Tetra­ethyl­ammonium l-tartarate dihydrate

Rahman, M.B.A.; Jumbri, K.; Sirat, K.; Kia, R.; Fun, H.-K.

doi:10.1107/S1600536808036969

organic compounds

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ISSN: 2056-9890

Volume 64| Part 12| December 2008| Page o2343

doi:10.1107/S1600536808036969

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Tetraethylammonium L-tartarate dihydrate

Mohd Basyaruddin Abdul Rahman,^a ‡ Khairulazhar Jumbri,^a Kamaliah Sirat,^a Reza Kia ^b and Hoong-Kun Fun ^b ^*

^aDepartment of Chemistry, Faculty of Science, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia, and ^bX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia
^*Correspondence e-mail: hkfun@usm.my

(Received 3 November 2008; accepted 10 November 2008; online 13 November 2008)

In the crystal structure of the title compound, C₈H₂₀N⁺·C₄H₅O₆⁻·2H₂O, the ions and water molecules are linked via O—H⋯O and C—H⋯O hydrogen bonds, forming a two-dimensional network parallel to (001).

Related literature

For hydrogen-bond motifs, see: Bernstein et al. (1995 ). For related structures, see: Allen et al. (2006 ); Jiang et al. (2008 ); Mei et al. (2002 ).

Experimental

Crystal data

C₈H₂₀N⁺·C₄H₅O₆⁻·2H₂O
M_r = 315.36
Monoclinic, P 2₁
a = 7.4074 (1) Å
b = 13.8989 (2) Å
c = 8.0546 (1) Å
β = 106.553 (1)°
V = 794.89 (2) Å³
Z = 2
Mo Kα radiation
μ = 0.11 mm⁻¹
T = 100.0 (1) K
0.47 × 0.45 × 0.17 mm

Data collection

Bruker SMART APEXII CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2005 ) T_min = 0.861, T_max = 0.981
10518 measured reflections
3579 independent reflections
3240 reflections with I > 2σ(I)
R_int = 0.031

Refinement

R[F² > 2σ(F²)] = 0.037
wR(F²) = 0.092
S = 1.05
3579 reflections
218 parameters
1 restraint
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.29 e Å⁻³
Δρ_min = −0.23 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O2—H1O2⋯O5ⁱ	1.00 (2)	1.52 (2)	2.5108 (13)	173 (2)
O3—H1O3⋯O1Wⁱⁱ	0.91 (2)	1.85 (2)	2.7191 (14)	162 (2)
O4—H1O4⋯O2Wⁱⁱⁱ	0.84 (2)	2.18 (2)	2.9780 (16)	160 (2)
O1W—H1W1⋯O2^iv	0.82 (2)	2.56 (2)	3.0668 (14)	122 (2)
O1W—H1W1⋯O2W^v	0.82 (2)	2.57 (2)	3.2155 (16)	137 (2)
O1W—H2W1⋯O6ⁱⁱⁱ	0.88 (3)	2.00 (3)	2.8672 (15)	171 (2)
O2W—H2W2⋯O1^vi	0.84 (2)	2.40 (2)	3.0082 (14)	129 (2)
C5—H5A⋯O3^vii	0.97	2.56	3.4344 (15)	151
C8—H8B⋯O4	0.96	2.38	3.3447 (16)	178
C10—H10B⋯O3^vii	0.96	2.47	3.4195 (16)	168
C11—H11A⋯O4	0.97	2.50	3.2693 (15)	136
Symmetry codes: (i) $[-x+2, y-{\script{1\over 2}}, -z]$ ; (ii) x, y, z-1; (iii) $[-x+1, y-{\script{1\over 2}}, -z+1]$ ; (iv) x-1, y, z+1; (v) $[-x+1, y-{\script{1\over 2}}, -z+2]$ ; (vi) x, y+1, z+1; (vii) $[-x+1, y-{\script{1\over 2}}, -z]$ .

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2003 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808036969/ci2709sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808036969/ci2709Isup2.hkl

checkCIF report

Comment top

The crystal structures of chiral complexes of the plant acid (L-tartaric acid) with tetraethylammonium have been investigated in our laboratory in order to understand the nature of intramolecular and intermolecular interactions. The title compound was obtained by neutralization method at room temperature. Some other related compounds containing the same cation have been previously reported (Jiang et al., 2008; Allen et al., 2006). The crystal structure of bis(tetraethylammonium) tartrate bis(thiourea) dihydrate has also been reported (Mei et al., 2002).

The asymmetric unit of the title compound (Fig. 1) contains a tartarate anion, a tetraethylammonium cation and two water molecules of crystallization. Two intermolecular C—H···O hydrogen bonds involving O4 as a bifurcated acceptor link anion and cation in the asymmetric unit to form a seven-membered ring, with R¹₂(7) ring motif (Bernstein et al., 1995). In the crystal structure, the ionic units and water molecules are linked via O—H···O and C—H···O hydrogen bonds (Table 1) forming a two-dimensional network parallel to the (001) [Fig. 2].

Related literature top

For hydrogen-bond motifs, see: Bernstein et al. (1995). For related structures, see: Allen et al. (2006); Jiang et al. (2008); Mei et al. (2002).

Experimental top

L-Tartaric acid (7.504 g, 0.05 mol) was first dissolved in 20 ml of distilled water in a 50 ml beaker. An aqueous solution (20% in water) of tetraethylammonium hydroxide (36.59 ml, 0.05 mol) was added slowly into an aqueous solution of L-tartaric acid and the mixture was stirred with a magnetic stirrer for 2 h at room temperature. A white solid product was obtained after being dried at 343 K under vacuum for 2 d. The product was dissolved in methanol and then covered by aluminium foil to allow slow evaporation at room temperature. Clear crystalline solid was obtained after 3 d. Decomposition temperature range (471.35–472.6 K). Analysis calculated (%): C 51.60, H 9.02, N 5.01%; found: C 50.53, H 9.09, N 3.28%.

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2003).

Figures top

	Fig. 1. The molecular structure of the title compound, showing 50% probability displacement ellipsoids and the atomic numbering. Hydrogen bonds are shown as dashed lines.
	Fig. 2. The crystal packing of the title compound, viewd down the c axis. Hydrogen bonds are shown as dashed lines.

Tetraethylammonium L-tartarate dihydrate top

Crystal data top

C₈H₂₀N⁺·C₄H₅O₆⁻·2H₂O	F(000) = 344
M_r = 315.36	D_x = 1.318 Mg m⁻³
Monoclinic, P2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2yb	Cell parameters from 4555 reflections
a = 7.4074 (1) Å	θ = 2.6–33.5°
b = 13.8989 (2) Å	µ = 0.11 mm⁻¹
c = 8.0546 (1) Å	T = 100 K
β = 106.553 (1)°	Block, colourless
V = 794.89 (2) Å³	0.47 × 0.45 × 0.17 mm
Z = 2

Data collection top

Bruker SMART APEXII CCD area-detector diffractometer	3579 independent reflections
Radiation source: fine-focus sealed tube	3240 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.031
ϕ and ω scans	θ_max = 35.0°, θ_min = 2.6°
Absorption correction: multi-scan (SADABS; Bruker, 2005)	h = −9→11
T_min = 0.861, T_max = 0.981	k = −22→17
10518 measured reflections	l = −12→12

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)] = 0.037	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.092	H atoms treated by a mixture of independent and constrained refinement
S = 1.05	w = 1/[σ²(F_o²) + (0.0494P)² + 0.0426P] where P = (F_o² + 2F_c²)/3
3579 reflections	(Δ/σ)_max = 0.001
218 parameters	Δρ_max = 0.29 e Å⁻³
1 restraint	Δρ_min = −0.23 e Å⁻³

Crystal data top

C₈H₂₀N⁺·C₄H₅O₆⁻·2H₂O	V = 794.89 (2) Å³
M_r = 315.36	Z = 2
Monoclinic, P2₁	Mo Kα radiation
a = 7.4074 (1) Å	µ = 0.11 mm⁻¹
b = 13.8989 (2) Å	T = 100 K
c = 8.0546 (1) Å	0.47 × 0.45 × 0.17 mm
β = 106.553 (1)°

Data collection top

Bruker SMART APEXII CCD area-detector diffractometer	3579 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2005)	3240 reflections with I > 2σ(I)
T_min = 0.861, T_max = 0.981	R_int = 0.031
10518 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.037	1 restraint
wR(F²) = 0.092	H atoms treated by a mixture of independent and constrained refinement
S = 1.05	Δρ_max = 0.29 e Å⁻³
3579 reflections	Δρ_min = −0.23 e Å⁻³
218 parameters

Special details top

Experimental. The low-temperature data was collected with the Oxford Cyrosystem Cobra low-temperature attachment.

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

	x	y	z	U_iso*/U_eq
O1	0.71436 (14)	0.19227 (7)	−0.03566 (13)	0.01818 (18)
O2	1.02013 (14)	0.23261 (7)	0.04449 (14)	0.0201 (2)
O3	0.61932 (14)	0.36818 (7)	−0.18764 (12)	0.01677 (18)
O4	0.68458 (16)	0.39108 (7)	0.17930 (13)	0.0190 (2)
C1	0.83853 (18)	0.25107 (9)	−0.01824 (15)	0.0138 (2)
C2	0.79871 (18)	0.35668 (9)	−0.06869 (15)	0.0134 (2)
H2A	0.8929	0.3785	−0.1246	0.016*
C3	0.81928 (18)	0.41837 (9)	0.09447 (16)	0.0144 (2)
H3A	0.9446	0.4064	0.1739	0.017*
C4	0.80699 (19)	0.52553 (9)	0.04614 (16)	0.0156 (2)
N1	0.61784 (16)	0.13577 (8)	0.44527 (13)	0.01415 (19)
C5	0.68066 (19)	0.05680 (10)	0.34333 (17)	0.0169 (2)
H5A	0.5698	0.0232	0.2745	0.020*
H5B	0.7406	0.0866	0.2638	0.020*
C6	0.8153 (2)	−0.01643 (11)	0.4516 (2)	0.0249 (3)
H6A	0.8474	−0.0632	0.3769	0.037*
H6B	0.7563	−0.0481	0.5285	0.037*
H6C	0.9275	0.0156	0.5181	0.037*
C7	0.78506 (19)	0.18803 (10)	0.56438 (16)	0.0174 (2)
H7A	0.7381	0.2382	0.6249	0.021*
H7B	0.8550	0.1428	0.6507	0.021*
C8	0.9195 (2)	0.23319 (12)	0.47596 (19)	0.0227 (3)
H8A	1.0203	0.2644	0.5609	0.034*
H8B	0.8532	0.2797	0.3926	0.034*
H8C	0.9703	0.1841	0.4183	0.034*
C9	0.50734 (19)	0.09482 (11)	0.56176 (16)	0.0186 (2)
H9A	0.5880	0.0505	0.6428	0.022*
H9B	0.4763	0.1471	0.6286	0.022*
C10	0.3270 (2)	0.04279 (11)	0.46895 (19)	0.0218 (3)
H10A	0.2674	0.0194	0.5523	0.033*
H10B	0.3558	−0.0104	0.4047	0.033*
H10C	0.2437	0.0864	0.3910	0.033*
C11	0.49727 (18)	0.20335 (10)	0.31067 (15)	0.0157 (2)
H11A	0.5737	0.2288	0.2411	0.019*
H11B	0.3959	0.1665	0.2344	0.019*
C12	0.4121 (2)	0.28706 (11)	0.38285 (18)	0.0205 (3)
H12A	0.3389	0.3259	0.2891	0.031*
H12B	0.5110	0.3253	0.4562	0.031*
H12C	0.3325	0.2630	0.4489	0.031*
O1W	0.30848 (16)	0.27561 (10)	0.84652 (15)	0.0243 (2)
O2W	0.69834 (18)	0.97603 (9)	0.95574 (16)	0.0252 (2)
O5	0.93673 (14)	0.55475 (7)	−0.01728 (15)	0.0218 (2)
O6	0.67739 (15)	0.57466 (8)	0.07043 (14)	0.0226 (2)
H1O2	1.043 (4)	0.161 (2)	0.045 (3)	0.045 (7)*
H1O3	0.534 (3)	0.3304 (19)	−0.159 (3)	0.036 (6)*
H1O4	0.590 (3)	0.422 (2)	0.122 (3)	0.033 (6)*
H1W1	0.260 (4)	0.306 (2)	0.911 (4)	0.055 (8)*
H2W1	0.316 (4)	0.216 (2)	0.884 (3)	0.043 (7)*
H1W2	0.818 (4)	0.9985 (19)	0.980 (3)	0.037 (6)*
H2W2	0.630 (4)	1.025 (2)	0.962 (3)	0.039 (6)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0174 (4)	0.0115 (4)	0.0261 (4)	−0.0015 (3)	0.0070 (4)	0.0010 (4)
O2	0.0150 (4)	0.0121 (4)	0.0307 (5)	0.0009 (4)	0.0027 (4)	−0.0024 (4)
O3	0.0174 (4)	0.0135 (4)	0.0167 (4)	−0.0013 (3)	0.0006 (3)	0.0020 (3)
O4	0.0242 (5)	0.0155 (4)	0.0191 (4)	0.0013 (4)	0.0091 (4)	0.0022 (3)
C1	0.0164 (5)	0.0107 (5)	0.0146 (4)	0.0011 (4)	0.0050 (4)	−0.0005 (4)
C2	0.0151 (5)	0.0095 (5)	0.0156 (4)	−0.0007 (4)	0.0040 (4)	0.0005 (4)
C3	0.0161 (5)	0.0096 (5)	0.0162 (5)	0.0001 (4)	0.0024 (4)	−0.0005 (4)
C4	0.0164 (5)	0.0104 (5)	0.0180 (5)	−0.0001 (4)	0.0013 (4)	−0.0010 (4)
N1	0.0153 (5)	0.0138 (5)	0.0131 (4)	−0.0007 (4)	0.0037 (3)	0.0003 (3)
C5	0.0185 (5)	0.0134 (5)	0.0191 (5)	−0.0001 (5)	0.0057 (4)	−0.0026 (4)
C6	0.0232 (7)	0.0160 (6)	0.0349 (7)	0.0027 (5)	0.0071 (6)	0.0032 (5)
C7	0.0168 (5)	0.0175 (6)	0.0156 (5)	−0.0016 (5)	0.0007 (4)	−0.0013 (4)
C8	0.0191 (6)	0.0217 (7)	0.0256 (6)	−0.0052 (5)	0.0036 (5)	0.0012 (5)
C9	0.0200 (6)	0.0209 (6)	0.0162 (5)	−0.0018 (5)	0.0073 (4)	0.0025 (4)
C10	0.0196 (6)	0.0221 (7)	0.0254 (6)	−0.0029 (5)	0.0089 (5)	0.0024 (5)
C11	0.0171 (5)	0.0147 (5)	0.0140 (4)	0.0012 (4)	0.0024 (4)	0.0012 (4)
C12	0.0213 (6)	0.0161 (6)	0.0235 (6)	0.0025 (5)	0.0055 (5)	−0.0020 (5)
O1W	0.0200 (5)	0.0272 (6)	0.0262 (5)	−0.0003 (4)	0.0076 (4)	0.0019 (4)
O2W	0.0250 (6)	0.0191 (5)	0.0321 (5)	−0.0048 (4)	0.0094 (4)	−0.0044 (4)
O5	0.0187 (4)	0.0118 (4)	0.0361 (5)	−0.0022 (4)	0.0096 (4)	0.0006 (4)
O6	0.0245 (5)	0.0164 (5)	0.0286 (5)	0.0071 (4)	0.0102 (4)	0.0021 (4)

Geometric parameters (Å, º) top

O1—C1	1.2084 (16)	C6—H6C	0.96
O2—C1	1.3203 (15)	C7—C8	1.516 (2)
O2—H1O2	1.01 (3)	C7—H7A	0.97
O3—C2	1.4085 (16)	C7—H7B	0.97
O3—H1O3	0.90 (3)	C8—H8A	0.96
O4—C3	1.4124 (17)	C8—H8B	0.96
O4—H1O4	0.84 (3)	C8—H8C	0.96
C1—C2	1.5292 (17)	C9—C10	1.516 (2)
C2—C3	1.5400 (17)	C9—H9A	0.97
C2—H2A	0.98	C9—H9B	0.97
C3—C4	1.5356 (18)	C10—H10A	0.96
C3—H3A	0.98	C10—H10B	0.96
C4—O6	1.2382 (17)	C10—H10C	0.96
C4—O5	1.2763 (17)	C11—C12	1.516 (2)
N1—C11	1.5178 (16)	C11—H11A	0.97
N1—C7	1.5183 (17)	C11—H11B	0.97
N1—C9	1.5205 (16)	C12—H12A	0.96
N1—C5	1.5209 (17)	C12—H12B	0.96
C5—C6	1.515 (2)	C12—H12C	0.96
C5—H5A	0.97	O1W—H1W1	0.83 (3)
C5—H5B	0.97	O1W—H2W1	0.88 (3)
C6—H6A	0.96	O2W—H1W2	0.91 (3)
C6—H6B	0.96	O2W—H2W2	0.85 (3)

C1—O2—H1O2	110.3 (15)	C8—C7—N1	115.36 (10)
C2—O3—H1O3	110.7 (16)	C8—C7—H7A	108.4
C3—O4—H1O4	101.3 (17)	N1—C7—H7A	108.4
O1—C1—O2	124.88 (12)	C8—C7—H7B	108.4
O1—C1—C2	122.38 (11)	N1—C7—H7B	108.4
O2—C1—C2	112.74 (11)	H7A—C7—H7B	107.5
O3—C2—C1	111.28 (10)	C7—C8—H8A	109.5
O3—C2—C3	111.23 (10)	C7—C8—H8B	109.5
C1—C2—C3	110.06 (10)	H8A—C8—H8B	109.5
O3—C2—H2A	108.0	C7—C8—H8C	109.5
C1—C2—H2A	108.0	H8A—C8—H8C	109.5
C3—C2—H2A	108.0	H8B—C8—H8C	109.5
O4—C3—C4	112.59 (11)	C10—C9—N1	115.34 (10)
O4—C3—C2	110.58 (10)	C10—C9—H9A	108.4
C4—C3—C2	109.84 (10)	N1—C9—H9A	108.4
O4—C3—H3A	107.9	C10—C9—H9B	108.4
C4—C3—H3A	107.9	N1—C9—H9B	108.4
C2—C3—H3A	107.9	H9A—C9—H9B	107.5
O6—C4—O5	126.43 (13)	C9—C10—H10A	109.5
O6—C4—C3	119.17 (12)	C9—C10—H10B	109.5
O5—C4—C3	114.40 (11)	H10A—C10—H10B	109.5
C11—N1—C7	111.31 (10)	C9—C10—H10C	109.5
C11—N1—C9	111.21 (10)	H10A—C10—H10C	109.5
C7—N1—C9	105.96 (9)	H10B—C10—H10C	109.5
C11—N1—C5	105.62 (9)	C12—C11—N1	115.18 (10)
C7—N1—C5	111.49 (10)	C12—C11—H11A	108.5
C9—N1—C5	111.36 (10)	N1—C11—H11A	108.5
C6—C5—N1	115.24 (11)	C12—C11—H11B	108.5
C6—C5—H5A	108.5	N1—C11—H11B	108.5
N1—C5—H5A	108.5	H11A—C11—H11B	107.5
C6—C5—H5B	108.5	C11—C12—H12A	109.5
N1—C5—H5B	108.5	C11—C12—H12B	109.5
H5A—C5—H5B	107.5	H12A—C12—H12B	109.5
C5—C6—H6A	109.5	C11—C12—H12C	109.5
C5—C6—H6B	109.5	H12A—C12—H12C	109.5
H6A—C6—H6B	109.5	H12B—C12—H12C	109.5
C5—C6—H6C	109.5	H1W1—O1W—H2W1	106 (3)
H6A—C6—H6C	109.5	H1W2—O2W—H2W2	106 (2)
H6B—C6—H6C	109.5

O1—C1—C2—O3	−20.73 (16)	C11—N1—C5—C6	175.99 (11)
O2—C1—C2—O3	159.12 (10)	C7—N1—C5—C6	54.95 (15)
O1—C1—C2—C3	103.04 (13)	C9—N1—C5—C6	−63.16 (15)
O2—C1—C2—C3	−77.11 (13)	C11—N1—C7—C8	−60.40 (15)
O3—C2—C3—O4	60.68 (13)	C9—N1—C7—C8	178.57 (12)
C1—C2—C3—O4	−63.12 (13)	C5—N1—C7—C8	57.25 (15)
O3—C2—C3—C4	−64.19 (13)	C11—N1—C9—C10	56.22 (15)
C1—C2—C3—C4	172.01 (10)	C7—N1—C9—C10	177.31 (12)
O4—C3—C4—O6	−5.84 (16)	C5—N1—C9—C10	−61.29 (15)
C2—C3—C4—O6	117.86 (13)	C7—N1—C11—C12	−60.88 (14)
O4—C3—C4—O5	174.27 (11)	C9—N1—C11—C12	57.02 (14)
C2—C3—C4—O5	−62.03 (14)	C5—N1—C11—C12	177.97 (12)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O2—H1O2···O5ⁱ	1.00 (2)	1.52 (2)	2.5108 (13)	173 (2)
O3—H1O3···O1Wⁱⁱ	0.91 (2)	1.85 (2)	2.7191 (14)	162 (2)
O4—H1O4···O2Wⁱⁱⁱ	0.84 (2)	2.18 (2)	2.9780 (16)	160 (2)
O1W—H1W1···O2^iv	0.82 (2)	2.56 (2)	3.0668 (14)	122 (2)
O1W—H1W1···O2W^v	0.82 (2)	2.57 (2)	3.2155 (16)	137 (2)
O1W—H2W1···O6ⁱⁱⁱ	0.88 (3)	2.00 (3)	2.8672 (15)	171 (2)
O2W—H2W2···O1^vi	0.84 (2)	2.40 (2)	3.0082 (14)	129 (2)
C5—H5A···O3^vii	0.97	2.56	3.4344 (15)	151
C8—H8B···O4	0.96	2.38	3.3447 (16)	178
C10—H10B···O3^vii	0.96	2.47	3.4195 (16)	168
C11—H11A···O4	0.97	2.50	3.2693 (15)	136

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

Experimental details

Crystal data
Chemical formula	C₈H₂₀N⁺·C₄H₅O₆⁻·2H₂O
M_r	315.36
Crystal system, space group	Monoclinic, P2₁
Temperature (K)	100
a, b, c (Å)	7.4074 (1), 13.8989 (2), 8.0546 (1)
β (°)	106.553 (1)
V (Å³)	794.89 (2)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.11
Crystal size (mm)	0.47 × 0.45 × 0.17

Data collection
Diffractometer	Bruker SMART APEXII CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2005)
T_min, T_max	0.861, 0.981
No. of measured, independent and observed [I > 2σ(I)] reflections	10518, 3579, 3240
R_int	0.031
(sin θ/λ)_max (Å⁻¹)	0.807

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.037, 0.092, 1.05
No. of reflections	3579
No. of parameters	218
No. of restraints	1
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.29, −0.23

Computer programs: APEX2 (Bruker, 2005), SAINT (Bruker, 2005), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2003).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O2—H1O2···O5ⁱ	1.00 (2)	1.52 (2)	2.5108 (13)	173 (2)
O3—H1O3···O1Wⁱⁱ	0.91 (2)	1.85 (2)	2.7191 (14)	162 (2)
O4—H1O4···O2Wⁱⁱⁱ	0.84 (2)	2.18 (2)	2.9780 (16)	160 (2)
O1W—H1W1···O2^iv	0.82 (2)	2.56 (2)	3.0668 (14)	122 (2)
O1W—H1W1···O2W^v	0.82 (2)	2.57 (2)	3.2155 (16)	137 (2)
O1W—H2W1···O6ⁱⁱⁱ	0.88 (3)	2.00 (3)	2.8672 (15)	171 (2)
O2W—H2W2···O1^vi	0.84 (2)	2.40 (2)	3.0082 (14)	129 (2)
C5—H5A···O3^vii	0.97	2.56	3.4344 (15)	151
C8—H8B···O4	0.96	2.38	3.3447 (16)	178
C10—H10B···O3^vii	0.96	2.47	3.4195 (16)	168
C11—H11A···O4	0.97	2.50	3.2693 (15)	136

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

Footnotes

‡Additional correspondance author: Laboratory of Industrial Biotechnology Institute of Bioscience, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia; e-mail: basya@science.upm.edu.my.

Acknowledgements

MBAR, KJ and KS thank the Ministry of Higher Education of Malaysia for the research grant 05-10-07-377FR (Fundamental Research Grant Scheme-FRGS). HKF and RK thank the Malaysian Government and Universiti Sains Malaysia for the Science Fund (grant No. 305/PFIZIK/613312). RK thanks Universiti Sains Malaysia for the award of a post-doctoral research fellowship.

References

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