supplementary materials


pk2077 scheme

Acta Cryst. (2008). E64, o400    [ doi:10.1107/S1600536807068122 ]

Ethane-1,2-diylbis(methylphosphinic acid)

G. J. Reiss and J. S. Engel

Abstract top

In the title compound, C4H12O4P2, there are two crystallographically independent half-molecules in the asymmetric unit, both molecules lying on centres of symmetry. Each molecule is connected on both sides to neighbouring molecules via strong O-H...O hydrogen bonds. The -POOH groups accept and donate one hydrogen bond in interactions with the neighbouring -POOH group of the adjacent molecule, to give one-dimensional chains along [10\overline{1}]. As each phosphinic acid group donates and accepts one hydrogen bond, the connection between the molecules is best described by a ring motif which can be classified by the Etter symbol R22(8).

Comment top

The title compound, [HOO(CH3)P-(CH2)2-P(CH3)OOH, crystallizes in the monoclinic centrosymmetric space group P21/c with two crystallographically independent molecules in the asymmetric unit both of them lying on a centre of symmetry. The molecules are connected on both sides to the next molecules via strong O—H···H hydrogen bonds. The bond lengths and angles in the two crystallographic independent molecules are identical within the ranges of their standard uncertainties. As each posphinic acid group donates and accepts one hydrogen bond the motif of this connection between the molecules is best described by an eight-membered ring (Fig.1) which can be classified by the Etter symbol R22(8) (Etter et al., 1990). A motif which is well known for acetic acid and its derivatives. Each –POOH group accepts and donates one hydrogen bond to the neighbouring –POOH groups of the next molecules to give a one-dimensional chains along [10–1]. This was surprising to us, as the very similar ethane-1,2-diylbis(phosphinic acid) forms a two-dimensional hydrogen bonded network (Bruckmann et al., 1999).

Related literature top

For related literature, see: Bruckmann et al. (1999); Etter et al. (1990); Sicken et al. (2000).

Experimental top

The title compound is generally available by methods described in the literature (Sicken et al., 2000). Recrystallization of the raw material from ethanolic solution at room temperature gave block shaped, colourless crystals.

Refinement top

After refinement of all non-hydrogen atoms using anisotropic displacement parameters, all H atom positions were obtained from successive difference Fourier synthesis. Atom coordinates as well as individual Uiso values are refined freely for each hydrogen atom.

Computing details top

Data collection: R3m/V Software (Siemens, 1989); cell refinement: R3m/V Software (Siemens, 1989); data reduction: R3m/V Software (Siemens, 1989); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: DIAMOND (Brandenburg, 2001); software used to prepare material for publication: SHELXL97 (Sheldrick, 1997).

Figures top
[Figure 1] Fig. 1. : Part of the hydrogen bonded chain of the title structure. (displacement ellipsoids at the 50% probability level, H-atoms drawn with arbitrary radius, ' = -x, 1 - y, 2 - z; '' = 1 - x, 1 - y, 1 - z)
Ethane-1,2-diylbis(methylphosphinic acid) top
Crystal data top
C4H12O4P2F000 = 392
Mr = 186.08Dx = 1.458 Mg m3
Monoclinic, P21/cMo Kα radiation
λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 37 reflections
a = 6.7761 (18) Åθ = 5.1–14.3º
b = 18.703 (8) ŵ = 0.47 mm1
c = 6.8401 (15) ÅT = 290 (2) K
β = 102.09 (3)ºBlock, colourless
V = 847.7 (5) Å30.40 × 0.35 × 0.30 mm
Z = 4
Data collection top
Nicolet/Siemens P21/P3-four-circle
diffractometer
Rint = 0.023
Radiation source: fine-focus sealed tubeθmax = 30.0º
Monochromator: graphiteθmin = 2.2º
T = 290(2) Kh = 0→9
ω scansk = 26→26
Absorption correction: nonel = 9→9
4847 measured reflections3 standard reflections
2466 independent reflections every 100 reflections
1879 reflections with I > 2σ(I) intensity decay: none
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.035All H-atom parameters refined
wR(F2) = 0.079  w = 1/[σ2(Fo2) + (0.025P)2 + 0.41P]
where P = (Fo2 + 2Fc2)/3
S = 1.01(Δ/σ)max = 0.003
2466 reflectionsΔρmax = 0.35 e Å3
139 parametersΔρmin = 0.34 e Å3
Primary atom site location: structure-invariant direct methodsExtinction correction: none
Crystal data top
C4H12O4P2V = 847.7 (5) Å3
Mr = 186.08Z = 4
Monoclinic, P21/cMo Kα
a = 6.7761 (18) ŵ = 0.47 mm1
b = 18.703 (8) ÅT = 290 (2) K
c = 6.8401 (15) Å0.40 × 0.35 × 0.30 mm
β = 102.09 (3)º
Data collection top
Nicolet/Siemens P21/P3-four-circle
diffractometer
Rint = 0.023
Absorption correction: none3 standard reflections
4847 measured reflections every 100 reflections
2466 independent reflections intensity decay: none
1879 reflections with I > 2σ(I)
Refinement top
R[F2 > 2σ(F2)] = 0.035139 parameters
wR(F2) = 0.079All H-atom parameters refined
S = 1.01Δρmax = 0.35 e Å3
2466 reflectionsΔρmin = 0.34 e Å3
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 > 2σ(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
P10.10537 (7)0.60187 (2)0.89929 (7)0.03542 (12)
O10.0298 (2)0.59213 (9)0.6716 (2)0.0477 (3)
H10.114 (6)0.606 (2)0.586 (6)0.145 (15)*
O20.32968 (19)0.59006 (8)0.96702 (19)0.0455 (3)
C10.0385 (5)0.68801 (12)0.9733 (4)0.0563 (6)
H110.067 (4)0.6933 (14)1.116 (4)0.070 (8)*
H120.106 (5)0.7222 (17)0.917 (5)0.094 (10)*
H130.088 (4)0.6940 (15)0.925 (4)0.075 (9)*
C20.0220 (3)0.53869 (9)1.0246 (3)0.0371 (4)
H210.017 (3)0.5445 (12)1.163 (3)0.047 (6)*
H220.157 (3)0.5475 (12)0.984 (3)0.051 (6)*
P20.48253 (7)0.61724 (2)0.51341 (7)0.03302 (11)
O30.25753 (19)0.62778 (7)0.44442 (18)0.0412 (3)
O40.5560 (2)0.62903 (7)0.7409 (2)0.0421 (3)
H40.470 (5)0.6132 (18)0.826 (5)0.117 (12)*
C30.6086 (4)0.67852 (12)0.3826 (4)0.0501 (5)
H310.575 (4)0.7228 (16)0.410 (4)0.078 (8)*
H320.565 (4)0.6729 (14)0.247 (4)0.065 (8)*
H330.738 (4)0.6751 (15)0.426 (4)0.079 (9)*
C40.5508 (3)0.52908 (9)0.4481 (3)0.0343 (3)
H410.693 (3)0.5257 (11)0.494 (3)0.042 (5)*
H420.513 (3)0.5270 (11)0.311 (3)0.044 (6)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
P10.0352 (2)0.0375 (2)0.0329 (2)0.00097 (17)0.00569 (17)0.00385 (18)
O10.0359 (7)0.0712 (10)0.0338 (7)0.0062 (6)0.0024 (5)0.0038 (6)
O20.0350 (7)0.0632 (9)0.0364 (7)0.0004 (6)0.0030 (5)0.0047 (6)
C10.0677 (16)0.0365 (10)0.0624 (16)0.0033 (10)0.0087 (12)0.0018 (10)
C20.0403 (9)0.0362 (9)0.0361 (9)0.0017 (7)0.0108 (7)0.0015 (7)
P20.0359 (2)0.02862 (19)0.0346 (2)0.00337 (16)0.00759 (17)0.00217 (17)
O30.0379 (7)0.0472 (7)0.0371 (7)0.0038 (5)0.0047 (5)0.0049 (5)
O40.0374 (7)0.0493 (8)0.0378 (7)0.0064 (6)0.0037 (5)0.0068 (6)
C30.0576 (14)0.0369 (10)0.0563 (13)0.0105 (9)0.0133 (11)0.0095 (9)
C40.0380 (9)0.0299 (8)0.0357 (9)0.0019 (7)0.0095 (7)0.0018 (7)
Geometric parameters (Å, °) top
P1—O21.5096 (14)P2—O31.5115 (14)
P1—O11.5452 (15)P2—O41.5468 (14)
P1—C11.776 (2)P2—C31.779 (2)
P1—C21.7850 (19)P2—C41.7942 (19)
O1—H10.94 (4)O4—H40.95 (4)
C1—H110.96 (3)C3—H310.89 (3)
C1—H120.92 (3)C3—H320.92 (3)
C1—H130.86 (3)C3—H330.87 (3)
C2—C2i1.529 (3)C4—C4ii1.539 (3)
C2—H210.93 (2)C4—H410.95 (2)
C2—H220.91 (2)C4—H420.92 (2)
O2—P1—O1113.08 (8)O3—P2—O4112.74 (8)
O2—P1—C1110.24 (12)O3—P2—C3108.55 (11)
O1—P1—C1110.11 (12)O4—P2—C3109.08 (11)
O2—P1—C2108.23 (9)O3—P2—C4109.76 (8)
O1—P1—C2108.33 (9)O4—P2—C4109.63 (8)
C1—P1—C2106.60 (11)C3—P2—C4106.90 (11)
P1—O1—H1119 (2)P2—O4—H4118 (2)
P1—C1—H11112.0 (16)P2—C3—H31108.9 (18)
P1—C1—H12109.5 (19)P2—C3—H32110.5 (16)
H11—C1—H12110 (2)H31—C3—H32106 (2)
P1—C1—H13107.7 (19)P2—C3—H33109.7 (19)
H11—C1—H13110 (2)H31—C3—H33106 (3)
H12—C1—H13107 (3)H32—C3—H33115 (2)
C2i—C2—P1112.62 (17)C4ii—C4—P2111.78 (16)
C2i—C2—H21107.8 (14)C4ii—C4—H41108.8 (12)
P1—C2—H21110.3 (13)P2—C4—H41106.0 (12)
C2i—C2—H22109.4 (15)C4ii—C4—H42112.7 (13)
P1—C2—H22106.6 (14)P2—C4—H42105.1 (13)
H21—C2—H22110.1 (18)H41—C4—H42112.3 (17)
O2—P1—C2—C2i61.3 (2)O3—P2—C4—C4ii62.1 (2)
O1—P1—C2—C2i61.7 (2)O4—P2—C4—C4ii62.3 (2)
C1—P1—C2—C2i179.8 (2)C3—P2—C4—C4ii179.64 (19)
Symmetry codes: (i) −x, −y+1, −z+2; (ii) −x+1, −y+1, −z+1.
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O4—H4···O20.95 (4)1.55 (4)2.504 (2)178 (3)
O1—H1···O30.94 (4)1.56 (4)2.499 (2)179 (4)
Table 1
Hydrogen-bond geometry (Å, °)
top
D—H···AD—HH···AD···AD—H···A
O4—H4···O20.95 (4)1.55 (4)2.504 (2)178 (3)
O1—H1···O30.94 (4)1.56 (4)2.499 (2)179 (4)
Acknowledgements top

The authors thank L. Langner for technical support.

references
References top

Brandenburg, K. (2001). DIAMOND. Version 2.1e. Crystal Impact GbR, Bonn, Germany.

Bruckmann, J., Krüger, C., Lehmann, C. W., Leitner, W., Rust, J. & Six, C. (1999). Acta Cryst. C55, 695–696.

Etter, M. C., MacDonald, J. C. & Bernstein, J. (1990). Acta Cryst. B46, 256–262.

Sheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of Göttingen, Germany.

Sicken, M., Weferling, N. & Schmitz, H.-P. (2000). Patent, Clariant GmbH, Patent No. DE 100 65 051 A1.

Siemens (1989). R3m/V Software. Release 3.2. Siemens Analytical X-ray Instruments Inc., Madison, Wisconsin, USA.