.31644 (4)0.0401 (2)
Cl50.72836 (1)0.45912 (16)0.64617 (5)0.0517 (2)
O110.59904 (3)0.5049 (3)0.55326 (10)0.0340 (4)
O130.53963 (3)0.2408 (3)0.56560 (10)0.0325 (4)
O140.55624 (4)0.0775 (3)0.73120 (11)0.0384 (5)
C10.63101 (4)0.5896 (4)0.53513 (14)0.0268 (5)
C20.63218 (5)0.7850 (4)0.44879 (14)0.0282 (6)
C30.66354 (5)0.8742 (4)0.42535 (14)0.0288 (6)
C40.69369 (5)0.7798 (5)0.48405 (15)0.0338 (6)
C50.69140 (5)0.5888 (5)0.56904 (15)0.0322 (6)
C60.66063 (4)0.4896 (5)0.59619 (14)0.0280 (6)
C120.59684 (5)0.3252 (5)0.64620 (14)0.0314 (6)
C130.56109 (4)0.2087 (4)0.64708 (14)0.0274 (6)
O1W0.50000−0.3034 (5)0.750000.0456 (8)
N10.53131 (4)0.7283 (5)0.41888 (14)0.0332 (6)
H20.611900.854800.407200.0340*
H40.715000.843900.466500.0410*
H60.659900.356700.655100.0340*
H1210.603700.452300.710200.0380*
H1220.612600.148300.648200.0380*
H1W0.5153 (5)−0.185 (5)0.7335 (17)0.0400*
H110.5403 (5)0.568 (4)0.4560 (15)0.0320*
H120.5089 (4)0.732 (5)0.4100 (15)0.0320*
H130.5406 (5)0.744 (5)0.3632 (13)0.0320*
H140.5370 (5)0.904 (4)0.4539 (15)0.0320*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl30.0507 (3)0.0386 (3)0.0329 (3)−0.0105 (2)0.0122 (2)0.0034 (2)
Cl50.0240 (3)0.0735 (5)0.0549 (4)−0.0024 (3)−0.0035 (2)0.0113 (3)
O110.0217 (7)0.0486 (9)0.0323 (7)−0.0008 (6)0.0055 (5)0.0128 (6)
O130.0252 (7)0.0387 (8)0.0330 (7)−0.0004 (6)0.0020 (6)0.0037 (6)
O140.0370 (8)0.0504 (9)0.0298 (7)−0.0067 (7)0.0112 (6)0.0059 (7)
C10.0240 (9)0.0309 (10)0.0264 (9)−0.0031 (8)0.0066 (7)−0.0046 (8)
C20.0278 (10)0.0319 (11)0.0250 (9)0.0002 (8)0.0040 (7)−0.0012 (8)
C30.0361 (11)0.0264 (10)0.0253 (9)−0.0054 (8)0.0096 (8)−0.0051 (8)
C40.0283 (10)0.0386 (12)0.0361 (11)−0.0098 (9)0.0098 (8)−0.0058 (9)
C50.0239 (10)0.0391 (12)0.0326 (11)−0.0020 (9)0.0002 (8)−0.0054 (9)
C60.0257 (10)0.0334 (11)0.0250 (9)−0.0020 (8)0.0035 (7)−0.0001 (8)
C120.0280 (10)0.0420 (12)0.0239 (9)−0.0028 (9)0.0024 (7)0.0062 (8)
C130.0265 (10)0.0294 (10)0.0277 (10)0.0032 (8)0.0088 (8)−0.0016 (8)
O1W0.0348 (12)0.0361 (13)0.0660 (15)0.00000.0073 (11)0.0000
N10.0282 (9)0.0392 (11)0.0325 (10)0.0027 (8)0.0050 (7)0.0076 (8)
Geometric parameters (Å, º) top
Cl3—C31.7423 (18)C1—C61.387 (2)
Cl5—C51.743 (2)C1—C21.394 (2)
O11—C11.375 (2)C2—C31.380 (3)
O11—C121.430 (2)C3—C41.384 (3)
O13—C131.255 (2)C4—C51.376 (3)
O14—C131.251 (2)C5—C61.388 (3)
O1W—H1Wi0.85 (2)C12—C131.512 (3)
O1W—H1W0.85 (2)C2—H20.9500
N1—H130.847 (18)C4—H40.9500
N1—H120.884 (16)C6—H60.9500
N1—H110.888 (18)C12—H1220.9900
N1—H140.897 (18)C12—H1210.9900
C1—O11—C12116.79 (14)C4—C5—C6122.78 (18)
H1W—O1W—H1Wi105 (2)C1—C6—C5118.31 (17)
H12—N1—H13116.4 (18)O11—C12—C13110.87 (15)
H12—N1—H14103.2 (19)O13—C13—C12119.27 (15)
H11—N1—H12114.0 (19)O13—C13—O14126.01 (16)
H11—N1—H13108.5 (19)O14—C13—C12114.68 (16)
H13—N1—H14103.7 (19)C3—C2—H2121.00
H11—N1—H14110.4 (17)C1—C2—H2121.00
C2—C1—C6120.77 (16)C5—C4—H4121.00
O11—C1—C6123.80 (16)C3—C4—H4122.00
O11—C1—C2115.43 (15)C1—C6—H6121.00
C1—C2—C3118.23 (17)C5—C6—H6121.00
Cl3—C3—C2118.89 (14)O11—C12—H121109.00
Cl3—C3—C4118.22 (15)O11—C12—H122109.00
C2—C3—C4122.89 (17)C13—C12—H121109.00
C3—C4—C5117.02 (18)C13—C12—H122110.00
Cl5—C5—C4119.54 (16)H121—C12—H122108.00
Cl5—C5—C6117.68 (15)
C12—O11—C1—C2−175.05 (16)Cl3—C3—C4—C5−179.42 (15)
C12—O11—C1—C65.6 (3)C2—C3—C4—C50.0 (3)
C1—O11—C12—C13−171.33 (15)C3—C4—C5—Cl5179.67 (15)
O11—C1—C2—C3−178.93 (15)C3—C4—C5—C60.5 (3)
C6—C1—C2—C30.5 (3)Cl5—C5—C6—C1−179.64 (15)
O11—C1—C6—C5179.27 (17)C4—C5—C6—C1−0.4 (3)
C2—C1—C6—C5−0.1 (3)O11—C12—C13—O139.5 (2)
C1—C2—C3—Cl3178.97 (13)O11—C12—C13—O14−172.65 (15)
C1—C2—C3—C4−0.4 (3)
Symmetry code: (i) −x+1, y, −z+3/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1W—H1W···O140.85 (2)1.99 (2)2.822 (2)166 (2)
N1—H11···O110.89 (2)2.50 (2)3.137 (2)129 (2)
N1—H11···O130.89 (2)1.99 (2)2.811 (2)153 (2)
N1—H12···O13ii0.88 (2)2.00 (2)2.862 (2)164 (2)
N1—H13···O14iii0.85 (2)2.03 (2)2.840 (2)161 (2)
N1—H14···O13iv0.90 (2)2.03 (2)2.894 (2)161 (2)
Symmetry codes: (ii) −x+1, −y+1, −z+1; (iii) x, −y+1, z−1/2; (iv) x, y+1, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1W—H1W···O140.85 (2)1.99 (2)2.822 (2)166 (2)
N1—H11···O110.888 (18)2.50 (2)3.137 (2)128.9 (15)
N1—H11···O130.888 (18)1.994 (18)2.811 (2)152.5 (18)
N1—H12···O13i0.884 (16)2.003 (16)2.862 (2)163.7 (17)
N1—H13···O14ii0.847 (18)2.026 (18)2.840 (2)161 (2)
N1—H14···O13iii0.897 (18)2.032 (18)2.894 (2)160.9 (18)
Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) x, −y+1, z−1/2; (iii) x, y+1, z.
 

Acknowledgements

GS acknowledges the support of the Science and Engineering Faculty and the University Library of the Queensland University of Technology.

References

First citationAgilent (2013). CrysAlis PRO. Agilent Technologies Ltd, Yarnton, England.  Google Scholar
 First citationAltomare, A., Cascarano, G., Giacovazzo, C. & Guagliardi, A. (1993). J. Appl. Cryst. 26, 343–350.  CrossRef Web of Science IUCr Journals Google Scholar
 First citationFarrugia, L. J. (2012). J. Appl. Cryst. 45, 849–854.  Web of Science CrossRef CAS IUCr Journals Google Scholar
 First citationLiu, H.-L., Guo, S.-H., Li, Y.-Y. & Jian, F.-F. (2009). Acta Cryst. E65, o1905.  Web of Science CSD CrossRef IUCr Journals Google Scholar
 First citationLynch, D. E., Barfield, J., Frost, J., Antrobus, R. & Simmons, J. (2003). Cryst. Eng. 6, 109–122.  Web of Science CSD CrossRef CAS Google Scholar
 First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar
 First citationSmith, G. (2014). Acta Cryst. E70, 528–532.  CSD CrossRef IUCr Journals Google Scholar
 First citationSmith, G. & Lynch, D. E. (2015). Acta Cryst. E71, 671–674.  CSD CrossRef IUCr Journals Google Scholar
 First citationSpek, A. L. (2009). Acta Cryst. D65, 148–155.  Web of Science CrossRef CAS IUCr Journals Google Scholar
 First citationZumdahl, R. L. (2010). In A History of Weed Science in the United States. New York: Elsevier.  Google Scholar

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Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 71| Part 10| October 2015| Pages o717-o718
doi:10.1107/S2056989015016345
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