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Acta Crystallogr Sect E Struct Rep Online. 2008 July 1; 64(Pt 7): o1178–o1179.
Published online 2008 June 7. doi:  10.1107/S1600536808015675
PMCID: PMC2961726

Ethyl [(2-hydroxy­phen­yl)(pyridinium-2-ylamino)meth­yl]phospho­nate methanol solvate

Abstract

In the title compound, C14H17N2O4P·CH3OH, the planes of the pyridinium-2-ylamino and 2-hydroxy­phenyl groups form a dihedral angle of 75.6 (1)°, with the pyridinium NH group and the 2-hydroxy­phenyl OH group pointing in opposite directions. Three intra­molecular hydrogen bonds are observed. Two phospho­nate and two methanol mol­ecules are connected by O—H(...)O hydrogen bonds as a centrosymmetric dimeric cluster, and inter­act further with other dimeric clusters via N—H(...)O, O—H(...)O and C—H(...)O hydrogen bonds and C—H(...)π inter­actions, resulting in a sheet structure.

Related literature

For related literature, see: Bernstein et al. (1995 [triangle]); Briceño et al. (2007 [triangle]); Foster & Weinhold (1980 [triangle]); Jeffrey et al. (1985 [triangle]); Kaboudin & Moradi (2005 [triangle]); Kachkovskyi & Kolodiazhnyi (2007 [triangle]); Kafarski & Lejczak (2001 [triangle]); Liu et al. (2002 [triangle]); Meyer et al. (2004 [triangle]); Palacios et al. (2005 [triangle]); Rohovec et al. (1999 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-64-o1178-scheme1.jpg

Experimental

Crystal data

  • C14H17N2O4P·CH4O
  • M r = 340.31
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-64-o1178-efi1.jpg
  • a = 12.821 (3) Å
  • b = 9.536 (2) Å
  • c = 16.567 (3) Å
  • β = 122.308 (14)°
  • V = 1711.9 (6) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.19 mm−1
  • T = 298 (2) K
  • 0.40 × 0.20 × 0.20 mm

Data collection

  • Bruker SMART 1K CCD diffractometer
  • Absorption correction: multi-scan (SADABS; Sheldrick, 2000 [triangle]) T min = 0.875, T max = 0.964
  • 6784 measured reflections
  • 2991 independent reflections
  • 2419 reflections with I > 2σ(I)
  • R int = 0.034

Refinement

  • R[F 2 > 2σ(F 2)] = 0.067
  • wR(F 2) = 0.147
  • S = 1.14
  • 2991 reflections
  • 210 parameters
  • 1 restraint
  • H-atom parameters constrained
  • Δρmax = 0.34 e Å−3
  • Δρmin = −0.34 e Å−3

Data collection: SMART (Bruker, 2000 [triangle]); cell refinement: SAINT (Bruker, 2000 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: SHELXTL/PC (Sheldrick, 2008 [triangle]); software used to prepare material for publication: PLATON (Spek, 2003 [triangle]) and publCIF (Westrip, 2008 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536808015675/cf2201sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536808015675/cf2201Isup2.hkl

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

Acknowledgments

The authors acknowledge financial support from the National Natural Science Foundation of China (grant No. 20471033), the Natural Science Foundation of Shanxi Province of China (grant No. 20051013) and the Overseas Returned Scholar Foundation of Shanxi Province of China in 2006.

supplementary crystallographic information

Comment

Organophosphorus compounds are of importance because of their growing applications in medicine and agriculture. Aminophosphonates, one family of organophosphorus compounds, have received much attention as phosphorus analogs of naturally occurring aminocarboxylic acids. Many of these types of compounds have antibacterial, anticancer, and enzyme inhibitory properties, and so on (Kafarski & Lejczak, 2001; Liu et al., 2002; Meyer et al., 2004). Many new aminophosphonate compounds have been synthesized and characterized (Palacios et al., 2005; Kaboudin & Moradi, 2005; Kachkovskyi & Kolodiazhnyi, 2007) for these reasons. The title compound was synthesized in order to understand its inhibitory activity on the protein tyrosine phosphatase 1B (PTP1B). Here we describe the crystal structure.

The planes of the pyridinium-2-amino and 2-hydroxyphenyl groups form a dihedral angle of 75.6 (1)°, with the N—H group of pyridinium and O—H of 2-hydroxyphenyl pointing in opposite directions. When the ethyl group and one of the two O atoms bonded to P are substituted by phenyl groups, the dihedral angle between the 2-hydroxyphenyl and pyridine rings is 54.9 (1)°, and the N atom of the pyridine ring and O—H of 2-hydroxyphenyl are close together, forming an intramolecular hydrogen bond (Rohovec et al., 1999). Thus the substitution of functional groups around the P atom influences the arrangement of other function groups. The ethyl (2-hydroxyphenyl)(pyridinium-2-ylamino)methylphosphonate molecule displays three intramolecular hydrogen bonds, two C—H···O and one N—H···O. N1—H1···O3 and C7—H7···O1 lead to the formation of five-membered S(5) ring motifs (Bernstein et al., 1995; Briceño et al., 2007). C9—H9···O1 results in an eight-membered S(8) ring motif. Thus, O1 is involved in a bifurcated hydrogen bond (Jeffrey et al., 1985), which produces a distorted seven-membered ring. Additionally, the solvent methanol is hydrogen bonded to O4, stabilizing the molecular conformation.

The intermolecular interactions of compound (I) are shown in Fig. 2 and in the hydrogen bonding table. Two ethyl (2-hydroxyphenyl)(pyridinium-2-ylamino)methylphosphonate molecules are connected antiparallel as a centrosymmetric dimer via bifurcated hydrogen bonds in which N1 and N2 are donors and O3 is the acceptor, giving rise to two hydrogen-bonded R12(6) rings. In the bifurcated hydrogen bond, the two interactions are unequal; the N···O distance of 2.694 (3) Å and angle of 161° are obviously a stronger interaction than the N···O distance of 2.813 (3) Å and the angle of 150°. Two intermolecular N—H···O hydrogen bonds together with two intramolecular N—H···O interactions form another R44(4) ring. The methanol molecules also link the dimers through O—H···O and C—H···O hydrogen bonds, generating two R33(9) rings. Thus five hydrogen-bonded rings, namely two R33(9), two R12(6) and one R44(4), form a complicated hydrogen-bonding network (Fig. 2). In this network, O3 acts as an acceptor of three hydrogen atoms and forms a trifurcated hydrogen bond (Jeffrey et al., 1985), which is not observed very often. Meanwhile, O3 and one of its equivalents by symmetry share H1A, forming a bifurcated hydrogen bond. Neighbouring dimers are linked to each other via O—H···O hydrogen bonds. Four such dimers constitute a repeat unit with a thirty-four-membered R66(34) ring, generating two-dimensional sheets parallel to (102). A C—H···π weak interaction involving ethyl and hydroxyphenyl groups also helps to stabilize the crystal structure (Fig. 2).

Experimental

A solution of 1.882 g (0.02 mol) pyridin-2-amine in 20 ml of ethanol was added dropwise to a stirred solution of an equimolar amount of salicyaldehyde (0.02 mol, 3.1 ml) in 20 ml of ethanol and refluxed for 2 h. A solution of diethyl phosphonate (0.04 mol, 5.13 ml) in 10 ml of ethanol was then added dropwise. The mixture was refluxed for about 30 h until a solid appeared. The precipitate was collected and washed with ethanol and diethyl ether. A white solid was obtained (2.107 g, yield 34.4%). Colorless crystals were obtained from methanol.

Refinement

The C13—C14 bond length was restrained to 1.50 (1) Å, because free refinement gave an unacceptably short bond, possibly due to unresolved disorder. H atoms attached to C atoms of (I) were placed in geometrically idealized positions with Csp2—H = 0.93, Csp3(methyl)—H = 0.96, and Csp3(methylene)—H = 0.97 Å and constrained to ride on their parent atoms, with Uiso(H) = 1.2Ueq(C) (1.5Ueqfor methyl H). H atoms attached to N and O atoms were located in a difference Fourier map and refined as riding, with Uiso = 1.2Ueq(N,O).

Figures

Fig. 1.
The molecular structure of (I) with displacement ellipsoids drawn at the 30% probability level. Dotted lines indicate intramolecular hydrogen bonds.
Fig. 2.
The dimer formed via R44(4), R12(6) and R33(9) rings, and the two-dimensional sheet formed through R66(34) rings. Dotted lines indicate hydrogen bonds and C—H···π interactions.

Crystal data

C14H17N2O4P·CH4OF000 = 720
Mr = 340.31Dx = 1.320 Mg m3
Monoclinic, P21/cMo Kα radiation λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 1906 reflections
a = 12.821 (3) Åθ = 2.5–23.8º
b = 9.536 (2) ŵ = 0.19 mm1
c = 16.567 (3) ÅT = 298 (2) K
β = 122.308 (14)ºBlock, colourless
V = 1711.9 (6) Å30.40 × 0.20 × 0.20 mm
Z = 4

Data collection

Bruker SMART 1K CCD diffractometer2991 independent reflections
Radiation source: fine-focus sealed tube2419 reflections with I > 2σ(I)
Monochromator: graphiteRint = 0.034
T = 298(2) Kθmax = 25.0º
ω scansθmin = 1.9º
Absorption correction: multi-scan(SADABS; Sheldrick, 2000)h = −15→15
Tmin = 0.875, Tmax = 0.964k = −11→8
6784 measured reflectionsl = −17→19

Refinement

Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.067H-atom parameters constrained
wR(F2) = 0.147  w = 1/[σ2(Fo2) + (0.052P)2 + 1.1778P] where P = (Fo2 + 2Fc2)/3
S = 1.14(Δ/σ)max = 0.001
2991 reflectionsΔρmax = 0.34 e Å3
210 parametersΔρmin = −0.34 e Å3
1 restraintExtinction correction: none
Primary atom site location: structure-invariant direct methods

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
P10.75798 (7)0.45914 (9)0.40161 (6)0.0359 (3)
O10.5572 (2)0.7872 (3)0.22842 (16)0.0561 (7)
H10.50070.84240.19640.067*
O20.7741 (2)0.3583 (3)0.33273 (18)0.0578 (7)
O30.86639 (19)0.4487 (2)0.50109 (15)0.0466 (6)
O40.63500 (19)0.4400 (2)0.38884 (15)0.0481 (6)
N10.8906 (2)0.6464 (3)0.37455 (17)0.0390 (7)
H1A0.95210.60230.42210.047*
N21.0392 (2)0.7331 (3)0.35182 (17)0.0381 (6)
H2A1.08520.67750.39960.046*
C10.6172 (3)0.8248 (3)0.3218 (2)0.0417 (8)
C20.5805 (3)0.9373 (4)0.3538 (3)0.0552 (10)
H20.51150.98930.31050.066*
C30.6448 (4)0.9723 (4)0.4481 (3)0.0681 (12)
H30.61901.04750.46900.082*
C40.7468 (4)0.8976 (5)0.5121 (3)0.0713 (12)
H40.79050.92150.57650.086*
C50.7848 (3)0.7865 (4)0.4808 (2)0.0545 (10)
H50.85490.73640.52460.065*
C60.7210 (3)0.7479 (3)0.3857 (2)0.0373 (7)
C70.7639 (3)0.6274 (3)0.3523 (2)0.0352 (7)
H70.70910.62170.28270.042*
C80.9195 (3)0.7286 (3)0.3241 (2)0.0336 (7)
C90.8361 (3)0.8096 (3)0.2451 (2)0.0415 (8)
H90.75300.81190.22490.050*
C100.8774 (3)0.8845 (4)0.1985 (2)0.0531 (10)
H100.82190.93790.14570.064*
C111.0008 (4)0.8832 (4)0.2277 (3)0.0559 (10)
H111.02820.93410.19460.067*
C121.0803 (3)0.8069 (4)0.3050 (3)0.0479 (9)
H121.16370.80510.32600.057*
C130.7568 (5)0.2100 (5)0.3340 (4)0.0900 (15)
H13A0.71220.17600.26870.108*
H13B0.70550.19310.35980.108*
C140.8694 (6)0.1287 (6)0.3889 (5)0.126 (2)
H14A0.91710.13630.36000.189*
H14B0.84890.03220.38990.189*
H14C0.91650.16400.45300.189*
O50.6628 (3)0.3431 (4)0.5586 (2)0.0890 (10)
H5A0.65140.37280.50800.107*
C150.5492 (6)0.3157 (8)0.5475 (5)0.125 (2)
H15A0.48960.29400.48180.187*
H15B0.52260.39670.56610.187*
H15C0.55710.23750.58680.187*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
P10.0292 (4)0.0369 (5)0.0371 (5)−0.0019 (4)0.0146 (4)0.0050 (4)
O10.0374 (13)0.0611 (17)0.0480 (15)0.0195 (12)0.0082 (11)0.0025 (12)
O20.0709 (17)0.0395 (14)0.0736 (17)−0.0025 (12)0.0458 (15)−0.0012 (12)
O30.0325 (12)0.0521 (15)0.0422 (13)0.0002 (10)0.0113 (10)0.0174 (11)
O40.0320 (12)0.0570 (15)0.0480 (13)−0.0098 (11)0.0164 (11)−0.0010 (11)
N10.0282 (13)0.0438 (16)0.0367 (14)0.0043 (12)0.0117 (12)0.0146 (12)
N20.0345 (14)0.0380 (15)0.0376 (15)0.0027 (12)0.0165 (12)0.0066 (12)
C10.0335 (17)0.0407 (19)0.048 (2)−0.0008 (15)0.0203 (16)0.0013 (16)
C20.052 (2)0.044 (2)0.071 (3)0.0119 (17)0.034 (2)0.0047 (19)
C30.087 (3)0.051 (3)0.077 (3)0.009 (2)0.050 (3)−0.012 (2)
C40.094 (3)0.060 (3)0.053 (2)−0.001 (2)0.035 (2)−0.013 (2)
C50.059 (2)0.049 (2)0.044 (2)0.0051 (18)0.0207 (18)0.0018 (17)
C60.0353 (17)0.0355 (18)0.0393 (18)−0.0013 (14)0.0188 (15)0.0040 (14)
C70.0259 (15)0.0401 (18)0.0308 (16)0.0009 (13)0.0093 (13)0.0038 (13)
C80.0355 (17)0.0302 (16)0.0327 (16)0.0000 (13)0.0165 (14)0.0021 (13)
C90.0400 (18)0.045 (2)0.0394 (18)0.0051 (15)0.0210 (15)0.0112 (15)
C100.061 (2)0.052 (2)0.043 (2)0.0107 (19)0.0250 (18)0.0176 (17)
C110.066 (3)0.052 (2)0.065 (2)0.001 (2)0.045 (2)0.0142 (19)
C120.047 (2)0.047 (2)0.059 (2)−0.0012 (17)0.0350 (19)0.0043 (18)
C130.100 (4)0.048 (3)0.121 (4)−0.006 (3)0.059 (3)−0.009 (3)
C140.135 (5)0.074 (4)0.176 (6)0.008 (4)0.088 (5)0.001 (4)
O50.073 (2)0.127 (3)0.0708 (19)0.0061 (19)0.0411 (17)0.0241 (19)
C150.113 (5)0.144 (6)0.158 (6)−0.003 (4)0.099 (5)0.024 (5)

Geometric parameters (Å, °)

P1—O41.486 (2)C5—H50.930
P1—O31.486 (2)C6—C71.502 (4)
P1—O21.588 (3)C7—H70.980
P1—C71.821 (3)C8—C91.399 (4)
O1—C11.357 (4)C9—C101.351 (4)
O1—H10.820C9—H90.930
O2—C131.433 (5)C10—C111.386 (5)
N1—C81.334 (4)C10—H100.930
N1—C71.473 (4)C11—C121.347 (5)
N1—H1A0.869C11—H110.930
N2—C81.347 (4)C12—H120.930
N2—C121.347 (4)C13—C141.451 (6)
N2—H2A0.870C13—H13A0.970
C1—C21.385 (5)C13—H13B0.970
C1—C61.387 (4)C14—H14A0.960
C2—C31.363 (5)C14—H14B0.960
C2—H20.930C14—H14C0.960
C3—C41.364 (6)O5—C151.391 (6)
C3—H30.930O5—H5A0.821
C4—C51.378 (5)C15—H15A0.960
C4—H40.930C15—H15B0.960
C5—C61.381 (4)C15—H15C0.960
O4—P1—O3116.22 (13)C6—C7—H7107.7
O4—P1—O2111.04 (14)P1—C7—H7107.7
O3—P1—O2110.63 (14)N1—C8—N2116.9 (3)
O4—P1—C7109.88 (14)N1—C8—C9125.5 (3)
O3—P1—C7108.56 (13)N2—C8—C9117.6 (3)
O2—P1—C799.12 (14)C10—C9—C8119.3 (3)
C1—O1—H1109.5C10—C9—H9120.4
C13—O2—P1120.4 (3)C8—C9—H9120.4
C8—N1—C7123.6 (2)C9—C10—C11121.3 (3)
C8—N1—H1A115.6C9—C10—H10119.3
C7—N1—H1A120.8C11—C10—H10119.3
C8—N2—C12123.1 (3)C12—C11—C10118.6 (3)
C8—N2—H2A112.8C12—C11—H11120.7
C12—N2—H2A123.9C10—C11—H11120.7
O1—C1—C2122.6 (3)N2—C12—C11120.0 (3)
O1—C1—C6117.3 (3)N2—C12—H12120.0
C2—C1—C6120.1 (3)C11—C12—H12120.0
C3—C2—C1120.5 (4)O2—C13—C14115.2 (4)
C3—C2—H2119.7O2—C13—H13A108.5
C1—C2—H2119.7C14—C13—H13A108.5
C2—C3—C4120.2 (4)O2—C13—H13B108.5
C2—C3—H3119.9C14—C13—H13B108.5
C4—C3—H3119.9H13A—C13—H13B107.5
C3—C4—C5119.7 (4)C13—C14—H14A109.5
C3—C4—H4120.2C13—C14—H14B109.5
C5—C4—H4120.2H14A—C14—H14B109.5
C4—C5—C6121.4 (4)C13—C14—H14C109.5
C4—C5—H5119.3H14A—C14—H14C109.5
C6—C5—H5119.3H14B—C14—H14C109.5
C5—C6—C1118.1 (3)C15—O5—H5A109.1
C5—C6—C7120.9 (3)O5—C15—H15A109.5
C1—C6—C7120.9 (3)O5—C15—H15B109.5
N1—C7—C6112.7 (3)H15A—C15—H15B109.5
N1—C7—P1107.5 (2)O5—C15—H15C109.5
C6—C7—P1113.4 (2)H15A—C15—H15C109.5
N1—C7—H7107.7H15B—C15—H15C109.5
O4—P1—O2—C13−55.0 (3)C1—C6—C7—P1−116.5 (3)
O3—P1—O2—C1375.6 (3)O4—P1—C7—N1174.96 (19)
C7—P1—O2—C13−170.5 (3)O3—P1—C7—N146.9 (2)
O1—C1—C2—C3−179.0 (3)O2—P1—C7—N1−68.6 (2)
C6—C1—C2—C3−0.9 (5)O4—P1—C7—C649.7 (2)
C1—C2—C3—C40.6 (6)O3—P1—C7—C6−78.4 (2)
C2—C3—C4—C50.1 (7)O2—P1—C7—C6166.1 (2)
C3—C4—C5—C6−0.6 (6)C7—N1—C8—N2−178.6 (3)
C4—C5—C6—C10.3 (5)C7—N1—C8—C91.3 (5)
C4—C5—C6—C7179.4 (3)C12—N2—C8—N1177.1 (3)
O1—C1—C6—C5178.6 (3)C12—N2—C8—C9−2.7 (5)
C2—C1—C6—C50.4 (5)N1—C8—C9—C10−177.7 (3)
O1—C1—C6—C7−0.5 (4)N2—C8—C9—C102.1 (5)
C2—C1—C6—C7−178.7 (3)C8—C9—C10—C11−0.4 (5)
C8—N1—C7—C6−78.5 (4)C9—C10—C11—C12−0.9 (6)
C8—N1—C7—P1155.8 (2)C8—N2—C12—C111.5 (5)
C5—C6—C7—N1−58.0 (4)C10—C11—C12—N20.4 (6)
C1—C6—C7—N1121.0 (3)P1—O2—C13—C14−99.2 (5)
C5—C6—C7—P164.4 (4)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
N1—H1A···O30.872.572.957 (3)108
N2—H2A···O3i0.871.862.692 (3)160
N1—H1A···O3i0.872.032.813 (3)150
O1—H1···O4ii0.821.812.618 (3)170
C7—H7···O10.982.282.783 (4)111
C9—H9···O10.932.553.438 (5)160
C12—H12···O5i0.932.463.169 (5)133
O5—H5A···O40.821.982.795 (4)176
C14—H14B···Cgiii0.962.913.697 (8)141

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

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: CF2201).

References

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