Bis(imidazolium) galacta-rate dihydrate.

In the structure of the title salt, 2C(3)H(5)N(2) (+)·C(6)H(8)O(8) (2-)·2H(2)O, the galacta-rate dianions have crystallographic inversion symmetry and together with the water mol-ecules of solvation form hydrogen-bonded sheet substructures which extend along (110). The imidazolium cations link these sheets peripherally down c through carboxyl-ate O-H-N and N'-H⋯O(hy-droxy) bridges, giving a three-dimensional framework structure.

Related literature

For mention of mucic acid in the Merck Index, see: O’Neil (2001 ▶). For the structures of imidazolium hydrogen salts of aliphatic dicarb­oxy­lic acids, see: James & Matsushima (1976 ▶); MacDonald et al. (2001 ▶); Aakeröy & Hitchcock (1993 ▶); Fuller et al. (1995 ▶); Fukunaga & Ishida (2003 ▶); Trivedi et al. (2003 ▶). For the structures of galacta­ric acid, ammonium H galacta­rate, diammonium galacta­rate and copper(II) galacta­rate dihydrate, see: Jeffrey & Wood (1982 ▶), Bontchev & Moore (2005 ▶), Benetollo et al. (1993 ▶) and Ferrier et al. (1998 ▶) respectively. For graph-set analysis, see: Etter et al. (1990 ▶).

Experimental

Crystal data

2C3H5N2 +·C6H8O8 2−·2H2O

M = 382.34

Triclinic,

a = 6.9184 (4) Å

b = 7.1336 (4) Å

c = 9.3652 (5) Å

α = 92.000 (5)°

β = 100.559 (5)°

γ = 109.835 (6)°

V = 425.06 (5) Å3

Z = 1

Mo Kα radiation

μ = 0.13 mm−1

T = 200 K

0.45 × 0.45 × 0.30 mm

Data collection

Oxford Diffraction Gemini-S CCD-detector diffractometer

Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2010 ▶) T min = 0.965, T max = 0.980

4949 measured reflections

1657 independent reflections

1431 reflections with I > 2σ(I)

R int = 0.019

Refinement

R[F 2 > 2σ(F 2)] = 0.030

wR(F 2) = 0.082

S = 1.13

1657 reflections

142 parameters

H atoms treated by a mixture of independent and constrained refinement

Δρmax = 0.30 e Å−3

Δρmin = −0.20 e Å−3

Data collection: CrysAlis PRO (Oxford Diffraction, 2010 ▶); 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.

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810033532/ng5021sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810033532/ng5021Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

2C3H5N2+·C6H8O82−·2H2O	Z = 1
Mr = 382.34	F(000) = 202
Triclinic, P1	Dx = 1.494 Mg m−3
Hall symbol: -P 1	Melting point: 435 K
a = 6.9184 (4) Å	Mo Kα radiation, λ = 0.71073 Å
b = 7.1336 (4) Å	Cell parameters from 3387 reflections
c = 9.3652 (5) Å	θ = 3.5–28.7°
α = 92.000 (5)°	µ = 0.13 mm−1
β = 100.559 (5)°	T = 200 K
γ = 109.835 (6)°	Plate, colourless
V = 425.06 (5) Å3	0.45 × 0.45 × 0.30 mm

Oxford Diffraction Gemini-S CCD-detector diffractometer	1657 independent reflections
Radiation source: Enhance (Mo) X-ray source	1431 reflections with I > 2σ(I)
graphite	Rint = 0.019
ω scans	θmax = 26.0°, θmin = 3.5°
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2010)	h = −8→8
Tmin = 0.965, Tmax = 0.980	k = −8→8
4949 measured reflections	l = −11→11

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)] = 0.030	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.082	H atoms treated by a mixture of independent and constrained refinement
S = 1.13	w = 1/[σ2(Fo2) + (0.0444P)2 + 0.0516P] where P = (Fo2 + 2Fc2)/3
1657 reflections	(Δ/σ)max = 0.001
142 parameters	Δρmax = 0.30 e Å−3
0 restraints	Δρmin = −0.20 e Å−3

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.

	x	y	z	Uiso*/Ueq
O11	0.18384 (15)	−0.07229 (13)	0.80626 (9)	0.0234 (3)
O12	0.26773 (14)	−0.02982 (13)	1.04961 (9)	0.0207 (3)
O21	0.19607 (14)	0.29951 (14)	0.78260 (9)	0.0203 (3)
O31	0.62559 (14)	0.35914 (13)	0.90945 (10)	0.0197 (3)
C1	0.23436 (18)	0.03283 (17)	0.92558 (13)	0.0154 (3)
C2	0.25848 (18)	0.25478 (17)	0.92684 (12)	0.0151 (3)
C3	0.48566 (18)	0.38863 (17)	0.99549 (13)	0.0153 (3)
N11	0.34766 (19)	0.22454 (18)	0.54570 (12)	0.0261 (4)
N31	0.35478 (19)	0.13600 (18)	0.32587 (12)	0.0265 (4)
C21	0.2302 (2)	0.1404 (2)	0.41585 (14)	0.0269 (4)
C41	0.5588 (2)	0.2202 (2)	0.40018 (15)	0.0302 (5)
C51	0.5544 (2)	0.2764 (2)	0.53780 (15)	0.0285 (4)
O1W	−0.02769 (16)	0.53271 (15)	0.78655 (11)	0.0244 (3)
H22	0.118 (3)	0.373 (3)	0.7852 (19)	0.046 (5)*
H2	0.16380	0.28050	0.98780	0.0180*
H3	0.52450	0.35200	1.09610	0.0180*
H32	0.657 (3)	0.260 (3)	0.9315 (18)	0.040 (5)*
H11	0.301 (3)	0.245 (3)	0.625 (2)	0.048 (5)*
H21	0.08100	0.09150	0.39160	0.0320*
H31	0.318 (3)	0.084 (3)	0.233 (2)	0.044 (5)*
H41	0.68070	0.23610	0.36180	0.0360*
H51	0.67240	0.34010	0.61480	0.0340*
H11W	0.043 (3)	0.660 (4)	0.803 (2)	0.057 (6)*
H12W	−0.127 (4)	0.500 (3)	0.835 (2)	0.059 (6)*

	U11	U22	U33	U12	U13	U23
O11	0.0320 (5)	0.0168 (5)	0.0185 (5)	0.0058 (4)	0.0047 (4)	−0.0032 (4)
O12	0.0290 (5)	0.0158 (5)	0.0174 (4)	0.0077 (4)	0.0056 (4)	0.0024 (3)
O21	0.0257 (5)	0.0230 (5)	0.0157 (5)	0.0135 (4)	0.0032 (4)	0.0023 (4)
O31	0.0214 (5)	0.0149 (5)	0.0265 (5)	0.0079 (4)	0.0113 (4)	0.0032 (4)
C1	0.0129 (6)	0.0148 (6)	0.0174 (6)	0.0026 (5)	0.0051 (4)	0.0001 (5)
C2	0.0185 (6)	0.0143 (6)	0.0132 (6)	0.0058 (5)	0.0049 (5)	0.0009 (5)
C3	0.0185 (6)	0.0136 (6)	0.0144 (6)	0.0052 (5)	0.0054 (5)	0.0017 (5)
N11	0.0347 (7)	0.0308 (7)	0.0175 (6)	0.0160 (5)	0.0084 (5)	0.0031 (5)
N31	0.0379 (7)	0.0260 (6)	0.0152 (6)	0.0116 (5)	0.0044 (5)	0.0010 (5)
C21	0.0273 (7)	0.0304 (8)	0.0230 (7)	0.0104 (6)	0.0043 (6)	0.0070 (6)
C41	0.0311 (8)	0.0336 (8)	0.0301 (8)	0.0134 (6)	0.0120 (6)	0.0064 (6)
C51	0.0286 (7)	0.0294 (8)	0.0241 (7)	0.0085 (6)	0.0007 (6)	0.0004 (6)
O1W	0.0231 (5)	0.0180 (5)	0.0325 (6)	0.0063 (4)	0.0095 (4)	−0.0005 (4)

O11—C1	1.2465 (15)	N11—H11	0.89 (2)
O12—C1	1.2690 (15)	N31—H31	0.890 (18)
O21—C2	1.4223 (14)	C1—C2	1.5341 (16)
O31—C3	1.4293 (16)	C2—C3	1.5375 (18)
O21—H22	0.87 (2)	C3—C3i	1.5303 (16)
O31—H32	0.83 (2)	C2—H2	1.0000
O1W—H11W	0.87 (3)	C3—H3	1.0000
O1W—H12W	0.86 (3)	C41—C51	1.345 (2)
N11—C21	1.3249 (17)	C21—H21	0.9500
N11—C51	1.367 (2)	C41—H41	0.9500
N31—C21	1.3178 (19)	C51—H51	0.9500
N31—C41	1.369 (2)
C2—O21—H22	108.6 (11)	O31—C3—C3i	107.52 (10)
C3—O31—H32	110.6 (13)	O21—C2—H2	108.00
H11W—O1W—H12W	111 (2)	C3—C2—H2	108.00
C21—N11—C51	108.65 (12)	C1—C2—H2	108.00
C21—N31—C41	108.66 (11)	O31—C3—H3	109.00
C51—N11—H11	125.3 (14)	C2—C3—H3	109.00
C21—N11—H11	126.1 (14)	C3i—C3—H3	109.00
C41—N31—H31	123.6 (14)	N11—C21—N31	108.63 (13)
C21—N31—H31	127.7 (14)	N31—C41—C51	107.15 (13)
O12—C1—C2	116.02 (10)	N11—C51—C41	106.92 (12)
O11—C1—O12	124.82 (11)	N31—C21—H21	126.00
O11—C1—C2	119.16 (10)	N11—C21—H21	126.00
O21—C2—C3	111.32 (10)	N31—C41—H41	126.00
O21—C2—C1	110.05 (9)	C51—C41—H41	126.00
C1—C2—C3	110.45 (10)	N11—C51—H51	127.00
O31—C3—C2	109.98 (9)	C41—C51—H51	127.00
C2—C3—C3i	112.11 (10)
C21—N11—C51—C41	−0.42 (16)	C1—C2—C3—C3i	−177.68 (10)
C51—N11—C21—N31	0.31 (16)	C1—C2—C3—O31	62.76 (12)
C21—N31—C41—C51	−0.19 (16)	O21—C2—C3—C3i	59.76 (13)
C41—N31—C21—N11	−0.08 (16)	O31—C3—C3i—O31i	179.98 (12)
O11—C1—C2—O21	5.67 (17)	C2—C3—C3i—O31i	59.01 (12)
O12—C1—C2—O21	−174.06 (11)	C2—C3—C3i—C2i	−179.98 (12)
O12—C1—C2—C3	62.63 (14)	O31—C3—C3i—C2i	−59.01 (12)
O11—C1—C2—C3	−117.63 (13)	N31—C41—C51—N11	0.36 (16)
O21—C2—C3—O31	−59.81 (13)

D—H···A	D—H	H···A	D···A	D—H···A
N11—H11···O21	0.89 (2)	1.84 (2)	2.7311 (15)	175.9 (19)
N31—H31···O12ii	0.890 (18)	1.795 (19)	2.6810 (14)	174 (2)
O21—H22···O1W	0.87 (2)	1.76 (2)	2.6324 (15)	177 (2)
O31—H32···O12iii	0.83 (2)	1.89 (2)	2.7104 (13)	170.9 (16)
O1W—H11W···O11iv	0.87 (3)	1.82 (3)	2.6799 (14)	170.9 (18)
O1W—H12W···O31v	0.86 (3)	1.94 (3)	2.7763 (15)	164.4 (19)
C21—H21···O11vi	0.95	2.32	3.0935 (17)	138
C41—H41···O11vii	0.95	2.42	3.2273 (18)	142
C51—H51···O1Wviii	0.95	2.34	3.2827 (18)	173

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N11—H11⋯O21	0.89 (2)	1.84 (2)	2.7311 (15)	175.9 (19)
N31—H31⋯O12i	0.890 (18)	1.795 (19)	2.6810 (14)	174 (2)
O21—H22⋯O1W	0.87 (2)	1.76 (2)	2.6324 (15)	177 (2)
O31—H32⋯O12ii	0.83 (2)	1.89 (2)	2.7104 (13)	170.9 (16)
O1W—H11W⋯O11iii	0.87 (3)	1.82 (3)	2.6799 (14)	170.9 (18)
O1W—H12W⋯O31iv	0.86 (3)	1.94 (3)	2.7763 (15)	164.4 (19)

Symmetry codes: (i) ; (ii) ; (iii) ; (iv) .