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Acta Crystallogr Sect E Struct Rep Online. 2009 October 1; 65(Pt 10): o2506–o2507.
Published online 2009 September 19. doi:  10.1107/S1600536809037039
PMCID: PMC2970406

Diethyl [(5-chloro-2-hydroxy­anilino)(4-chloro­phen­yl)meth­yl]phospho­nate

Abstract

In the title compound, C17H20Cl2NO4P, the P atom is bonded in a distorted tetra­hedral environment. The dihedral angle between the two benzene rings is 80.5 (1)°. In the crystal structure, inter­molecular O—H(...)O and N—H(...)O hydrogen bonds link pairs of mol­ecules into centrosymmetric dimers. These dimers, are in turn, linked by weak inter­molecular C—H(...)O hydrogen bonds into one-dimensional chains along [010]. Additional stabilization is provided by very weak C—H(...)Cl inter­actions.

Related literature

For applications of α-amino­phospho­nates, see: Allen et al. (1989 [triangle]); Baylis et al. (1984 [triangle]); Fields (1999 [triangle]); Hirschmann et al. (1994 [triangle]); Kafarski & Lejczak (1991 [triangle]); Miliszkiewicz et al. (1992 [triangle]). For the anti­bacterial activity of the title compound, see: Syam Prasad et al. (2007 [triangle]). For related structures, see: Boehlow et al. (1997 [triangle]); Yang et al. (2005 [triangle]); Sawka-Dobrowolska & Kowalik (1985 [triangle]); Sawka-Dobrowolska & Rułko (1987 [triangle]); Sanders et al. (1996 [triangle]); Ezra & Collin (1973 [triangle]). For P—C bond lengths in related structures, see: Rużić-Toroš et al. (1978 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-65-o2506-scheme1.jpg

Experimental

Crystal data

  • C17H20Cl2NO4P
  • M r = 404.21
  • Triclinic, An external file that holds a picture, illustration, etc.
Object name is e-65-o2506-efi1.jpg
  • a = 7.790 (3) Å
  • b = 9.297 (4) Å
  • c = 14.372 (6) Å
  • α = 82.817 (6)°
  • β = 80.842 (6)°
  • γ = 70.323 (6)°
  • V = 964.7 (7) Å3
  • Z = 2
  • Mo Kα radiation
  • μ = 0.44 mm−1
  • T = 294 K
  • 0.25 × 0.25 × 0.13 mm

Data collection

  • Siemens SMART CCD area-detector diffractometer
  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996 [triangle]) T min = 0.896, T max = 0.944
  • 10997 measured reflections
  • 4863 independent reflections
  • 3635 reflections with I > 2σ(I)
  • R int = 0.017

Refinement

  • R[F 2 > 2σ(F 2)] = 0.053
  • wR(F 2) = 0.159
  • S = 1.05
  • 4863 reflections
  • 226 parameters
  • H-atom parameters constrained
  • Δρmax = 0.56 e Å−3
  • Δρmin = −0.34 e Å−3

Data collection: SMART (Bruker 2001 [triangle]); cell refinement: SAINT (Bruker 2002 [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: ZORTEPII (Zsolnai, 1997 [triangle]) and PLATON (Spek, 2009 [triangle]); software used to prepare material for publication: enCIFer (Allen et al., 2004 [triangle]) and PARST (Nardelli, 1995 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809037039/lh2891sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809037039/lh2891Isup2.hkl

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

Acknowledgments

MK thanks the University Grants Commission, New Delhi, for sanctioning the major project for this work.

supplementary crystallographic information

Comment

The synthesis of α-aminophosphonates has attracted much interest because of their biological activity and structural analogy to α-amino acids (Fields, 1999). They also act as peptide mimics (Kafarski et al., 1991), enzyme inhibitors (Allen et al., 1989), haptens of catalytic antibodies (Hirschmann et al., 1994), antibiotics and pharmacological agents (Baylis et al., 1984) and the analogues of amino acids, aminophosphonic and aminophophinic acids as plant growth regulators and herbicides (Miliszkiewicz et al., 1992). As a result, a variety of synthetic approaches have been developed for the synthesis of α-aminophosphonates. The title compound (I) exhibits antibacterial activity against Gram positive as well as Gram negative bacteria (Syam et al., 2007)

The molecular structure of the title compound is shown in Fig. 1. (I). The P—O bond distances are in good agreement with those in related structures (Boehlow et al., 1997; Yang et al., 2005). The P1—C15 bond length is in good agreement with the reported values of 1.821 (6) Å, 1.808 (9) Å, 1.813 (6)Å in related structures (Rużić-Toroš et al., 1978; Sawka-Dobrowolska & Rułko, 1987; Sanders et al., 1996). The C9–N4 bond length (1.384 (2) Å) is intermediate between C—N and C=N double bond distances, which shows influence of the delocalization of electrons from the benzene ring. The P atom adopts a distorted tetrahedral configuration, with the angles in the range of 101.1 (1)° - 115.8 (1)°. The deformation of the PO3C tetrahedra may be explained in terms of steric effects from the adjacent bulky ethoxy groups. There are some differences between similar bonds in the P-O-C-C groups and this may be attributed to the larger than normal anisotropic displacement parameters of the atoms in the groups. This was not considered severe enough to model as disorder (Ezra & Collin, 1973; Sawka-Dobrowolska & Kowalik, 1985; Sanders et al., 1996). In the crystal structure, intermolecular O-H···O and N-H···O hydrogen bonds link pairs of molecules into centrosymmetric dimers. These dimers, are in turn, linked by weak intermolecular C-H···O hydrogen bonds into one-dimensional chains along [010](see Fig. 2). Additional stabilization is provided by very weak C—H···Cl interactions. .

Experimental

To a stirred solution of 2-amino-4-chlorophenol (0.72 g, 0.005 mol), 4-chloro benzaldehyde (0.005 mol) in anhydrous toluene (15 ml) was added dropwise. Stirring was continued at room temperature for lh. Then diethylphosphite (0.7 g, 0.005 mol) in anhydrous toulene (15 ml) was added dropwise. Stirring was continued at room temperature for another 0.5 h, later the mixture was heated under reflux for 4–6 h. After completion of the reaction (monitored by TLC) the solvent was removed under reduced pressure. The resulting residue was purified by column chromatography on silica gel using petroleum ether-ethyl acetate (8:2) as eluent. Colorless, prism shaped single crystals suitable for diffraction studies were grown by slow evaporation of a methanol solution of the title compound.

Refinement

All hydrogen atoms were placed in calculated positions with C-H = 0.93-0.97Å; N-H = 0.86Å and O-H = 0.82Å. They were included in the refinement in a riding-model approximation with Uiso(H) = 1.2Ueq(C,N) or 1.5Ueq(Cmethyl,O)

Figures

Fig. 1.
The molecular structure of the itle compound with displacement ellipsoids drawn at the 40% probability level. H atoms have been omitted.
Fig. 2.
Part of the crystal structure showing one-dimensional chains along [010]. Hydrogen bonds are shown as dashed lines.

Crystal data

C17H20Cl2NO4PZ = 2
Mr = 404.21F(000) = 420
Triclinic, P1Dx = 1.391 Mg m3Dm = 1.390 Mg m3Dm measured by not measured
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 7.790 (3) ÅCell parameters from 4863 reflections
b = 9.297 (4) Åθ = 2.3–28.4°
c = 14.372 (6) ŵ = 0.44 mm1
α = 82.817 (6)°T = 294 K
β = 80.842 (6)°Prism, colorless
γ = 70.323 (6)°0.25 × 0.25 × 0.13 mm
V = 964.7 (7) Å3

Data collection

Siemens SMART CCD area-detector diffractometer4863 independent reflections
Radiation source: fine-focus sealed tube3635 reflections with I > 2σ(I)
graphiteRint = 0.017
ω scansθmax = 28.4°, θmin = 2.3°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)h = −10→10
Tmin = 0.896, Tmax = 0.944k = −12→12
10997 measured reflectionsl = −19→19

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.053Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.159H-atom parameters constrained
S = 1.05w = 1/[σ2(Fo2) + (0.0937P)2 + 0.273P] where P = (Fo2 + 2Fc2)/3
4863 reflections(Δ/σ)max < 0.001
226 parametersΔρmax = 0.56 e Å3
0 restraintsΔρmin = −0.34 e Å3

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
P10.39158 (8)0.81933 (6)0.17033 (4)0.05033 (18)
Cl30.76222 (12)0.10544 (8)0.42621 (5)0.0856 (3)
Cl2−0.32728 (10)0.63628 (13)0.43963 (6)0.0973 (3)
O80.6784 (2)0.33466 (17)0.03123 (10)0.0610 (4)
H80.74020.2713−0.00610.092*
C150.4115 (3)0.6327 (2)0.23264 (13)0.0462 (4)
H150.49460.61670.28030.055*
O50.2676 (2)0.86066 (17)0.09700 (11)0.0619 (4)
C160.2269 (3)0.6284 (2)0.28494 (13)0.0449 (4)
N40.4997 (3)0.51803 (19)0.16550 (12)0.0555 (5)
H40.48460.54130.10690.067*
C100.6279 (3)0.3174 (2)0.28709 (14)0.0506 (5)
H100.56520.38000.33560.061*
C140.7033 (3)0.2733 (2)0.12175 (14)0.0474 (4)
O70.5926 (3)0.8172 (2)0.13357 (14)0.0790 (5)
C90.6079 (2)0.3719 (2)0.19319 (14)0.0435 (4)
O60.3313 (3)0.92357 (18)0.25403 (11)0.0662 (5)
C110.7415 (3)0.1695 (2)0.30794 (15)0.0550 (5)
C130.8153 (3)0.1274 (3)0.14481 (17)0.0600 (6)
H130.87830.06370.09690.072*
C120.8360 (3)0.0736 (3)0.23795 (18)0.0634 (6)
H120.9121−0.02510.25290.076*
C210.1714 (3)0.6774 (3)0.37545 (15)0.0567 (5)
H210.24950.70880.40480.068*
C19−0.1119 (3)0.6310 (3)0.38023 (17)0.0622 (6)
C200.0014 (3)0.6800 (3)0.42263 (16)0.0646 (6)
H20−0.03570.71500.48280.078*
C170.1099 (3)0.5794 (3)0.24381 (17)0.0646 (6)
H170.14600.54480.18350.078*
C18−0.0595 (4)0.5810 (4)0.2904 (2)0.0754 (7)
H18−0.13760.54870.26160.091*
C220.3166 (5)1.0826 (3)0.2469 (2)0.0840 (9)
H22A0.22711.14030.20480.101*
H22B0.43431.09450.22090.101*
C240.6719 (5)0.8128 (4)0.0351 (2)0.0952 (10)
H24A0.58900.7947−0.00230.114*
H24B0.68720.91100.01240.114*
C230.2602 (5)1.1411 (4)0.3403 (2)0.0903 (10)
H23A0.24941.24770.33530.135*
H23B0.35041.08500.38130.135*
H23C0.14371.12920.36570.135*
C250.8425 (6)0.6970 (6)0.0239 (3)0.148 (2)
H25A0.89220.6963−0.04170.222*
H25B0.82710.59960.04550.222*
H25C0.92520.71580.06010.222*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
P10.0602 (3)0.0418 (3)0.0429 (3)−0.0107 (2)0.0019 (2)−0.0079 (2)
Cl30.1068 (6)0.0725 (4)0.0536 (4)0.0006 (4)−0.0165 (3)0.0075 (3)
Cl20.0603 (4)0.1562 (8)0.0703 (5)−0.0335 (4)0.0017 (3)−0.0068 (5)
O80.0729 (10)0.0504 (8)0.0449 (8)0.0014 (7)−0.0067 (7)−0.0104 (6)
C150.0516 (10)0.0384 (9)0.0407 (9)−0.0028 (8)−0.0057 (8)−0.0070 (7)
O50.0798 (11)0.0474 (8)0.0463 (8)−0.0043 (7)−0.0086 (7)−0.0038 (6)
C160.0524 (10)0.0355 (8)0.0401 (9)−0.0045 (7)−0.0078 (8)−0.0038 (7)
N40.0666 (11)0.0432 (9)0.0396 (8)0.0062 (8)−0.0066 (8)−0.0081 (7)
C100.0520 (11)0.0473 (10)0.0449 (10)−0.0069 (8)−0.0017 (8)−0.0071 (8)
C140.0460 (10)0.0457 (10)0.0455 (10)−0.0072 (8)−0.0037 (8)−0.0088 (8)
O70.0733 (11)0.0911 (13)0.0722 (12)−0.0324 (10)0.0114 (9)−0.0145 (10)
C90.0404 (9)0.0386 (9)0.0463 (10)−0.0062 (7)−0.0030 (7)−0.0062 (7)
O60.0935 (12)0.0494 (8)0.0552 (9)−0.0257 (8)0.0070 (8)−0.0162 (7)
C110.0576 (12)0.0496 (11)0.0498 (11)−0.0071 (9)−0.0092 (9)−0.0002 (9)
C130.0604 (12)0.0482 (11)0.0565 (12)0.0038 (9)−0.0036 (10)−0.0140 (9)
C120.0623 (13)0.0452 (11)0.0655 (14)0.0060 (9)−0.0101 (11)−0.0042 (10)
C210.0623 (13)0.0642 (13)0.0442 (11)−0.0187 (10)−0.0053 (9)−0.0129 (9)
C190.0513 (11)0.0742 (15)0.0531 (12)−0.0124 (10)−0.0051 (9)0.0004 (11)
C200.0677 (14)0.0764 (15)0.0436 (11)−0.0162 (12)0.0013 (10)−0.0124 (10)
C170.0645 (13)0.0807 (16)0.0500 (12)−0.0205 (12)−0.0052 (10)−0.0212 (11)
C180.0658 (15)0.103 (2)0.0634 (15)−0.0306 (14)−0.0073 (12)−0.0221 (14)
C220.120 (2)0.0619 (15)0.0744 (17)−0.0419 (16)0.0128 (16)−0.0183 (13)
C240.084 (2)0.097 (2)0.079 (2)−0.0163 (17)0.0210 (16)0.0078 (17)
C230.119 (3)0.0762 (18)0.083 (2)−0.0425 (18)0.0148 (18)−0.0354 (15)
C250.090 (3)0.164 (4)0.123 (4)0.017 (3)0.034 (2)0.008 (3)

Geometric parameters (Å, °)

P1—O51.4712 (17)C13—C121.384 (3)
P1—O61.5531 (16)C13—H130.9300
P1—O71.565 (2)C12—H120.9300
P1—C151.819 (2)C21—C201.382 (3)
Cl3—C111.743 (2)C21—H210.9300
Cl2—C191.745 (3)C19—C201.367 (4)
O8—C141.370 (2)C19—C181.380 (4)
O8—H80.8200C20—H200.9300
C15—N41.447 (2)C17—C181.377 (4)
C15—C161.523 (3)C17—H170.9300
C15—H150.9800C18—H180.9300
C16—C171.381 (3)C22—C231.457 (4)
C16—C211.387 (3)C22—H22A0.9700
N4—C91.384 (2)C22—H22B0.9700
N4—H40.8600C24—C251.402 (5)
C10—C111.388 (3)C24—H24A0.9700
C10—C91.394 (3)C24—H24B0.9700
C10—H100.9300C23—H23A0.9600
C14—C131.376 (3)C23—H23B0.9600
C14—C91.407 (3)C23—H23C0.9600
O7—C241.450 (4)C25—H25A0.9600
O6—C221.436 (3)C25—H25B0.9600
C11—C121.377 (3)C25—H25C0.9600
O5—P1—O6115.79 (10)C20—C21—C16120.8 (2)
O5—P1—O7114.61 (11)C20—C21—H21119.6
O6—P1—O7104.38 (10)C16—C21—H21119.6
O5—P1—C15113.51 (10)C20—C19—C18120.8 (2)
O6—P1—C15101.05 (9)C20—C19—Cl2119.40 (19)
O7—P1—C15106.08 (11)C18—C19—Cl2119.8 (2)
C14—O8—H8109.5C19—C20—C21119.6 (2)
N4—C15—C16115.71 (17)C19—C20—H20120.2
N4—C15—P1107.67 (14)C21—C20—H20120.2
C16—C15—P1111.24 (12)C18—C17—C16121.3 (2)
N4—C15—H15107.3C18—C17—H17119.4
C16—C15—H15107.3C16—C17—H17119.4
P1—C15—H15107.3C17—C18—C19119.2 (2)
C17—C16—C21118.4 (2)C17—C18—H18120.4
C17—C16—C15121.66 (18)C19—C18—H18120.4
C21—C16—C15119.92 (18)O6—C22—C23109.6 (2)
C9—N4—C15121.70 (16)O6—C22—H22A109.8
C9—N4—H4119.1C23—C22—H22A109.8
C15—N4—H4119.1O6—C22—H22B109.8
C11—C10—C9119.82 (18)C23—C22—H22B109.8
C11—C10—H10120.1H22A—C22—H22B108.2
C9—C10—H10120.1C25—C24—O7111.0 (3)
O8—C14—C13124.40 (18)C25—C24—H24A109.4
O8—C14—C9115.33 (17)O7—C24—H24A109.4
C13—C14—C9120.25 (19)C25—C24—H24B109.4
C24—O7—P1124.7 (2)O7—C24—H24B109.4
N4—C9—C10123.96 (17)H24A—C24—H24B108.0
N4—C9—C14117.57 (17)C22—C23—H23A109.5
C10—C9—C14118.47 (17)C22—C23—H23B109.5
C22—O6—P1125.27 (17)H23A—C23—H23B109.5
C12—C11—C10121.7 (2)C22—C23—H23C109.5
C12—C11—Cl3119.93 (17)H23A—C23—H23C109.5
C10—C11—Cl3118.42 (17)H23B—C23—H23C109.5
C14—C13—C12121.27 (19)C24—C25—H25A109.5
C14—C13—H13119.4C24—C25—H25B109.5
C12—C13—H13119.4H25A—C25—H25B109.5
C11—C12—C13118.53 (19)C24—C25—H25C109.5
C11—C12—H12120.7H25A—C25—H25C109.5
C13—C12—H12120.7H25B—C25—H25C109.5
O5—P1—C15—N465.76 (17)O5—P1—O6—C22−65.0 (3)
O6—P1—C15—N4−169.61 (14)O7—P1—O6—C2262.0 (3)
O7—P1—C15—N4−60.97 (16)C15—P1—O6—C22172.0 (2)
O5—P1—C15—C16−62.00 (16)C9—C10—C11—C12−0.2 (4)
O6—P1—C15—C1662.62 (15)C9—C10—C11—Cl3−179.79 (16)
O7—P1—C15—C16171.27 (13)O8—C14—C13—C12179.0 (2)
N4—C15—C16—C17−30.9 (3)C9—C14—C13—C120.5 (4)
P1—C15—C16—C1792.4 (2)C10—C11—C12—C13−0.2 (4)
N4—C15—C16—C21150.44 (18)Cl3—C11—C12—C13179.4 (2)
P1—C15—C16—C21−86.3 (2)C14—C13—C12—C110.1 (4)
C16—C15—N4—C9−84.7 (2)C17—C16—C21—C20−1.3 (3)
P1—C15—N4—C9150.18 (17)C15—C16—C21—C20177.43 (19)
O5—P1—O7—C24−16.7 (3)C18—C19—C20—C21−1.0 (4)
O6—P1—O7—C24−144.4 (2)Cl2—C19—C20—C21−179.39 (19)
C15—P1—O7—C24109.4 (2)C16—C21—C20—C191.3 (4)
C15—N4—C9—C106.3 (3)C21—C16—C17—C181.0 (4)
C15—N4—C9—C14−173.55 (18)C15—C16—C17—C18−177.7 (2)
C11—C10—C9—N4−179.1 (2)C16—C17—C18—C19−0.7 (4)
C11—C10—C9—C140.7 (3)C20—C19—C18—C170.7 (4)
O8—C14—C9—N40.3 (3)Cl2—C19—C18—C17179.1 (2)
C13—C14—C9—N4179.0 (2)P1—O6—C22—C23−178.8 (2)
O8—C14—C9—C10−179.55 (19)P1—O7—C24—C25−130.1 (4)
C13—C14—C9—C10−0.9 (3)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
N4—H4···O8i0.862.483.286 (3)157
C24—H24B···O5ii0.972.573.504 (4)162
O8—H8···O5i0.821.922.636 (2)145
C15—H15···Cl2iii0.982.913.872 (3)165
N4—H4···O80.862.282.634 (3)105
C24—H24A···O50.972.593.029 (5)107

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

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: LH2891).

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