tert-Butyl­aminium 2-carb­oxy-4,5-dichloro­benzoate

Smith, G.; Wermuth, U.D.

doi:10.1107/S1600536811034131

organic compounds

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ISSN: 2056-9890

Volume 67| Part 9| September 2011| Page o2461

doi:10.1107/S1600536811034131

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tert-Butylaminium 2-carboxy-4,5-dichlorobenzoate

Graham Smith ^a ^* and Urs D. Wermuth ^a

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

(Received 18 August 2011; accepted 20 August 2011; online 27 August 2011)

In the structure of the title anhydrous salt, C₄H₁₂N⁺·C₈H₃Cl₂O₄⁻, the 4,5-dichlorophthalate monoanions have the common `planar' conformation with the carboxyl groups close to coplanar with the benzene ring and with a short intramolecular carboxylic acid O—H⋯O hydrogen bond. In the crystal, a two-dimensional sheet structure is formed through aminium N—H⋯O_carboxyl hydrogen-bonding associations.

Related literature

For structures of 1:1 salts of 4,5-dichlorophthalic acid with acyclic aliphatic amines, see: Mattes & Dorau (1986 ); Bozkurt et al. (2006 ); Smith & Wermuth (2010a ,b ,c ).

Experimental

Crystal data

C₄H₁₂N⁺·C₈H₃Cl₂O₄⁻
M_r = 308.15
Monoclinic, P 2₁ /n
a = 6.1778 (2) Å
b = 12.7158 (4) Å
c = 17.7125 (7) Å
β = 96.784 (4)°
V = 1381.68 (8) Å³
Z = 4
Mo Kα radiation
μ = 0.48 mm⁻¹
T = 200 K
0.45 × 0.26 × 0.18 mm

Data collection

Oxford Diffraction Gemini-S CCD-detector diffractometer
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2010 $[Oxford Diffraction (2010). CrysAlis PRO. Oxford Diffraction Ltd, Yarnton, Oxfordshire, England.]$ ) T_min = 0.977, T_max = 0.990
8677 measured reflections
2719 independent reflections
2307 reflections with I > 2σ(I)
R_int = 0.027

Refinement

R[F² > 2σ(F²)] = 0.033
wR(F²) = 0.094
S = 0.90
2719 reflections
188 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.25 e Å⁻³
Δρ_min = −0.21 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1A—H11A⋯O21	0.89 (2)	2.02 (2)	2.883 (2)	164 (2)
N1A—H12A⋯O11ⁱ	0.91 (2)	1.88 (2)	2.784 (2)	174 (2)
N1A—H13A⋯O12ⁱⁱ	0.89 (2)	1.99 (2)	2.861 (2)	167 (2)
O21—H21⋯O12	0.94 (4)	1.47 (4)	2.4021 (19)	173 (4)
Symmetry codes: (i) -x+1, -y+1, -z+2; (ii) x-1, y, z.

Data collection: CrysAlis PRO (Oxford Diffraction, 2010 $[Oxford Diffraction (2010). CrysAlis PRO. Oxford Diffraction Ltd, Yarnton, Oxfordshire, England.]$ ); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SIR92 (Altomare et al., 1994 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ) within WinGX (Farrugia, 1999 ); molecular graphics: PLATON (Spek, 2009 ); software used to prepare material for publication: PLATON.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536811034131/bt5620sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811034131/bt5620Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536811034131/bt5620Isup3.cml

checkCIF report

Comment top

4,5-Dichlorophthalic acid (DCPA) commonly forms 1:1 salts with the acyclic aliphatic amine analogues and with these, low-dimensional hydrogen-bonded structures are usually found, featuring the 'planar' hydrogen phthalate anion e.g with isopropylamine (Smith & Wermuth, 2010a), diisopropylamine (Smith & Wermuth, 2010b), diethylamine, triethylamine and n-butylamine (Smith & Wermuth, 2010c), the ammonium and tetra(nbutyl)ammonium salts (Mattes & Dorau, 1986) and the tetramethylammonium salt (Bozkurt et al., 2006). Our 1:1 stoichiometric reaction of DCPA with t-butylamine also gave a 1:1 salt C₄H₁₂N⁺ C₈H₃Cl₂O₄^-, the title compound and the structure is reported here.

In this structure the common 'planar' DCPA anion is found (Fig. 1) and has the previously described (Smith & Wermuth, 2010c) short intramolecular carboxylic acid O—H···O_carboxy hydrogen bond (Table 1) (torsion angles C1–C2–C21–O22 and C2–C1–C11–O11: 176.59 (18) and 175.26 (17) Å respectively). Other structural features common to this 'planar' monoanion are a lengthening of the C1—C11 and C2—C21 bond lengths [1.522 (2) and 1.528 (3) Å] and distortion of the external bond angles at C1 and C2 [C1—C2—C21, 129.57 (15)° and C2—C1—C11, 128.84 (15)°].

Intermolecular aminium N—H···O(carboxyl) hydrogen bonds (Table 1) link the DCPA monoanions across b as well as down the a axis, forming a two-dimensional sheet structure (Fig. 2).

Related literature top

For structures of 1:1 salts of 4,5-dichlorophthalic acid with acyclic aliphatic amines, see: Mattes & Dorau (1986); Bozkurt et al. (2006); Smith & Wermuth (2010a,b,c).

Experimental top

The title compound was synthesized by heating together for 10 min under reflux, 1 mmol quantities of 4,5-dichlorophthalic acid and t-butylamine in 50 ml of 50% ethanol–water. Partial evaporation of the solvent gave colourless crystalline plates from which a specimen was cleaved for the X-ray analysis..

Computing details top

Data collection: CrysAlis PRO (Oxford Diffraction, 2010); cell refinement: CrysAlis PRO (Oxford Diffraction, 2010); data reduction: CrysAlis PRO (Oxford Diffraction, 2010); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008) within WinGX (Farrugia, 1999); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: PLATON (Spek, 2009).

Figures top

	Fig. 1. Molecular conformation and atom-numbering scheme for the title salt, with the hydrogen bonds shown as a dashed lines. Non-H atoms are shown as 50% probability displacement ellipsoids.
	Fig. 2. A perspective view the two-dimensional sheet structure looking down the sheet, showing hydrogen-bonding associations as dashed lines.

tert-Butylaminium 2-carboxy-4,5-dichlorobenzoate top

Crystal data top

C₄H₁₂N⁺·C₈H₃Cl₂O₄⁻	F(000) = 640
M_r = 308.15	D_x = 1.481 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 4272 reflections
a = 6.1778 (2) Å	θ = 3.3–28.8°
b = 12.7158 (4) Å	µ = 0.48 mm⁻¹
c = 17.7125 (7) Å	T = 200 K
β = 96.784 (4)°	Plate, colourless
V = 1381.68 (8) Å³	0.45 × 0.26 × 0.18 mm
Z = 4

Data collection top

Oxford Diffraction Gemini-S CCD-detector diffractometer	2719 independent reflections
Radiation source: Enhance (Mo) X-ray source	2307 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.027
Detector resolution: 16.077 pixels mm^-1	θ_max = 26.0°, θ_min = 3.4°
ω scans	h = −7→7
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2010)	k = −15→15
T_min = 0.977, T_max = 0.990	l = −21→21
8677 measured reflections

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.033	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.094	H atoms treated by a mixture of independent and constrained refinement
S = 0.90	w = 1/[σ²(F_o²) + (0.0608P)² + 0.4558P] where P = (F_o² + 2F_c²)/3
2719 reflections	(Δ/σ)_max = 0.001
188 parameters	Δρ_max = 0.25 e Å⁻³
0 restraints	Δρ_min = −0.21 e Å⁻³

Crystal data top

C₄H₁₂N⁺·C₈H₃Cl₂O₄⁻	V = 1381.68 (8) Å³
M_r = 308.15	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 6.1778 (2) Å	µ = 0.48 mm⁻¹
b = 12.7158 (4) Å	T = 200 K
c = 17.7125 (7) Å	0.45 × 0.26 × 0.18 mm
β = 96.784 (4)°

Data collection top

Oxford Diffraction Gemini-S CCD-detector diffractometer	2719 independent reflections
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2010)	2307 reflections with I > 2σ(I)
T_min = 0.977, T_max = 0.990	R_int = 0.027
8677 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.033	0 restraints
wR(F²) = 0.094	H atoms treated by a mixture of independent and constrained refinement
S = 0.90	Δρ_max = 0.25 e Å⁻³
2719 reflections	Δρ_min = −0.21 e Å⁻³
188 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

	x	y	z	U_iso*/U_eq
Cl1	0.77566 (7)	−0.08494 (3)	0.92701 (3)	0.0313 (1)
Cl2	0.29591 (7)	−0.09103 (3)	0.84148 (3)	0.0370 (2)
O11	0.8896 (2)	0.29012 (10)	1.01297 (8)	0.0394 (4)
O12	0.6289 (2)	0.40012 (9)	0.97033 (8)	0.0353 (4)
O21	0.2615 (2)	0.39679 (10)	0.90835 (10)	0.0452 (5)
O22	0.0363 (2)	0.28642 (11)	0.84456 (9)	0.0475 (5)
C1	0.5836 (3)	0.21454 (12)	0.93969 (9)	0.0218 (5)
C2	0.3705 (3)	0.21275 (13)	0.90024 (9)	0.0230 (5)
C3	0.2876 (3)	0.11656 (13)	0.87218 (10)	0.0239 (5)
C4	0.4066 (3)	0.02459 (12)	0.87963 (9)	0.0233 (5)
C5	0.6169 (3)	0.02693 (12)	0.91703 (9)	0.0221 (5)
C6	0.7012 (3)	0.12081 (13)	0.94635 (9)	0.0236 (5)
C11	0.7102 (3)	0.30722 (13)	0.97701 (9)	0.0268 (5)
C21	0.2089 (3)	0.30285 (14)	0.88234 (11)	0.0311 (6)
N1A	−0.0938 (3)	0.54459 (13)	0.90362 (9)	0.0257 (5)
C1A	−0.2152 (3)	0.58740 (13)	0.83097 (10)	0.0255 (5)
C2A	−0.0614 (3)	0.66054 (18)	0.79557 (12)	0.0450 (7)
C3A	−0.2819 (3)	0.49408 (16)	0.77986 (11)	0.0380 (6)
C4A	−0.4120 (3)	0.64663 (15)	0.85216 (12)	0.0373 (6)
H3	0.14630	0.11430	0.84740	0.0290*
H6	0.84200	0.12160	0.97160	0.0280*
H21	0.400 (6)	0.399 (3)	0.936 (2)	0.109 (12)*
H11A	0.016 (3)	0.5023 (18)	0.8953 (12)	0.039 (6)*
H12A	−0.036 (4)	0.5995 (18)	0.9325 (13)	0.044 (6)*
H13A	−0.185 (4)	0.5080 (18)	0.9289 (13)	0.042 (6)*
H21A	0.06120	0.62120	0.78220	0.0670*
H22A	−0.01140	0.71450	0.83140	0.0670*
H23A	−0.13660	0.69220	0.75070	0.0670*
H31A	−0.37940	0.44980	0.80390	0.0570*
H32A	−0.15460	0.45460	0.77120	0.0570*
H33A	−0.35380	0.51880	0.73220	0.0570*
H41A	−0.50720	0.59880	0.87410	0.0560*
H42A	−0.48830	0.67810	0.80740	0.0560*
H43A	−0.36510	0.70060	0.88840	0.0560*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cl1	0.0293 (2)	0.0232 (2)	0.0394 (3)	0.0066 (2)	−0.0041 (2)	−0.0007 (2)
Cl2	0.0298 (3)	0.0252 (2)	0.0534 (3)	−0.0039 (2)	−0.0061 (2)	−0.0113 (2)
O11	0.0394 (8)	0.0314 (7)	0.0433 (8)	−0.0070 (6)	−0.0116 (6)	−0.0082 (6)
O12	0.0367 (7)	0.0208 (6)	0.0486 (8)	−0.0044 (5)	0.0059 (6)	−0.0061 (5)
O21	0.0321 (8)	0.0228 (7)	0.0798 (11)	0.0057 (6)	0.0025 (8)	−0.0041 (7)
O22	0.0377 (8)	0.0409 (8)	0.0591 (10)	0.0146 (6)	−0.0148 (7)	−0.0028 (7)
C1	0.0250 (8)	0.0205 (8)	0.0198 (8)	−0.0024 (6)	0.0028 (7)	−0.0010 (6)
C2	0.0228 (8)	0.0233 (8)	0.0231 (8)	0.0017 (6)	0.0031 (7)	0.0010 (6)
C3	0.0180 (8)	0.0274 (8)	0.0257 (8)	−0.0004 (7)	0.0004 (7)	−0.0007 (7)
C4	0.0231 (8)	0.0216 (8)	0.0249 (8)	−0.0033 (6)	0.0012 (7)	−0.0026 (7)
C5	0.0223 (8)	0.0213 (8)	0.0225 (8)	0.0018 (6)	0.0018 (6)	0.0016 (6)
C6	0.0204 (8)	0.0265 (8)	0.0228 (8)	−0.0016 (6)	−0.0020 (7)	−0.0007 (7)
C11	0.0311 (9)	0.0247 (9)	0.0251 (9)	−0.0068 (7)	0.0049 (8)	−0.0032 (7)
C21	0.0316 (10)	0.0258 (9)	0.0361 (10)	0.0067 (7)	0.0053 (8)	0.0027 (8)
N1A	0.0236 (8)	0.0251 (8)	0.0268 (8)	0.0001 (7)	−0.0037 (7)	−0.0033 (6)
C1A	0.0245 (9)	0.0262 (9)	0.0246 (9)	0.0016 (7)	−0.0021 (7)	−0.0001 (7)
C2A	0.0437 (12)	0.0542 (13)	0.0374 (11)	−0.0117 (10)	0.0066 (9)	0.0081 (10)
C3A	0.0385 (11)	0.0404 (11)	0.0315 (10)	0.0050 (9)	−0.0108 (8)	−0.0097 (8)
C4A	0.0328 (10)	0.0329 (10)	0.0451 (11)	0.0079 (8)	0.0004 (9)	0.0001 (9)

Geometric parameters (Å, º) top

Cl1—C5	1.7251 (17)	C4—C5	1.387 (3)
Cl2—C4	1.7253 (16)	C5—C6	1.379 (2)
O11—C11	1.231 (2)	C3—H3	0.9300
O12—C11	1.284 (2)	C6—H6	0.9300
O21—C21	1.307 (2)	C1A—C2A	1.517 (3)
O22—C21	1.208 (2)	C1A—C3A	1.520 (3)
O21—H21	0.94 (4)	C1A—C4A	1.515 (3)
N1A—C1A	1.512 (2)	C2A—H21A	0.9600
N1A—H11A	0.89 (2)	C2A—H22A	0.9600
N1A—H13A	0.89 (2)	C2A—H23A	0.9600
N1A—H12A	0.91 (2)	C3A—H31A	0.9600
C1—C11	1.522 (2)	C3A—H32A	0.9600
C1—C6	1.394 (2)	C3A—H33A	0.9600
C1—C2	1.416 (3)	C4A—H41A	0.9600
C2—C3	1.395 (2)	C4A—H42A	0.9600
C2—C21	1.528 (3)	C4A—H43A	0.9600
C3—C4	1.379 (2)

Cl1···Cl2	3.1661 (7)	O11···C21^v	3.217 (2)
Cl1···O11ⁱ	3.4197 (14)	O11···Cl1ⁱ	3.4197 (14)
Cl1···C3ⁱⁱ	3.6461 (18)	O11···N1A^vi	2.784 (2)
Cl2···Cl1	3.1661 (7)	O12···C21	3.120 (2)
Cl1···H43Aⁱⁱⁱ	2.9200	O12···O12^vi	3.2387 (17)
Cl1···H6ⁱ	2.8300	O12···O21	2.4021 (19)
Cl2···H22A^iv	3.1100	O12···N1A^v	2.861 (2)
O11···O22^v	3.219 (2)	O21···C11	3.109 (2)

C21—O21—H21	113 (2)	C4—C3—H3	119.00
C1A—N1A—H11A	112.8 (14)	C1—C6—H6	119.00
C1A—N1A—H12A	108.9 (14)	C5—C6—H6	119.00
H11A—N1A—H12A	107 (2)	C3A—C1A—C4A	111.52 (15)
H11A—N1A—H13A	108 (2)	N1A—C1A—C2A	107.49 (15)
C1A—N1A—H13A	109.6 (15)	N1A—C1A—C3A	107.35 (14)
H12A—N1A—H13A	110 (2)	N1A—C1A—C4A	107.46 (15)
C2—C1—C11	128.84 (15)	C2A—C1A—C3A	111.81 (16)
C6—C1—C11	112.93 (15)	C2A—C1A—C4A	110.97 (15)
C2—C1—C6	118.24 (15)	C1A—C2A—H21A	109.00
C1—C2—C21	129.57 (15)	C1A—C2A—H22A	109.00
C1—C2—C3	118.09 (15)	C1A—C2A—H23A	109.00
C3—C2—C21	112.35 (16)	H21A—C2A—H22A	109.00
C2—C3—C4	122.71 (17)	H21A—C2A—H23A	109.00
Cl2—C4—C5	120.72 (12)	H22A—C2A—H23A	109.00
Cl2—C4—C3	120.19 (14)	C1A—C3A—H31A	110.00
C3—C4—C5	119.08 (15)	C1A—C3A—H32A	109.00
Cl1—C5—C4	121.35 (12)	C1A—C3A—H33A	109.00
Cl1—C5—C6	119.36 (14)	H31A—C3A—H32A	109.00
C4—C5—C6	119.28 (15)	H31A—C3A—H33A	109.00
C1—C6—C5	122.58 (17)	H32A—C3A—H33A	109.00
O11—C11—C1	118.25 (15)	C1A—C4A—H41A	109.00
O11—C11—O12	121.94 (16)	C1A—C4A—H42A	109.00
O12—C11—C1	119.82 (15)	C1A—C4A—H43A	109.00
O21—C21—C2	118.87 (16)	H41A—C4A—H42A	110.00
O21—C21—O22	121.30 (17)	H41A—C4A—H43A	109.00
O22—C21—C2	119.83 (16)	H42A—C4A—H43A	109.00
C2—C3—H3	119.00

C6—C1—C2—C3	1.9 (2)	C1—C2—C21—O21	−3.2 (3)
C6—C1—C2—C21	−177.99 (17)	C1—C2—C21—O22	176.59 (18)
C11—C1—C2—C3	−178.68 (16)	C3—C2—C21—O21	176.90 (17)
C11—C1—C2—C21	1.4 (3)	C3—C2—C21—O22	−3.3 (2)
C2—C1—C6—C5	−0.9 (2)	C2—C3—C4—Cl2	−178.43 (14)
C11—C1—C6—C5	179.57 (15)	C2—C3—C4—C5	0.5 (3)
C2—C1—C11—O11	175.26 (17)	Cl2—C4—C5—Cl1	−0.1 (2)
C2—C1—C11—O12	−4.8 (3)	Cl2—C4—C5—C6	179.48 (13)
C6—C1—C11—O11	−5.3 (2)	C3—C4—C5—Cl1	−179.02 (13)
C6—C1—C11—O12	174.65 (15)	C3—C4—C5—C6	0.5 (2)
C1—C2—C3—C4	−1.8 (3)	Cl1—C5—C6—C1	179.23 (13)
C21—C2—C3—C4	178.14 (16)	C4—C5—C6—C1	−0.3 (3)

Symmetry codes: (i) −x+2, −y, −z+2; (ii) −x+1, −y, −z+2; (iii) x+1, y−1, z; (iv) x, y−1, z; (v) x+1, y, z; (vi) −x+1, −y+1, −z+2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1A—H11A···O21	0.89 (2)	2.02 (2)	2.883 (2)	164 (2)
N1A—H12A···O11^vi	0.91 (2)	1.88 (2)	2.784 (2)	174 (2)
N1A—H13A···O12^vii	0.89 (2)	1.99 (2)	2.861 (2)	167 (2)
O21—H21···O12	0.94 (4)	1.47 (4)	2.4021 (19)	173 (4)
C3—H3···O22	0.93	2.29	2.671 (2)	104
C6—H6···O11	0.93	2.27	2.657 (2)	104

Symmetry codes: (vi) −x+1, −y+1, −z+2; (vii) x−1, y, z.

Experimental details

Crystal data
Chemical formula	C₄H₁₂N⁺·C₈H₃Cl₂O₄⁻
M_r	308.15
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	200
a, b, c (Å)	6.1778 (2), 12.7158 (4), 17.7125 (7)
β (°)	96.784 (4)
V (Å³)	1381.68 (8)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.48
Crystal size (mm)	0.45 × 0.26 × 0.18

Data collection
Diffractometer	Oxford Diffraction Gemini-S CCD-detector diffractometer
Absorption correction	Multi-scan (CrysAlis PRO; Oxford Diffraction, 2010)
T_min, T_max	0.977, 0.990
No. of measured, independent and observed [I > 2σ(I)] reflections	8677, 2719, 2307
R_int	0.027
(sin θ/λ)_max (Å⁻¹)	0.617

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.033, 0.094, 0.90
No. of reflections	2719
No. of parameters	188
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.25, −0.21

Computer programs: CrysAlis PRO (Oxford Diffraction, 2010), SIR92 (Altomare et al., 1994), SHELXL97 (Sheldrick, 2008) within WinGX (Farrugia, 1999), PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1A—H11A···O21	0.89 (2)	2.02 (2)	2.883 (2)	164 (2)
N1A—H12A···O11ⁱ	0.91 (2)	1.88 (2)	2.784 (2)	174 (2)
N1A—H13A···O12ⁱⁱ	0.89 (2)	1.99 (2)	2.861 (2)	167 (2)
O21—H21···O12	0.94 (4)	1.47 (4)	2.4021 (19)	173 (4)

Symmetry codes: (i) −x+1, −y+1, −z+2; (ii) x−1, y, z.

Acknowledgements

The authors acknowledge financial support from the Australian Research Council and the Faculty of Science and Technology and the University Library, Queensland University of Technology.

References

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