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Acta Crystallogr Sect E Struct Rep Online. 2010 November 1; 66(Pt 11): o2823–o2824.
Published online 2010 October 20. doi:  10.1107/S1600536810040304
PMCID: PMC3009303

(R)-(1-Ammonio­prop­yl)phospho­nate

Abstract

The title compound, C3H10NO3P, crystallizes in its zwitterionic form, H3N+CH(C2H5)PO(O)(OH), with the asymmetric unit being composed by two of such entities (Z′ = 2). The crystal packing leads to a sequence of hydro­phobic and hydro­philic layers. While the hydro­phobic layer comprises the aliphatic substituent groups, the hydro­philic one is held together by a series of strong and rather directional N+—H(...)O and O—H(...)O hydrogen bonds.

Related literature

For a description of the graph-set notation for hydrogen-bonded aggregates, see: Grell et al. (1999 [triangle]). For basic stereochemistry terminology, see: Moss (1996 [triangle]). For the biological activity of the title compound, see: Hudson & Ismail (2001 [triangle]). For the crystal structure of a racemic mixture containing the title compound, see: Bashall et al. (2010 [triangle]). For previous work from our research group on the assembly of coordination polymers using phospho­nic-based mol­ecules, see: Cunha-Silva, Ananias et al. (2009 [triangle]); Cunha-Silva, Lima et al. (2009 [triangle]); Cunha-Silva et al. (2007 [triangle]); Rocha et al. (2009 [triangle]); Shi, Cunha-Silva et al. (2008 [triangle]); Shi, Trindade et al. (2008 [triangle]). For a related structure, see: Fernandes et al. (2010 [triangle]). For a description of the TOPOS software, see: Blatov & Proserpio (2009 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-66-o2823-scheme1.jpg

Experimental

Crystal data

  • C3H10NO3P
  • M r = 139.09
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-o2823-efi1.jpg
  • a = 9.3988 (13) Å
  • b = 6.2511 (8) Å
  • c = 10.8575 (15) Å
  • β = 105.731 (9)°
  • V = 614.02 (14) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.37 mm−1
  • T = 150 K
  • 0.16 × 0.08 × 0.02 mm

Data collection

  • Bruker X8 Kappa CCD APEXII diffractometer
  • Absorption correction: multi-scan (SADABS; Sheldrick, 1998 [triangle]) T min = 0.943, T max = 0.993
  • 23447 measured reflections
  • 4196 independent reflections
  • 3465 reflections with I > 2σ(I)
  • R int = 0.053

Refinement

  • R[F 2 > 2σ(F 2)] = 0.042
  • wR(F 2) = 0.088
  • S = 1.06
  • 4196 reflections
  • 171 parameters
  • 15 restraints
  • H atoms treated by a mixture of independent and constrained refinement
  • Δρmax = 0.38 e Å−3
  • Δρmin = −0.55 e Å−3
  • Absolute structure: Flack (1983 [triangle]), 1730 Friedel pairs
  • Flack parameter: −0.03 (8)

Data collection: APEX2 (Bruker, 2006 [triangle]); cell refinement: SAINT-Plus (Bruker, 2005 [triangle]); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXTL; molecular graphics: DIAMOND (Brandenburg, 2009 [triangle]); software used to prepare material for publication: SHELXTL.

Table 1
Selected torsion angles (°)
Table 2
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810040304/pk2268sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810040304/pk2268Isup2.hkl

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

Acknowledgments

We are grateful to the Fundação para a Ciência e a Tecnologia (FCT, Portugal) for their general financial support (R&D project PTDC/QUI-QUI/098098/2008), for the post-doctoral and PhD research grants Nos. SFRH/BPD/63736/2009 (to JAF) and SFRH/BD/66371/2009 (to SMFV), and for specific funding toward the purchase of the diffractometer.

supplementary crystallographic information

Comment

The racemic mixture of the title compound is known as Ampropylfos and has been the object of several studies for its use as a pesticide (Hudson & Ismail, 2001), and its crystal structure has been very recently reported (Bashall et al., 2010). Following our interest in the use of phosphonic acid molecules (Fernandes et al., 2010; Cunha-Silva, Ananias et al., 2009; Cunha-Silva, Lima et al., 2009; Rocha et al., 2009; Shi, Cunha-Silva et al., 2008; Shi, Trindade et al., 2008; Cunha-Silva et al., 2007) here we wish to describe the crystal structure of the title compound (see Scheme).

The asymmetric unit is composed by two entities of the title compound in their zwitterionic form, in which the acidic phosphonate moiety donates one proton to the amino group (Figure 1). The geometrical conformations of the two molecules are considerably different: in one unit the two torsion angles O3—P1—C1—C2 and P1—C1—C2—C3 are both +synclinal and in the other the analogous torsion angles (O6—P2—C4—C5 and P2—C4—C5—C6) are -synclinal and antiperiplanar, respectively (see Table 1; Moss, 1996). The two crystallographically unique molecules are organized in the crystal structure into a supramolecular bilayer (in the ab plane) having the hydrophilic portion in the interior (composed by the amino, methyne and phosphonate moieties) and the hydrophobic in the outer position (formed by the pendant —CH2CH3 groups) (Figures 2 and 3).

Inside the hydrophilic section, individual functional groups are disposed in a zigzag fashion along the [010] direction of the unit cell, leading to the formation of a supramolecular chain held together by a combination of four N+—H···O hydrogen bridges (green dashed bonds in Figure 2; Table 2) - graph set motif R34(10) (Grell et al., 1999). Supramolecular chains are, in turn, interconnected in the ab plane via the remanant N+—H···O (orange dashed lines in Figure 2) and O—H···O hydrogen bonds (violet dashed lines in Figure 2).

Noteworthy, all hydrogen bonding interactions are rather strong with the internuclear D···A distances ranging from 2.583 (2) to 2.914 (2) Å. In addition, the left angle bracket(DHA) angles range from ca 144 to 177°. One acceptor atom (O4) participates in a D13(7) graph set motif with all left angle bracket(DHA) greater than ca 150°. Other acceptors (O1 and O2) are, in turn, involved in D12(5) motifs: N1—H2···O2 with left angle bracket(DHA) of ca 144° and the other three interactions having angles larger than ca 171°. O5 is the only acceptor in a S11 graph set motif: N2—H5···O5 with left angle bracket(DHA) of ca 162° (See Table 2).

The crystal can be better described by employing a topological approach for the description of the aforementioned hydrogen bonding interactions. Taking the geometrical centre of each molecular unit as a node, and being the hydrogen bonding interactions the connections between nodes, the structure can be simplified into a two-dimensional uninodal 7-connected single-penetrated planar (4,4)IIIb network, with total Schläfli symbol 36.412.53 (Blatov & Proserpio, 2009).

Experimental

The title compound was purchased from Sigma-Aldrich (Aldrich, 98%) and was used as received without purification. Suitable single crystals were grown from an aqueous solution over a period of one month.

1H-NMR (300.13 MHz, D2O) δ: 0.91 (t, 3H, J(1H-1H) = 7.5 Hz, CH3), 1.56–1.63 and 1.75–1.86 (2 m, 2H, CH2) and 2.96–3.05 (m, 1H, CH).

13C-NMR (75.47 MHz, D2O) δ: 13.0 (d, J(13C-31P) = 9.7 Hz, CH3), 24.7 (d, J(13C-31P)= 1.6 Hz, CH2) and 53.5 (d, J(13C-31P)= 143.3 Hz, CH).

31P-NMR (121.49 MHz, D2O) δ: 14.1 (dt, J(31P-1H)= 12.1 and 23.1 Hz).

Refinement

Hydrogen atoms bound to carbon were included in the final structural model using a riding-motion approximation with C—H = 1.00 Å (tertiary C—H), 0.99 Å (—CH2) or 0.98 Å (terminal —CH3). The isotropic thermal displacement parameters for these atoms were fixed at 1.2 (for the two former families) or 1.5 (for the terminal methyl group) times Ueq of the respective parent atom.

Hydrogen atoms associated with the protonated —NH3+ group or the pendant —OH moiety were directly located in difference Fourier maps and were included in the final structural model with the distances restrained to 0.95 (1) Å and Uiso=1.5×Ueq of the respective parent atom. The H···H distances of the —NH3+ terminal group have been further restrained to 1.55 (1) Å in order to ensure a chemically reasonable geometry.

A total of 1730 estimated Friedel pairs have not been merged and were used as independent data for the structure refinement. The Flack parameter (Flack, 1983) converged to -0.03 (8), ultimately assuring a valid absolute structure determination from the single-crystal data set.

Figures

Fig. 1.
Asymmetric unit of the title compound showing the two crystallographically indenpendent molecular units. Thermal ellipsoids are drawn at the 80% probability level and the atomic labeling is provided for all non-hydrogen atoms. Hydrogen atoms are represented ...
Fig. 2.
Portion of the supramolecular bilayer showing the one-dimensional zigzag chain running parallel to the [010] direction of the unit cell (graph set motif R34(10) - dashed green lines) which is interconnected by the inter-chain O—H···O ...
Fig. 3.
Crystal packing of the title compound viewed in perspective along the (a) [100] and (b) [001] directions of the unit cell. Hydrogen bonds are represented as dashed green (intra-chain N+—H···O), violet (inter-chain O—H···O) ...

Crystal data

C3H10NO3PF(000) = 296
Mr = 139.09Dx = 1.505 Mg m3
Monoclinic, P21Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ybCell parameters from 6291 reflections
a = 9.3988 (13) Åθ = 2.3–32.1°
b = 6.2511 (8) ŵ = 0.37 mm1
c = 10.8575 (15) ÅT = 150 K
β = 105.731 (9)°Plate, colourless
V = 614.02 (14) Å30.16 × 0.08 × 0.02 mm
Z = 4

Data collection

Bruker X8 Kappa CCD APEXII diffractometer4196 independent reflections
Radiation source: fine-focus sealed tube3465 reflections with I > 2σ(I)
graphiteRint = 0.053
ω and [var phi] scansθmax = 33.1°, θmin = 3.8°
Absorption correction: multi-scan (SADABS; Sheldrick, 1998)h = −14→14
Tmin = 0.943, Tmax = 0.993k = −7→9
23447 measured reflectionsl = −16→16

Refinement

Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.042H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.088w = 1/[σ2(Fo2) + (0.0396P)2 + 0.1217P] where P = (Fo2 + 2Fc2)/3
S = 1.06(Δ/σ)max = 0.001
4196 reflectionsΔρmax = 0.38 e Å3
171 parametersΔρmin = −0.55 e Å3
15 restraintsAbsolute structure: Flack (1983), 1730 Friedel pairs
Primary atom site location: structure-invariant direct methodsFlack parameter: −0.03 (8)

Special details

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)

xyzUiso*/Ueq
P10.17626 (5)0.89317 (8)0.65337 (5)0.01280 (11)
O10.29018 (16)0.7215 (2)0.69950 (15)0.0197 (3)
O20.10172 (14)0.8923 (3)0.51232 (13)0.0182 (3)
O30.06166 (16)0.8928 (3)0.73443 (14)0.0272 (4)
H3D−0.0346 (16)0.837 (4)0.707 (3)0.041*
N10.1977 (2)1.3190 (3)0.60484 (18)0.0159 (4)
H10.231 (2)1.455 (2)0.6360 (19)0.024*
H20.0945 (11)1.307 (4)0.595 (2)0.024*
H30.217 (2)1.294 (4)0.5245 (13)0.024*
C10.2726 (2)1.1499 (4)0.69718 (19)0.0162 (4)
H1A0.37421.13200.68630.019*
C20.2910 (3)1.2237 (4)0.8348 (2)0.0218 (5)
H2A0.33401.36930.84530.026*
H2B0.19241.23170.85090.026*
C30.3897 (3)1.0758 (4)0.9338 (2)0.0248 (5)
H3A0.34380.93410.92870.037*
H3B0.40211.13511.01960.037*
H3C0.48651.06310.91670.037*
P20.64788 (6)0.66572 (8)0.65107 (5)0.01273 (11)
O40.78570 (16)0.7909 (2)0.65226 (15)0.0177 (3)
O50.54723 (16)0.6182 (2)0.52207 (13)0.0180 (3)
O60.57135 (16)0.7875 (2)0.74254 (14)0.0169 (3)
H6A0.4679 (11)0.771 (5)0.725 (2)0.025*
N20.71494 (19)0.2456 (3)0.63228 (17)0.0144 (4)
H40.744 (2)0.109 (2)0.6697 (19)0.022*
H50.6217 (12)0.230 (3)0.5709 (16)0.022*
H60.7853 (16)0.289 (3)0.5885 (18)0.022*
C40.6989 (2)0.4063 (3)0.72982 (18)0.0133 (4)
H4A0.61490.35880.76340.016*
C50.8369 (2)0.4151 (4)0.8428 (2)0.0208 (4)
H5A0.82690.53510.89940.025*
H5B0.92370.44490.81030.025*
C60.8649 (3)0.2079 (4)0.9217 (2)0.0298 (6)
H6B0.77460.16660.94430.045*
H6C0.94480.23120.99990.045*
H6D0.89320.09380.87110.045*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
P10.0114 (2)0.0102 (2)0.0176 (2)−0.0005 (2)0.00522 (17)−0.0016 (2)
O10.0169 (7)0.0114 (8)0.0292 (8)0.0003 (6)0.0034 (6)0.0005 (6)
O20.0167 (6)0.0171 (7)0.0207 (7)−0.0024 (7)0.0049 (5)−0.0027 (7)
O30.0165 (7)0.0427 (10)0.0238 (8)−0.0090 (9)0.0079 (6)−0.0080 (9)
N10.0193 (9)0.0098 (8)0.0178 (9)0.0005 (7)0.0035 (7)−0.0007 (7)
C10.0172 (9)0.0099 (9)0.0200 (10)0.0010 (8)0.0025 (7)0.0007 (8)
C20.0295 (12)0.0170 (11)0.0175 (10)−0.0027 (9)0.0040 (9)−0.0034 (8)
C30.0323 (13)0.0226 (12)0.0177 (11)−0.0008 (10)0.0037 (9)−0.0007 (9)
P20.0117 (2)0.0087 (2)0.0174 (2)0.0009 (2)0.00322 (18)0.0000 (2)
O40.0141 (7)0.0133 (7)0.0261 (8)−0.0006 (6)0.0063 (6)−0.0003 (6)
O50.0214 (8)0.0124 (8)0.0173 (7)0.0038 (6)0.0002 (6)−0.0011 (6)
O60.0162 (7)0.0130 (7)0.0212 (8)0.0013 (6)0.0046 (6)−0.0041 (6)
N20.0155 (8)0.0094 (8)0.0163 (9)0.0010 (7)0.0006 (7)−0.0016 (7)
C40.0142 (8)0.0090 (9)0.0164 (8)0.0006 (8)0.0034 (7)−0.0028 (8)
C50.0195 (10)0.0186 (12)0.0203 (10)0.0030 (9)−0.0014 (8)−0.0004 (10)
C60.0359 (13)0.0264 (14)0.0217 (11)0.0088 (10)−0.0015 (10)0.0037 (9)

Geometric parameters (Å, °)

P1—O21.5014 (15)P2—O51.4921 (15)
P1—O11.5029 (15)P2—O41.5105 (15)
P1—O31.5649 (15)P2—O61.5718 (16)
P1—C11.841 (2)P2—C41.836 (2)
O3—H3D0.939 (10)O6—H6A0.944 (10)
N1—C11.495 (3)N2—C41.496 (3)
N1—H10.939 (9)N2—H40.952 (9)
N1—H20.950 (9)N2—H50.951 (9)
N1—H30.950 (9)N2—H60.953 (9)
C1—C21.528 (3)C4—C51.525 (3)
C1—H1A1.0000C4—H4A1.0000
C2—C31.527 (3)C5—C61.536 (3)
C2—H2A0.9900C5—H5A0.9900
C2—H2B0.9900C5—H5B0.9900
C3—H3A0.9800C6—H6B0.9800
C3—H3B0.9800C6—H6C0.9800
C3—H3C0.9800C6—H6D0.9800
O2—P1—O1115.51 (9)O5—P2—O4115.80 (9)
O2—P1—O3111.82 (8)O5—P2—O6114.03 (8)
O1—P1—O3110.39 (10)O4—P2—O6106.37 (9)
O2—P1—C1109.12 (9)O5—P2—C4106.28 (8)
O1—P1—C1106.29 (9)O4—P2—C4109.81 (9)
O3—P1—C1102.78 (10)O6—P2—C4103.89 (8)
P1—O3—H3D124.9 (18)P2—O6—H6A116.1 (16)
C1—N1—H1110.3 (14)C4—N2—H4111.8 (14)
C1—N1—H2107.5 (15)C4—N2—H5108.2 (14)
H1—N1—H2110.3 (12)H4—N2—H5108.1 (12)
C1—N1—H3109.2 (14)C4—N2—H6112.1 (14)
H1—N1—H3110.3 (12)H4—N2—H6108.3 (12)
H2—N1—H3109.2 (12)H5—N2—H6108.1 (11)
N1—C1—C2110.49 (17)N2—C4—C5111.50 (17)
N1—C1—P1109.52 (13)N2—C4—P2109.09 (13)
C2—C1—P1115.69 (16)C5—C4—P2113.58 (15)
N1—C1—H1A106.9N2—C4—H4A107.5
C2—C1—H1A106.9C5—C4—H4A107.5
P1—C1—H1A106.9P2—C4—H4A107.5
C3—C2—C1113.07 (19)C4—C5—C6113.4 (2)
C3—C2—H2A109.0C4—C5—H5A108.9
C1—C2—H2A109.0C6—C5—H5A108.9
C3—C2—H2B109.0C4—C5—H5B108.9
C1—C2—H2B109.0C6—C5—H5B108.9
H2A—C2—H2B107.8H5A—C5—H5B107.7
C2—C3—H3A109.5C5—C6—H6B109.5
C2—C3—H3B109.5C5—C6—H6C109.5
H3A—C3—H3B109.5H6B—C6—H6C109.5
C2—C3—H3C109.5C5—C6—H6D109.5
H3A—C3—H3C109.5H6B—C6—H6D109.5
H3B—C3—H3C109.5H6C—C6—H6D109.5
O2—P1—C1—N126.71 (17)O5—P2—C4—N236.46 (15)
O1—P1—C1—N1151.89 (14)O4—P2—C4—N2−89.49 (14)
O3—P1—C1—N1−92.10 (15)O6—P2—C4—N2157.07 (12)
O2—P1—C1—C2152.35 (15)O5—P2—C4—C5161.50 (14)
O1—P1—C1—C2−82.47 (17)O4—P2—C4—C535.56 (17)
O3—P1—C1—C233.53 (18)O6—P2—C4—C5−77.88 (16)
N1—C1—C2—C3−170.11 (19)N2—C4—C5—C6−65.7 (2)
P1—C1—C2—C364.8 (2)P2—C4—C5—C6170.61 (16)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
O3—H3D···O4i0.94 (1)1.66 (1)2.583 (2)168 (3)
N1—H1···O1ii0.94 (1)1.83 (1)2.767 (2)178 (2)
N1—H2···O2iii0.95 (1)1.97 (2)2.794 (2)144 (2)
N1—H3···O4iv0.95 (1)1.91 (1)2.843 (3)166 (2)
O6—H6A···O10.94 (1)1.65 (1)2.589 (2)175 (3)
N2—H4···O4v0.95 (1)2.05 (2)2.914 (2)151 (2)
N2—H5···O5vi0.95 (1)1.78 (1)2.697 (2)162 (2)
N2—H6···O2vi0.95 (1)1.84 (1)2.783 (2)172 (2)

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

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: PK2268).

References

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