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ISSN: 2056-9890

Bis(melaminium) tartrate dihydrate

aZhejiang Key Laboratory for Reactive Chemistry on Solid Surfaces, Institute of Physical Chemistry, Zhejiang Normal University, Jinhua, Zhejiang 321004, People's Republic of China
*Correspondence e-mail: sky37@zjnu.cn

(Received 8 March 2009; accepted 26 March 2009; online 31 March 2009)

In the title compound, 2C3H7N6+·C4H4O62−·2H2O, in which the complete anion is generated by crystallographic twofold symmetry, there are O—H⋯O, N—H⋯O and N—H⋯N hydrogen-bonding inter­actions between neighbouring moieties, forming layers parallel to the bc plane. In addition, ππ contacts [centroid–centroid distance = 3.6541 (9) Å] between the six-membered rings of the melamine cations are observed.

Related literature

For general background, see: Row (1999[Row, T. N. G. (1999). Coord. Chem. Rev. 183, 81-100.]); Krische & Lehn (2000[Krische, M. J. & Lehn, J. M. (2000). Struct. Bond. 96, 3-29.]); Sherrington & Taskinen (2001[Sherrington, D. C. & Taskinen, K. A. (2001). Chem. Soc. Rev. 30, 83-91.]); Marchewka et al. (2003[Marchewka, M. K., Janczak, J., Debrus, S., Baran, J. & Ratajczak, H. (2003). Solid State Sci. 5, 643-652.]); Thushari et al. (2005[Thushari, S., Cha, J. A. K., Sung, H. H.-Y., Chui, S. S.-Y., Leung, A. L.-F., Yen, Y. F. & Williams, I. D. (2005). Chem. Commun. pp. 5515-5517.]). For related structures, see: Udaya Lakshmi et al. (2006[Udaya Lakshmi, K., Thamotharan, S., Ramamurthi, K. & Varghese, B. (2006). Acta Cryst. E62, o455-o457.]).

[Scheme 1]

Experimental

Crystal data
  • 2C3H7N6+·C4H4O62−·2H2O

  • Mr = 436.38

  • Monoclinic, C 2/c

  • a = 7.6963 (9) Å

  • b = 21.955 (3) Å

  • c = 10.7405 (12) Å

  • β = 98.179 (6)°

  • V = 1796.4 (4) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.14 mm−1

  • T = 296 K

  • 0.26 × 0.22 × 0.12 mm

Data collection
  • Bruker APEXII area-detector diffractometer

  • Absorption correction: multiscan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.963, Tmax = 0.980

  • 13436 measured reflections

  • 2047 independent reflections

  • 1712 reflections with I > 2σ(I)

  • Rint = 0.027

Refinement
  • R[F2 > 2σ(F2)] = 0.037

  • wR(F2) = 0.108

  • S = 1.00

  • 2047 reflections

  • 166 parameters

  • 15 restraints

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

  • Δρmax = 0.25 e Å−3

  • Δρmin = −0.24 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O3—H3⋯O2i 0.870 (11) 1.802 (12) 2.6680 (14) 173.2 (16)
N1—H1NA⋯O1 0.884 (13) 2.271 (14) 3.0466 (19) 146.3 (16)
N1—H1NB⋯N4ii 0.879 (13) 2.151 (13) 3.0287 (19) 177.3 (17)
N2—H2NA⋯O3 0.889 (15) 2.093 (15) 2.8333 (16) 140.2 (14)
N2—H2NA⋯O1 0.889 (15) 2.190 (15) 2.9497 (18) 143.2 (14)
N3—H3NA⋯O1Wiii 0.872 (14) 2.261 (19) 2.8609 (18) 125.9 (15)
N3—H3NA⋯O3 0.872 (14) 2.573 (16) 3.2241 (18) 132.2 (16)
N3—H3NB⋯N6iv 0.900 (14) 2.133 (14) 3.0313 (19) 176.2 (18)
N5—H5NA⋯O1Wv 0.901 (13) 1.940 (14) 2.8148 (16) 163.2 (15)
N5—H5NB⋯O2vi 0.895 (13) 2.153 (15) 2.9581 (16) 149.4 (15)
O1W—H1WA⋯O1 0.858 (14) 1.852 (14) 2.6861 (16) 163.8 (17)
O1W—H1WB⋯O2vii 0.804 (13) 2.297 (15) 2.9738 (17) 142.3 (17)
Symmetry codes: (i) [x, -y, z+{\script{1\over 2}}]; (ii) [x-{\script{1\over 2}}, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]; (iii) [-x+1, y, -z+{\script{1\over 2}}]; (iv) [x+{\script{1\over 2}}, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]; (v) [-x+{\script{1\over 2}}, -y+{\script{1\over 2}}, -z]; (vi) [-x+{\script{1\over 2}}, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]; (vii) -x+1, -y, -z.

Data collection: APEX2 (Bruker, 2006[Bruker (2006). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2006[Bruker (2006). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; 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: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

Melamine and its organic and inorganic counterparts can develop supramolecular assemblies via multiple hydrogen bonds (Row, 1999; Krische & Lehn, 2000; Sherrington & Taskinen, 2001; Marchewka et al., 2003), while tartaric acid is a small organic molecule [C4H4O6] with a bewildering array of ligation possibilities (Thushari et al., 2005). Herein we report the synthesis and crystal structure of the title compound (I).

In (I) (Fig. 1), the melaminium cations form infinite floors via N—H···N hydrogen bonds and the D-tartrate anions link pair with waters via O—H···O form floors lying between two floors of melaminium. Furthermore, the N—H···O hydrogen bonds connected the neighboring cations floors and anions floors is together into a three-dimensional network. We found that the architecture of compound (I) is similar to bis (melaminium) L– tartrate 2.5-hydrate (Udaya Lakshmi et al., 2006) but not the same, which indicate that using different stereo-chemical configurations can give different three-dimensional arrangements. In addition, ππ contacts [centroid-centroid distance 3.6541 (9) Å] between the six-membered rings of the melamine moieties are observed.

Related literature top

For related literature, see: Krische & Lehn (2000); Udaya Lakshmi et al. (2006); Marchewka et al. (2003); Row (1999); Sherrington & Taskinen (2001); Thushari et al. (2005).

Experimental top

Compound (I) is formed by hydrothermal reaction of D-tartaric acid (1.5 mmol) and Melamine (1 mmol) in 15 ml water for 2 days at 533 K.

Refinement top

The H atoms bonded to C atoms were positioned geometrically [C—H 0.96 Å Uiso(H) = 1.2Ueq(C)]. The H atoms bonded to O atoms were located in a difference Fourier maps and their positions were refined isotropically, with O—H distances fixed by O—H = 0.85 (2) Å and H ··· H = 1.30 (2) Å, their displacement parameters were set to 1.5Ueq(O). The H atoms bonded to N atoms were located in a difference Fourier maps and their positions were refined isotropically, with N—H distances fixed by N—H = 0.90 (2) Å and H ··· H = 1.56 (2) Å, their displacement parameters were set to 1.2Ueq(N).

Computing details top

Data collection: APEX2 (Bruker, 2006); cell refinement: SAINT (Bruker, 2006); data reduction: SAINT (Bruker, 2006); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. View of the molecule of (I), showing the atom-numbering scheme. Displacement ellipsoids plotted at 30% probability level. [The atoms labelled with 'A' are related to the center of inversion].
[Figure 2] Fig. 2. Packing diagram for compound (I). The O—H···O and O—H···N interactions are depicted by dashed lines.
Bis(melaminium) tartrate dihydrate top
Crystal data top
2C3H7N6+·C4H4O62·2H2OF(000) = 920
Mr = 436.38Dx = 1.621 Mg m3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 4811 reflections
a = 7.6963 (9) Åθ = 1.9–27.5°
b = 21.955 (3) ŵ = 0.14 mm1
c = 10.7405 (12) ÅT = 296 K
β = 98.179 (6)°Block, colourless
V = 1796.4 (4) Å30.26 × 0.22 × 0.12 mm
Z = 4
Data collection top
Bruker APEXII area-detector
diffractometer
2047 independent reflections
Radiation source: fine-focus sealed tube1712 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.027
ω scansθmax = 27.5°, θmin = 1.9°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
h = 910
Tmin = 0.963, Tmax = 0.980k = 2728
13436 measured reflectionsl = 1313
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)] = 0.037Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.108H atoms treated by a mixture of independent and constrained refinement
S = 1.00 w = 1/[σ2(Fo2) + (0.059P)2 + 0.9299P]
where P = (Fo2 + 2Fc2)/3
2047 reflections(Δ/σ)max < 0.001
166 parametersΔρmax = 0.25 e Å3
15 restraintsΔρmin = 0.24 e Å3
Crystal data top
2C3H7N6+·C4H4O62·2H2OV = 1796.4 (4) Å3
Mr = 436.38Z = 4
Monoclinic, C2/cMo Kα radiation
a = 7.6963 (9) ŵ = 0.14 mm1
b = 21.955 (3) ÅT = 296 K
c = 10.7405 (12) Å0.26 × 0.22 × 0.12 mm
β = 98.179 (6)°
Data collection top
Bruker APEXII area-detector
diffractometer
2047 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
1712 reflections with I > 2σ(I)
Tmin = 0.963, Tmax = 0.980Rint = 0.027
13436 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.03715 restraints
wR(F2) = 0.108H atoms treated by a mixture of independent and constrained refinement
S = 1.00Δρmax = 0.25 e Å3
2047 reflectionsΔρmin = 0.24 e Å3
166 parameters
Special details top

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
xyzUiso*/Ueq
O10.25143 (17)0.05132 (5)0.11300 (12)0.0603 (3)
O20.17077 (17)0.04576 (5)0.08785 (10)0.0535 (3)
O30.15841 (13)0.05730 (4)0.33946 (9)0.0394 (3)
H30.158 (2)0.0508 (7)0.4193 (11)0.047*
N10.06055 (18)0.17081 (6)0.04393 (13)0.0470 (3)
H1NA0.074 (2)0.1308 (6)0.0459 (17)0.056*
H1NB0.004 (2)0.1902 (7)0.0177 (15)0.056*
N20.23582 (16)0.17105 (6)0.23551 (12)0.0428 (3)
H2NA0.233 (2)0.1306 (7)0.2342 (16)0.051*
N30.4140 (2)0.17049 (7)0.42646 (15)0.0558 (4)
H3NA0.407 (2)0.1308 (7)0.4247 (18)0.067*
H3NB0.477 (2)0.1917 (8)0.4890 (16)0.067*
N40.32789 (15)0.26210 (5)0.33724 (11)0.0373 (3)
N50.22621 (18)0.35022 (5)0.24256 (11)0.0451 (3)
H5NA0.157 (2)0.3702 (8)0.1812 (13)0.054*
H5NB0.282 (2)0.3704 (8)0.3088 (13)0.054*
N60.13898 (15)0.26268 (5)0.13787 (10)0.0353 (3)
C10.18246 (18)0.00368 (6)0.14673 (13)0.0392 (3)
C20.09995 (16)0.00520 (5)0.26757 (11)0.0308 (3)
H2A0.13290.03090.31570.037*
C30.23110 (16)0.29059 (6)0.23929 (11)0.0338 (3)
C40.14503 (16)0.20248 (6)0.13831 (13)0.0352 (3)
C50.32593 (17)0.20212 (6)0.33379 (13)0.0386 (3)
O1W0.45183 (14)0.06665 (5)0.06993 (11)0.0465 (3)
H1WA0.391 (2)0.0544 (8)0.0137 (16)0.056*
H1WB0.535 (2)0.0446 (8)0.0730 (17)0.056*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0750 (8)0.0567 (7)0.0575 (7)0.0020 (6)0.0378 (6)0.0128 (6)
O20.0879 (8)0.0446 (6)0.0312 (5)0.0254 (5)0.0197 (5)0.0046 (4)
O30.0533 (6)0.0362 (5)0.0272 (5)0.0122 (4)0.0010 (4)0.0008 (4)
N10.0582 (8)0.0324 (6)0.0480 (8)0.0069 (5)0.0006 (6)0.0048 (5)
N20.0496 (7)0.0278 (6)0.0494 (7)0.0002 (5)0.0013 (5)0.0020 (5)
N30.0641 (8)0.0382 (7)0.0591 (9)0.0069 (6)0.0120 (7)0.0110 (6)
N40.0433 (6)0.0337 (6)0.0333 (6)0.0020 (4)0.0003 (5)0.0027 (4)
N50.0658 (8)0.0288 (6)0.0358 (7)0.0001 (5)0.0097 (6)0.0001 (5)
N60.0434 (6)0.0308 (6)0.0310 (6)0.0022 (4)0.0033 (5)0.0001 (4)
C10.0454 (7)0.0420 (8)0.0320 (7)0.0151 (6)0.0118 (5)0.0100 (5)
C20.0422 (7)0.0264 (6)0.0236 (6)0.0017 (5)0.0046 (5)0.0031 (4)
C30.0395 (6)0.0329 (7)0.0291 (6)0.0004 (5)0.0048 (5)0.0012 (5)
C40.0366 (6)0.0328 (7)0.0372 (7)0.0028 (5)0.0086 (5)0.0003 (5)
C50.0383 (6)0.0359 (7)0.0412 (7)0.0022 (5)0.0044 (5)0.0051 (6)
O1W0.0443 (6)0.0467 (6)0.0496 (6)0.0051 (4)0.0102 (5)0.0143 (5)
Geometric parameters (Å, º) top
O1—C11.2497 (18)N4—C51.3174 (18)
O2—C11.2530 (18)N4—C31.3527 (16)
O3—C21.4170 (15)N5—C31.3104 (18)
O3—H30.870 (11)N5—H5NA0.901 (13)
N1—C41.3215 (18)N5—H5NB0.895 (13)
N1—H1NA0.884 (13)N6—C41.3224 (18)
N1—H1NB0.879 (13)N6—C31.3583 (16)
N2—C41.3590 (18)C1—C21.5242 (18)
N2—C51.3610 (18)C2—C2i1.531 (2)
N2—H2NA0.889 (15)C2—H2A0.9600
N3—C51.3193 (18)O1W—H1WA0.858 (14)
N3—H3NA0.872 (14)O1W—H1WB0.804 (13)
N3—H3NB0.900 (14)
C2—O3—H3111.1 (11)O2—C1—C2116.11 (12)
C4—N1—H1NA117.6 (12)O3—C2—C1110.08 (10)
C4—N1—H1NB119.1 (12)O3—C2—C2i111.37 (8)
H1NA—N1—H1NB123.3 (16)C1—C2—C2i108.42 (12)
C4—N2—C5119.39 (13)O3—C2—H2A109.5
C4—N2—H2NA119.1 (11)C1—C2—H2A109.3
C5—N2—H2NA121.5 (11)C2i—C2—H2A108.2
C5—N3—H3NA119.1 (13)N5—C3—N4117.12 (12)
C5—N3—H3NB117.1 (12)N5—C3—N6117.29 (12)
H3NA—N3—H3NB123.8 (17)N4—C3—N6125.59 (13)
C5—N4—C3115.95 (12)N1—C4—N6120.66 (13)
C3—N5—H5NA118.9 (11)N1—C4—N2117.72 (13)
C3—N5—H5NB120.3 (11)N6—C4—N2121.62 (12)
H5NA—N5—H5NB120.5 (15)N4—C5—N3120.17 (13)
C4—N6—C3115.71 (11)N4—C5—N2121.69 (12)
O1—C1—O2125.57 (13)N3—C5—N2118.14 (14)
O1—C1—C2118.30 (13)H1WA—O1W—H1WB110.6 (16)
O1—C1—C2—O315.91 (17)C3—N6—C4—N1179.76 (12)
O2—C1—C2—O3165.79 (11)C3—N6—C4—N20.99 (18)
O1—C1—C2—C2i106.14 (12)C5—N2—C4—N1179.33 (13)
O2—C1—C2—C2i72.17 (12)C5—N2—C4—N61.4 (2)
C5—N4—C3—N5177.80 (13)C3—N4—C5—N3178.79 (13)
C5—N4—C3—N62.34 (19)C3—N4—C5—N21.85 (19)
C4—N6—C3—N5179.21 (12)C4—N2—C5—N40.1 (2)
C4—N6—C3—N40.93 (18)C4—N2—C5—N3179.50 (13)
Symmetry code: (i) x, y, z+1/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O3—H3···O2ii0.87 (1)1.80 (1)2.6680 (14)173 (2)
N1—H1NA···O10.88 (1)2.27 (1)3.0466 (19)146 (2)
N1—H1NB···N4iii0.88 (1)2.15 (1)3.0287 (19)177 (2)
N2—H2NA···O30.89 (2)2.09 (2)2.8333 (16)140 (1)
N2—H2NA···O10.89 (2)2.19 (2)2.9497 (18)143 (1)
N3—H3NA···O1Wiv0.87 (1)2.26 (2)2.8609 (18)126 (2)
N3—H3NA···O30.87 (1)2.57 (2)3.2241 (18)132 (2)
N3—H3NB···N6v0.90 (1)2.13 (1)3.0313 (19)176 (2)
N5—H5NA···O1Wvi0.90 (1)1.94 (1)2.8148 (16)163 (2)
N5—H5NB···O2vii0.90 (1)2.15 (2)2.9581 (16)149 (2)
O1W—H1WA···O10.86 (1)1.85 (1)2.6861 (16)164 (2)
O1W—H1WB···O2viii0.80 (1)2.30 (2)2.9738 (17)142 (2)
Symmetry codes: (ii) x, y, z+1/2; (iii) x1/2, y+1/2, z1/2; (iv) x+1, y, z+1/2; (v) x+1/2, y+1/2, z+1/2; (vi) x+1/2, y+1/2, z; (vii) x+1/2, y+1/2, z+1/2; (viii) x+1, y, z.

Experimental details

Crystal data
Chemical formula2C3H7N6+·C4H4O62·2H2O
Mr436.38
Crystal system, space groupMonoclinic, C2/c
Temperature (K)296
a, b, c (Å)7.6963 (9), 21.955 (3), 10.7405 (12)
β (°) 98.179 (6)
V3)1796.4 (4)
Z4
Radiation typeMo Kα
µ (mm1)0.14
Crystal size (mm)0.26 × 0.22 × 0.12
Data collection
DiffractometerBruker APEXII area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.963, 0.980
No. of measured, independent and
observed [I > 2σ(I)] reflections
13436, 2047, 1712
Rint0.027
(sin θ/λ)max1)0.650
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.037, 0.108, 1.00
No. of reflections2047
No. of parameters166
No. of restraints15
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.25, 0.24

Computer programs: APEX2 (Bruker, 2006), SAINT (Bruker, 2006), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O3—H3···O2i0.870 (11)1.802 (12)2.6680 (14)173.2 (16)
N1—H1NA···O10.884 (13)2.271 (14)3.0466 (19)146.3 (16)
N1—H1NB···N4ii0.879 (13)2.151 (13)3.0287 (19)177.3 (17)
N2—H2NA···O30.889 (15)2.093 (15)2.8333 (16)140.2 (14)
N2—H2NA···O10.889 (15)2.190 (15)2.9497 (18)143.2 (14)
N3—H3NA···O1Wiii0.872 (14)2.261 (19)2.8609 (18)125.9 (15)
N3—H3NA···O30.872 (14)2.573 (16)3.2241 (18)132.2 (16)
N3—H3NB···N6iv0.900 (14)2.133 (14)3.0313 (19)176.2 (18)
N5—H5NA···O1Wv0.901 (13)1.940 (14)2.8148 (16)163.2 (15)
N5—H5NB···O2vi0.895 (13)2.153 (15)2.9581 (16)149.4 (15)
O1W—H1WA···O10.858 (14)1.852 (14)2.6861 (16)163.8 (17)
O1W—H1WB···O2vii0.804 (13)2.297 (15)2.9738 (17)142.3 (17)
Symmetry codes: (i) x, y, z+1/2; (ii) x1/2, y+1/2, z1/2; (iii) x+1, y, z+1/2; (iv) x+1/2, y+1/2, z+1/2; (v) x+1/2, y+1/2, z; (vi) x+1/2, y+1/2, z+1/2; (vii) x+1, y, z.
 

References

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