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ISSN: 2056-9890

Tetra­ethyl­ammonium bicarbonate trihydrate

aHenan University of Traditional Chinese Medicine, Zhengzhou 450008, People's Republic of China, and bKey Laboratory of Polymer Materials of Gansu Province, Ministry of Education, College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou 730070, Gansu, People's Republic of China
*Correspondence e-mail: yangyx80@nwnu.edu.cn

(Received 7 June 2011; accepted 1 July 2011; online 9 July 2011)

In the title compound, C8H20N+·CHO3·3H2O, the bicarbon­ate anion, which has a small mean deviation from the plane of 0.0014 Å, fully utilises its three O and one H atom to form various O—H⋯O hydrogen bonds with the three water mol­ecules in the asymmetric unit, generating a hydrogen-bonded layer, which extends along (10[\overline{1}]). The tetra­ethyl­ammonium cations, as the guest species, are accommodated between every two neighboring layers, constructing a sandwich-like structure with an inter­layer distance of 7.28 Å.

Related literature

For the crystal structure of tetra­ethyl­ammonium bicarbonate monohydrate clathrate, see: Li et al. (2003[Li, Q. & Hu, H. Y. (2003). Beijing Shifan Dax. Xue. Zir. Kex. (J. B. Norm. Univ.), 39, 645-649.]). For O—H⋯O hydrogen bonds, see: Steiner (2002[Steiner, T. (2002). Angew. Chem. Int. Ed. 41, 48-76.]). For polymorphism see Kumar et al. (2002[Kumar, V. S. S., Addlagatta, A., Nangia, A., Robinson, W. T., Broder, C. K., Mondal, R., Evans, I. R., Howard, J. A. K. & Allen, F. H. (2002). Angew. Chem. Int. Ed. 41, 3848-3851.]).

[Scheme 1]

Experimental

Crystal data
  • C8H20N+·CHO3·3H2O

  • Mr = 245.32

  • Monoclinic, P 21 /n

  • a = 7.6633 (1) Å

  • b = 12.9627 (3) Å

  • c = 14.2683 (3) Å

  • β = 99.932 (1)°

  • V = 1396.13 (5) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.10 mm−1

  • T = 296 K

  • 0.61 × 0.29 × 0.18 mm

Data collection
  • Bruker SMART APEX diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.854, Tmax = 1.000

  • 8465 measured reflections

  • 3480 independent reflections

  • 2466 reflections with I > 2σ(I)

  • Rint = 0.018

Refinement
  • R[F2 > 2σ(F2)] = 0.045

  • wR(F2) = 0.138

  • S = 1.02

  • 3480 reflections

  • 166 parameters

  • 10 restraints

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

  • Δρmax = 0.16 e Å−3

  • Δρmin = −0.17 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O1W—H1WA⋯O2i 0.83 (1) 2.00 (1) 2.8239 (16) 177 (2)
O1W—H1WB⋯O3Wii 0.82 (1) 2.05 (1) 2.8666 (19) 173 (2)
O2W—H2WA⋯O1 0.83 (1) 1.97 (1) 2.7980 (15) 172 (2)
O2W—H2WB⋯O1Wiii 0.82 (1) 2.01 (1) 2.8229 (16) 171 (2)
O3—H3⋯O1iv 0.83 (1) 1.85 (1) 2.6676 (15) 172 (2)
O3W—H3WA⋯O2 0.83 (1) 2.06 (1) 2.8422 (18) 157 (2)
O3W—H3WB⋯O2W 0.81 (1) 2.07 (2) 2.8099 (19) 152 (3)
Symmetry codes: (i) -x, -y+1, -z+1; (ii) [x+{\script{1\over 2}}, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]; (iii) [-x+{\script{1\over 2}}, y+{\script{1\over 2}}, -z+{\script{3\over 2}}]; (iv) -x, -y+2, -z+2.

Data collection: APEX2 (Bruker, 2009[Bruker (2009). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconson, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconson, 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: SHELXL97 and publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Supporting information


Comment top

Polymorphism is the existence of the same chemical substance in at least two different crystalline arrangements of molecules (Kumar et al. 2002). It is helpful to understand polymorphism to explore different crystal structures which are not qualified polymorphs but are also constructed with the same components. In 2003, the crystal structure of tetraethylammonium bicarbonate monohydrate clathrate (C8H20N+.CHO3-.H2O, 1) has been reported (Li et al. 2003). Here we reported the crystal structure of tetraethylammonium bicarbonate trihydrate clathrate (C8H20N+.CHO3-.3H2O, 2), in which the same components were used to obtain the crystal but the difference of the amount of water molecules in the asymmetric unit results in the final different packing model compared with compound 1. In addition, it should be noted that, in our experiment, 4,4'-oxybis(benzoic acid) was used to be the host molecule to obtain the acid-base inclusion compound, but after the data collection and determination, it was found that bicarbonate anion, which was finally determined according to the corresponding C—O bond lengths and O—C—O angles existed in the similar crystal structure of compound 1, take the place of the acid to interact with the related base to generate compound 2. In compound 1, one bicarbonate anion and one water molecule interacting with each other through O—H···O hydrogen bonds constitute a zigzag ribbon and are arranged in un-closed channels generated from tetraethylammonium cations. Comparatively, one bicarbonate anion and three water molecules in compound 2 form more O—H···O hydrogen bonds to construct the hydrogen-bonded layer and tetraethylammonium cations are contained between the layers to display the typical sandwich-like structure. Obviously, the amount of water molecules has significant effect on constructing different crystal structure between compound 1 and2. Noticeably, in compound 2, the strongest O—H···O hydrogen bond is between the centro-symmetric related bicarbonate anions (the distance of O···O is 2.6654 (16) Å) and other weaker O—H···O contacts involve the participation of water molecules (the corresponding values are from 2.7991 (16) Å to 2.868 (2) Å), which can be compared with the related O···O intervals of compound 1 (O···O distances are 2.619 Å and 2.868 Å) and the corresponding values (2.68 Å ~ 3.11 Å) of the reference (Steiner, 2002).

Related literature top

For the crystal structure of tetraethylammonium bicarbonate monohydrate clathrate, see: Li et al. (2003). For O—H···O hydrogen bonds, see: Steiner (2002). For polymorphism see Kumar et al. (2002).

Experimental top

4,4'-Oxybis(benzoic acid) (0.25 mmol, 0.065 g) was dissolved in a water-ethanol (50 ml/100 ml v/v) mixture. Tetraethylammonium hydroxide (25% aqueous solution) was added to neutralize the acid. The mixture was stirred for about 2 h and set aside to crystallize. Unexpectedly, the crystals involved 4,4'-oxybis(benzoic acid) were not obtained. Instead, colorless block crystals of the title compound were separated after several weeks.

Refinement top

Carbon-bound H-atoms were placed in calculated positions (C—H: 0.96 Å for CH3 group and 0.97 Å for CH2 group) and were included in the refinement in the riding model approximation, with U(H) set to 1.2Ueq(C) for CH2 group and 1.5Ueq(C) for CH3 group. The anion and water H-atoms were located in a difference Fourier map, and were refined with a distance restraint of O—H 0.82±0.01 Å and with U(H) set to 1.5Ueq(O). Meanwhile, for water molecules, H—H distances were also restrained within 1.41±0.02 Å to meet the needs of H—O—H angles.

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); 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: SHELXL97 (Sheldrick, 2008) and publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. Thermal ellipsoid plot of the title compound at the 30% probability level; hydrogen atoms are drawn as spheres of arbitrary radius.
[Figure 2] Fig. 2. Packing diagram of the title compound; all hydrogen atoms bonded to carbon are omitted for clarity and the cations are represented with the open bonds.
[Figure 3] Fig. 3. Hydrogen-bonded linking pattern of the host layer in the crystal structure of the title compound.
Tetraethylammonium bicarbonate trihydrate top
Crystal data top
C8H20N+·CHO3·3H2OF(000) = 544
Mr = 245.32Dx = 1.167 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 2627 reflections
a = 7.6633 (1) Åθ = 3.1–26.7°
b = 12.9627 (3) ŵ = 0.10 mm1
c = 14.2683 (3) ÅT = 296 K
β = 99.932 (1)°Block, colourless
V = 1396.13 (5) Å30.61 × 0.29 × 0.18 mm
Z = 4
Data collection top
Bruker SMART APEX
diffractometer
3480 independent reflections
Radiation source: fine-focus sealed tube2466 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.018
phi and ω scansθmax = 28.5°, θmin = 2.1°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
h = 108
Tmin = 0.854, Tmax = 1.000k = 1715
8465 measured reflectionsl = 1219
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)] = 0.045Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.138H atoms treated by a mixture of independent and constrained refinement
S = 1.02 w = 1/[σ2(Fo2) + (0.0697P)2 + 0.1916P]
where P = (Fo2 + 2Fc2)/3
3480 reflections(Δ/σ)max = 0.001
166 parametersΔρmax = 0.16 e Å3
10 restraintsΔρmin = 0.17 e Å3
Crystal data top
C8H20N+·CHO3·3H2OV = 1396.13 (5) Å3
Mr = 245.32Z = 4
Monoclinic, P21/nMo Kα radiation
a = 7.6633 (1) ŵ = 0.10 mm1
b = 12.9627 (3) ÅT = 296 K
c = 14.2683 (3) Å0.61 × 0.29 × 0.18 mm
β = 99.932 (1)°
Data collection top
Bruker SMART APEX
diffractometer
3480 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
2466 reflections with I > 2σ(I)
Tmin = 0.854, Tmax = 1.000Rint = 0.018
8465 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.04510 restraints
wR(F2) = 0.138H atoms treated by a mixture of independent and constrained refinement
S = 1.02Δρmax = 0.16 e Å3
3480 reflectionsΔρmin = 0.17 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 F^2^ against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F^2^, conventional R-factors R are based on F, with F set to zero for negative F^2^. The threshold expression of F^2^ > σ(F^2^) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F^2^ 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
N10.23247 (12)0.27367 (8)0.83104 (6)0.0337 (2)
O10.02644 (15)0.87654 (8)0.97489 (8)0.0608 (3)
O1W0.24867 (16)0.07251 (10)0.33750 (8)0.0642 (3)
H1WA0.218 (3)0.0994 (16)0.2845 (10)0.096*
H1WB0.308 (3)0.0199 (12)0.3364 (16)0.096*
C10.08821 (18)0.89307 (11)0.90217 (9)0.0453 (3)
O20.14805 (14)0.82902 (9)0.84014 (8)0.0594 (3)
O2W0.21273 (15)0.68993 (10)0.99356 (9)0.0641 (3)
H2WA0.165 (3)0.7475 (10)0.9923 (15)0.096*
H2WB0.212 (3)0.6570 (14)1.0426 (11)0.096*
C20.40040 (16)0.21074 (11)0.86043 (9)0.0443 (3)
H2A0.41580.16630.80770.053*
H2B0.50040.25770.87140.053*
O30.15534 (16)0.98874 (8)0.88939 (8)0.0632 (3)
H30.109 (3)1.0260 (15)0.9338 (12)0.095*
O3W0.05481 (19)0.61659 (11)0.84914 (10)0.0767 (4)
H3WA0.110 (3)0.6718 (13)0.8393 (18)0.115*
H3WB0.017 (3)0.6182 (19)0.8983 (12)0.115*
C30.4058 (3)0.14500 (13)0.94748 (12)0.0654 (4)
H3A0.51640.10860.96020.098*
H3B0.30990.09640.93700.098*
H3C0.39450.18801.00090.098*
C40.26289 (17)0.33841 (11)0.74702 (9)0.0428 (3)
H4A0.36560.38190.76710.051*
H4B0.29070.29260.69790.051*
C50.1098 (2)0.40604 (13)0.70431 (11)0.0599 (4)
H5A0.14070.44390.65170.090*
H5B0.08320.45350.75160.090*
H5C0.00790.36390.68250.090*
C60.19457 (17)0.34029 (10)0.91255 (9)0.0418 (3)
H6A0.08770.37970.89070.050*
H6B0.17100.29540.96330.050*
C70.3400 (2)0.41413 (12)0.95290 (11)0.0542 (4)
H7A0.30470.45261.00400.081*
H7B0.36210.46070.90400.081*
H7C0.44600.37610.97650.081*
C80.07102 (17)0.20495 (11)0.80381 (10)0.0460 (3)
H8A0.05910.16200.85800.055*
H8B0.03340.24840.79050.055*
C90.0748 (2)0.13609 (13)0.71913 (13)0.0655 (4)
H9A0.03190.09580.70700.098*
H9B0.17540.09090.73210.098*
H9C0.08340.17760.66440.098*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0328 (5)0.0355 (5)0.0333 (5)0.0040 (4)0.0068 (4)0.0037 (4)
O10.0708 (7)0.0493 (6)0.0566 (6)0.0134 (5)0.0049 (5)0.0020 (5)
O1W0.0656 (7)0.0716 (8)0.0541 (6)0.0014 (6)0.0067 (5)0.0011 (6)
C10.0479 (7)0.0450 (8)0.0446 (7)0.0014 (6)0.0123 (6)0.0060 (6)
O20.0651 (6)0.0528 (6)0.0577 (6)0.0023 (5)0.0035 (5)0.0053 (5)
O2W0.0592 (6)0.0610 (7)0.0716 (7)0.0131 (5)0.0106 (5)0.0068 (6)
C20.0401 (6)0.0455 (8)0.0464 (7)0.0048 (5)0.0052 (5)0.0046 (6)
O30.0769 (8)0.0459 (6)0.0593 (7)0.0090 (5)0.0094 (5)0.0057 (5)
O3W0.0932 (10)0.0618 (8)0.0705 (8)0.0027 (7)0.0013 (7)0.0066 (6)
C30.0826 (11)0.0567 (10)0.0540 (9)0.0176 (8)0.0034 (8)0.0062 (7)
C40.0467 (7)0.0460 (7)0.0373 (6)0.0067 (6)0.0116 (5)0.0010 (5)
C50.0662 (9)0.0568 (9)0.0532 (8)0.0010 (7)0.0005 (7)0.0136 (7)
C60.0430 (6)0.0458 (7)0.0383 (6)0.0007 (5)0.0117 (5)0.0073 (5)
C70.0627 (8)0.0503 (8)0.0483 (8)0.0063 (7)0.0054 (6)0.0153 (6)
C80.0411 (6)0.0475 (8)0.0488 (7)0.0141 (6)0.0060 (5)0.0028 (6)
C90.0682 (10)0.0556 (10)0.0685 (10)0.0155 (8)0.0001 (8)0.0204 (8)
Geometric parameters (Å, º) top
N1—C41.5141 (15)C3—H3C0.9600
N1—C61.5162 (15)C4—C51.507 (2)
N1—C81.5197 (15)C4—H4A0.9700
N1—C21.5203 (16)C4—H4B0.9700
O1—C11.2569 (17)C5—H5A0.9600
O1W—H1WA0.829 (9)C5—H5B0.9600
O1W—H1WB0.823 (9)C5—H5C0.9600
C1—O21.2422 (17)C6—C71.5064 (19)
C1—O31.3429 (18)C6—H6A0.9700
O2W—H2WA0.830 (9)C6—H6B0.9700
O2W—H2WB0.820 (9)C7—H7A0.9600
C2—C31.501 (2)C7—H7B0.9600
C2—H2A0.9700C7—H7C0.9600
C2—H2B0.9700C8—C91.506 (2)
O3—H30.827 (10)C8—H8A0.9700
O3W—H3WA0.831 (9)C8—H8B0.9700
O3W—H3WB0.812 (9)C9—H9A0.9600
C3—H3A0.9600C9—H9B0.9600
C3—H3B0.9600C9—H9C0.9600
C4—N1—C6111.57 (10)C4—C5—H5A109.5
C4—N1—C8110.62 (9)C4—C5—H5B109.5
C6—N1—C8105.95 (9)H5A—C5—H5B109.5
C4—N1—C2106.09 (9)C4—C5—H5C109.5
C6—N1—C2111.05 (9)H5A—C5—H5C109.5
C8—N1—C2111.66 (10)H5B—C5—H5C109.5
H1WA—O1W—H1WB113.7 (19)C7—C6—N1115.34 (10)
O2—C1—O1126.42 (14)C7—C6—H6A108.4
O2—C1—O3115.77 (12)N1—C6—H6A108.4
O1—C1—O3117.81 (13)C7—C6—H6B108.4
H2WA—O2W—H2WB114.8 (19)N1—C6—H6B108.4
C3—C2—N1115.72 (12)H6A—C6—H6B107.5
C3—C2—H2A108.4C6—C7—H7A109.5
N1—C2—H2A108.4C6—C7—H7B109.5
C3—C2—H2B108.4H7A—C7—H7B109.5
N1—C2—H2B108.4C6—C7—H7C109.5
H2A—C2—H2B107.4H7A—C7—H7C109.5
C1—O3—H3109.4 (16)H7B—C7—H7C109.5
H3WA—O3W—H3WB112 (2)C9—C8—N1115.14 (11)
C2—C3—H3A109.5C9—C8—H8A108.5
C2—C3—H3B109.5N1—C8—H8A108.5
H3A—C3—H3B109.5C9—C8—H8B108.5
C2—C3—H3C109.5N1—C8—H8B108.5
H3A—C3—H3C109.5H8A—C8—H8B107.5
H3B—C3—H3C109.5C8—C9—H9A109.5
C5—C4—N1115.30 (11)C8—C9—H9B109.5
C5—C4—H4A108.4H9A—C9—H9B109.5
N1—C4—H4A108.4C8—C9—H9C109.5
C5—C4—H4B108.4H9A—C9—H9C109.5
N1—C4—H4B108.4H9B—C9—H9C109.5
H4A—C4—H4B107.5
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1W—H1WA···O2i0.83 (1)2.00 (1)2.8239 (16)177 (2)
O1W—H1WB···O3Wii0.82 (1)2.05 (1)2.8666 (19)173 (2)
O2W—H2WA···O10.83 (1)1.97 (1)2.7980 (15)172 (2)
O2W—H2WB···O1Wiii0.82 (1)2.01 (1)2.8229 (16)171 (2)
O3—H3···O1iv0.83 (1)1.85 (1)2.6676 (15)172 (2)
O3W—H3WA···O20.83 (1)2.06 (1)2.8422 (18)157 (2)
O3W—H3WB···O2W0.81 (1)2.07 (2)2.8099 (19)152 (3)
Symmetry codes: (i) x, y+1, z+1; (ii) x+1/2, y+1/2, z1/2; (iii) x+1/2, y+1/2, z+3/2; (iv) x, y+2, z+2.

Experimental details

Crystal data
Chemical formulaC8H20N+·CHO3·3H2O
Mr245.32
Crystal system, space groupMonoclinic, P21/n
Temperature (K)296
a, b, c (Å)7.6633 (1), 12.9627 (3), 14.2683 (3)
β (°) 99.932 (1)
V3)1396.13 (5)
Z4
Radiation typeMo Kα
µ (mm1)0.10
Crystal size (mm)0.61 × 0.29 × 0.18
Data collection
DiffractometerBruker SMART APEX
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.854, 1.000
No. of measured, independent and
observed [I > 2σ(I)] reflections
8465, 3480, 2466
Rint0.018
(sin θ/λ)max1)0.670
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.045, 0.138, 1.02
No. of reflections3480
No. of parameters166
No. of restraints10
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.16, 0.17

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008) and publCIF (Westrip, 2010).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1W—H1WA···O2i0.829 (9)1.996 (9)2.8239 (16)177 (2)
O1W—H1WB···O3Wii0.823 (9)2.048 (10)2.8666 (19)173 (2)
O2W—H2WA···O10.830 (9)1.974 (10)2.7980 (15)172 (2)
O2W—H2WB···O1Wiii0.820 (9)2.010 (10)2.8229 (16)171 (2)
O3—H3···O1iv0.827 (10)1.846 (10)2.6676 (15)172 (2)
O3W—H3WA···O20.831 (9)2.059 (14)2.8422 (18)157 (2)
O3W—H3WB···O2W0.812 (9)2.065 (16)2.8099 (19)152 (3)
Symmetry codes: (i) x, y+1, z+1; (ii) x+1/2, y+1/2, z1/2; (iii) x+1/2, y+1/2, z+3/2; (iv) x, y+2, z+2.
 

Acknowledgements

We thank Northwest Normal University for supporting this study.

References

First citationBruker (2009). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconson, USA.  Google Scholar
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