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ISSN: 2056-9890

Phenyl bis­­(m-tolyl­amido)­phosphinate

aDepartment of Chemistry, Ferdowsi University of Mashhad, Mashhad 91779, Iran, and bDepartment of Chemistry, Faculty of Science, Masaryk University, Kotlarska 2, Brno CZ-61137, Czech Republic
*Correspondence e-mail: mehrdad_pourayoubi@yahoo.com

(Received 14 June 2011; accepted 24 June 2011; online 2 July 2011)

The P atom of the title compound, C20H21N2O2P, has a distorted tetra­hedral configuration; the bond angles at P are in the range 96.11 (6)–117.32 (8)°. The N atom exhibits sp2 character. In the crystal, mol­ecules are connected via N—H⋯O hydrogen bonds into bands along the a axis, consisting of R22(8) rings.

Related literature

For background to compounds having a P(=O)(O)(N)(N) skeleton, see: Sabbaghi et al. (2010[Sabbaghi, F., Mancilla Percino, T., Pourayoubi, M. & Leyva, M. A. (2010). Acta Cryst. E66, o1755.]). For bond lengths in related structures, see: Ghadimi et al. (2009[Ghadimi, S., Pourayoubi, M. & Ebrahimi Valmoozi, A. A. (2009). Z. Naturforsch. Teil B, 64, 565-569.]); Rudd et al. (1996[Rudd, M. D., Lindeman, S. V. & Husebye, S. (1996). Acta Chem. Scand. 50, 759-774.]). For graph-set notation, see Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]).

[Scheme 1]

Experimental

Crystal data
  • C20H21N2O2P

  • Mr = 352.36

  • Orthorhombic, P n a 21

  • a = 10.1930 (2) Å

  • b = 16.8789 (3) Å

  • c = 10.4588 (3) Å

  • V = 1799.40 (7) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.17 mm−1

  • T = 120 K

  • 0.30 × 0.30 × 0.20 mm

Data collection
  • Oxford Diffraction Xcalibur Sapphire2 diffractometer

  • Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2009[Oxford Diffraction (2009). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Yarnton, England.]) Tmin = 0.959, Tmax = 1.000

  • 20798 measured reflections

  • 2819 independent reflections

  • 2647 reflections with I > 2σ(I)

  • Rint = 0.018

Refinement
  • R[F2 > 2σ(F2)] = 0.022

  • wR(F2) = 0.062

  • S = 1.05

  • 2819 reflections

  • 228 parameters

  • 1 restraint

  • H-atom parameters constrained

  • Δρmax = 0.17 e Å−3

  • Δρmin = −0.23 e Å−3

  • Absolute structure: Flack (1983[Flack, H. D. (1983). Acta Cryst. A39, 876-881.]), 1140 Friedel pairs

  • Flack parameter: −0.04 (7)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1B⋯O1i 0.88 2.14 2.9917 (16) 162
N2—H2A⋯O2ii 0.88 2.53 3.3929 (16) 166
Symmetry codes: (i) [x+{\script{1\over 2}}, -y+{\script{1\over 2}}, z]; (ii) [x-{\script{1\over 2}}, -y+{\script{1\over 2}}, z].

Data collection: CrysAlis CCD (Oxford Diffraction, 2009[Oxford Diffraction (2009). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Yarnton, England.]); cell refinement: CrysAlis RED (Oxford Diffraction, 2009[Oxford Diffraction (2009). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Yarnton, England.]); data reduction: CrysAlis RED; 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: Mercury (Macrae et al., 2008[Macrae, C. F., Bruno, I. J., Chisholm, J. A., Edgington, P. R., McCabe, P., Pidcock, E., Rodriguez-Monge, L., Taylor, R., van de Streek, J. & Wood, P. A. (2008). J. Appl. Cryst. 41, 466-470.]); software used to prepare material for publication: enCIFer (Allen et al., 2004[Allen, F. H., Johnson, O., Shields, G. P., Smith, B. R. & Towler, M. (2004). J. Appl. Cryst. 37, 335-338.]).

Supporting information


Comment top

Structure determination of the title compound, P(O)[OC6H5][NHC6H4(m-CH3)]2 (Fig. 1), was performed as a part of a project in our laboratory on the synthesis of compounds having a P(O)(O)(N)(N) skeleton (Sabbaghi et al., 2010). Single crystals of title compound were obtained from a mixture of CHCl3/CH3OH (4:1 v/v) after slow evaporation at room temperature.

The PO (1.4692 (11) Å), P—O (1.5941 (12) Å) and P—N (1.6374 (15) Å & 1.6469 (13) Å) bond lengths are usual for this category of compounds (Ghadimi et al., 2009). The P atom has a distorted tetrahedral configuration (Fig. 1), as it has been noted for the other phosphoramidates and their chalco-derivatives (Rudd et al., 1996). The bond angles at the P atom vary in the range from 96.11 (6)°-117.32 (8)°. The C1—O2—P1, C7—N1—P1 and C14—N2—P1 angles are 120.49 (9)°, 127.29 (11)° and 130.85 (11)°, respectively.

Prior to the constrained refinement of the imino H atoms, we have tested a free refinement of these atoms localized from a difference Fourier map. The results suggested an almost perfect in-plane arrangement of both H atoms with the corresponding P,N,C atoms. Therefore, the imino groups were assigned a planar geometry to reduce the number of parameters and to maintain more appropriate N—H bond lengths.

One of the two N—H units adopts a syn orientation with respect to the phosphoryl group, while the other exists in an anti orientation.

In the crystal, each molecule is hydrogen-bonded to two adjacent molecules through N—H···O hydrogen bonds, building R22(8) rings (Bernstein et al., 1995), and forming linear arrangements parallel to [100] (Fig. 2, Table 1).

Related literature top

For background to compounds having a P(O)(O)(N)(N) skeleton, see: Sabbaghi et al. (2010). For bond lengths in related structures, see: Ghadimi et al. (2009); Rudd et al. (1996). For graph-set notation, see Bernstein et al. (1995).

Experimental top

To a solution of phenyl dichlorophosphate (2.35 mmol) in chloroform (15 ml), a solution of meta-toluidine (9.40 mmol) in chloroform (30 ml) was added at 273 K. After 4 h of stirring, the solvent was evaporated in vacuum. The solid was washed with distilled water. Single crystals, suitable for crystallography, were obtained from a solution of the title compound in chloroform and methanol (4:1) after slow evaporation at room temperature. IR (KBr, cm-1): 3402, 3124, 2890, 2607, 1586, 1494, 1401, 1293, 1182, 1023, 946, 757.

Refinement top

Hydrogen atoms in phenyl and NH groups were positioned geometrically and refined as riding with their Uiso set to 1.2Ueq of the parent atoms. Hydrogen atoms in methyl groups were positioned geometrically and refined as rotating with their Uiso set to 1.5Ueq of the parent atoms.

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2009); cell refinement: CrysAlis RED (Oxford Diffraction, 2009); data reduction: CrysAlis RED (Oxford Diffraction, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: Mercury (Macrae et al., 2008); software used to prepare material for publication: enCIFer (Allen et al., 2004).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound with ellipsoids shown at the 50% probability level.
[Figure 2] Fig. 2. Part of the crystal structure with hydrogen bonds shown as dotted lines (the C—H hydrogen atoms are omitted for clarity).
Phenyl bis(m-tolylamido)phosphinate top
Crystal data top
C20H21N2O2PDx = 1.301 Mg m3
Mr = 352.36Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, Pna21Cell parameters from 13732 reflections
a = 10.1930 (2) Åθ = 3.0–27.2°
b = 16.8789 (3) ŵ = 0.17 mm1
c = 10.4588 (3) ÅT = 120 K
V = 1799.40 (7) Å3BLOCK, colourless
Z = 40.30 × 0.30 × 0.20 mm
F(000) = 744
Data collection top
Oxford Diffraction Xcalibur Sapphire2
diffractometer
2819 independent reflections
Radiation source: Enhance (Mo) X-ray Source2647 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.018
Detector resolution: 8.4353 pixels mm-1θmax = 25.0°, θmin = 3.0°
ω scansh = 1212
Absorption correction: multi-scan
(CrysAlis RED; Oxford Diffraction, 2009)
k = 2020
Tmin = 0.959, Tmax = 1.000l = 812
20798 measured reflections
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.022H-atom parameters constrained
wR(F2) = 0.062 w = 1/[σ2(Fo2) + (0.046P)2]
where P = (Fo2 + 2Fc2)/3
S = 1.05(Δ/σ)max = 0.001
2819 reflectionsΔρmax = 0.17 e Å3
228 parametersΔρmin = 0.23 e Å3
1 restraintAbsolute structure: Flack (1983), 1140 Friedel pairs
Primary atom site location: structure-invariant direct methodsAbsolute structure parameter: 0.04 (7)
Crystal data top
C20H21N2O2PV = 1799.40 (7) Å3
Mr = 352.36Z = 4
Orthorhombic, Pna21Mo Kα radiation
a = 10.1930 (2) ŵ = 0.17 mm1
b = 16.8789 (3) ÅT = 120 K
c = 10.4588 (3) Å0.30 × 0.30 × 0.20 mm
Data collection top
Oxford Diffraction Xcalibur Sapphire2
diffractometer
2819 independent reflections
Absorption correction: multi-scan
(CrysAlis RED; Oxford Diffraction, 2009)
2647 reflections with I > 2σ(I)
Tmin = 0.959, Tmax = 1.000Rint = 0.018
20798 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.022H-atom parameters constrained
wR(F2) = 0.062Δρmax = 0.17 e Å3
S = 1.05Δρmin = 0.23 e Å3
2819 reflectionsAbsolute structure: Flack (1983), 1140 Friedel pairs
228 parametersAbsolute structure parameter: 0.04 (7)
1 restraint
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 > 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) top
xyzUiso*/Ueq
P10.72349 (4)0.24971 (2)0.91839 (5)0.01542 (11)
O10.61830 (10)0.19795 (6)0.96582 (11)0.0194 (3)
O20.82530 (10)0.20973 (6)0.82235 (12)0.0184 (3)
N10.83286 (12)0.28002 (7)1.02210 (16)0.0179 (3)
H1B0.91560.27530.99930.022*
N20.65260 (12)0.32433 (7)0.84411 (15)0.0193 (3)
H2A0.56630.32360.84620.023*
C10.78034 (13)0.16622 (9)0.71528 (18)0.0171 (4)
C20.76338 (16)0.20366 (10)0.60039 (19)0.0240 (4)
H2B0.77400.25940.59370.029*
C30.73032 (17)0.15880 (11)0.49380 (19)0.0269 (4)
H3A0.71640.18390.41360.032*
C40.71767 (15)0.07733 (11)0.5049 (2)0.0268 (4)
H4A0.69780.04640.43150.032*
C50.73373 (15)0.04090 (10)0.6218 (2)0.0250 (4)
H5A0.72400.01490.62870.030*
C60.76376 (14)0.08496 (10)0.72845 (18)0.0210 (4)
H6A0.77300.06030.80960.025*
C70.80937 (15)0.31292 (8)1.14394 (17)0.0167 (4)
C80.68462 (15)0.31324 (9)1.19924 (19)0.0217 (4)
H8A0.61240.29151.15380.026*
C90.66553 (16)0.34526 (9)1.32059 (18)0.0230 (4)
C100.77167 (16)0.37699 (9)1.38620 (19)0.0243 (4)
H10A0.75950.39891.46900.029*
C110.89519 (16)0.37666 (9)1.33103 (18)0.0240 (4)
H11A0.96740.39851.37640.029*
C120.91464 (15)0.34502 (9)1.21091 (18)0.0208 (4)
H12A0.99980.34511.17400.025*
C130.53035 (17)0.34519 (12)1.3794 (2)0.0357 (5)
H13A0.53690.33151.47030.054*
H13B0.47520.30611.33560.054*
H13C0.49110.39791.37060.054*
C140.70709 (15)0.38945 (9)0.77755 (18)0.0177 (4)
C150.62148 (15)0.44120 (9)0.71729 (17)0.0198 (4)
H15A0.52980.43190.72330.024*
C160.66624 (16)0.50657 (9)0.64807 (17)0.0212 (4)
C170.80128 (15)0.51933 (9)0.64137 (18)0.0219 (4)
H17A0.83460.56350.59530.026*
C180.88614 (15)0.46829 (9)0.70120 (18)0.0232 (4)
H18A0.97780.47810.69590.028*
C190.84227 (15)0.40269 (9)0.76930 (18)0.0201 (4)
H19A0.90270.36770.80930.024*
C200.57089 (18)0.55834 (10)0.57636 (19)0.0327 (5)
H20A0.60480.61260.57280.049*
H20B0.48600.55810.62040.049*
H20C0.55980.53800.48930.049*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
P10.01458 (18)0.01538 (17)0.0163 (2)0.00013 (14)0.0010 (2)0.00022 (17)
O10.0181 (5)0.0198 (5)0.0203 (7)0.0003 (4)0.0018 (5)0.0011 (5)
O20.0169 (5)0.0202 (5)0.0180 (7)0.0005 (4)0.0004 (5)0.0025 (5)
N10.0127 (6)0.0217 (6)0.0195 (8)0.0011 (5)0.0024 (6)0.0030 (6)
N20.0130 (6)0.0196 (6)0.0253 (9)0.0001 (5)0.0007 (6)0.0031 (6)
C10.0131 (7)0.0208 (7)0.0175 (10)0.0007 (6)0.0014 (7)0.0034 (7)
C20.0274 (9)0.0203 (8)0.0242 (12)0.0009 (6)0.0020 (8)0.0008 (8)
C30.0280 (9)0.0370 (10)0.0158 (11)0.0028 (8)0.0005 (8)0.0005 (9)
C40.0189 (8)0.0329 (9)0.0287 (12)0.0002 (7)0.0021 (8)0.0120 (9)
C50.0182 (8)0.0197 (8)0.0372 (13)0.0017 (6)0.0017 (8)0.0078 (9)
C60.0182 (8)0.0218 (8)0.0231 (11)0.0003 (6)0.0002 (7)0.0024 (8)
C70.0198 (7)0.0129 (7)0.0174 (10)0.0019 (6)0.0017 (7)0.0026 (7)
C80.0191 (8)0.0210 (7)0.0250 (11)0.0026 (6)0.0013 (7)0.0013 (8)
C90.0257 (9)0.0214 (8)0.0220 (10)0.0005 (6)0.0066 (8)0.0007 (8)
C100.0333 (9)0.0197 (7)0.0197 (12)0.0007 (7)0.0019 (8)0.0024 (7)
C110.0246 (8)0.0235 (8)0.0240 (11)0.0019 (6)0.0042 (8)0.0030 (8)
C120.0190 (8)0.0212 (7)0.0222 (10)0.0005 (6)0.0009 (7)0.0018 (7)
C130.0302 (10)0.0449 (10)0.0322 (13)0.0055 (8)0.0109 (9)0.0121 (9)
C140.0204 (8)0.0161 (7)0.0167 (10)0.0013 (6)0.0022 (7)0.0024 (7)
C150.0159 (7)0.0207 (7)0.0229 (10)0.0001 (6)0.0026 (7)0.0005 (8)
C160.0254 (9)0.0190 (7)0.0190 (10)0.0015 (6)0.0038 (7)0.0015 (8)
C170.0269 (9)0.0189 (8)0.0198 (11)0.0057 (7)0.0048 (8)0.0004 (8)
C180.0182 (8)0.0232 (8)0.0281 (12)0.0050 (6)0.0036 (8)0.0038 (8)
C190.0164 (8)0.0201 (7)0.0240 (10)0.0015 (6)0.0009 (7)0.0014 (7)
C200.0334 (10)0.0279 (9)0.0368 (13)0.0033 (7)0.0044 (9)0.0118 (9)
Geometric parameters (Å, º) top
P1—O11.4692 (11)C9—C101.389 (2)
P1—O21.5941 (12)C9—C131.509 (2)
P1—N11.6374 (15)C10—C111.385 (2)
P1—N21.6469 (13)C10—H10A0.9500
O2—C11.416 (2)C11—C121.379 (3)
N1—C71.410 (2)C11—H11A0.9500
N1—H1B0.8800C12—H12A0.9500
N2—C141.415 (2)C13—H13A0.9800
N2—H2A0.8800C13—H13B0.9800
C1—C21.369 (3)C13—H13C0.9800
C1—C61.389 (2)C14—C151.386 (2)
C2—C31.389 (3)C14—C191.399 (2)
C2—H2B0.9500C15—C161.396 (2)
C3—C41.386 (3)C15—H15A0.9500
C3—H3A0.9500C16—C171.395 (2)
C4—C51.378 (3)C16—C201.507 (2)
C4—H4A0.9500C17—C181.372 (2)
C5—C61.375 (3)C17—H17A0.9500
C5—H5A0.9500C18—C191.390 (2)
C6—H6A0.9500C18—H18A0.9500
C7—C121.391 (2)C19—H19A0.9500
C7—C81.397 (2)C20—H20A0.9800
C8—C91.393 (3)C20—H20B0.9800
C8—H8A0.9500C20—H20C0.9800
O1—P1—O2115.86 (6)C11—C10—C9120.06 (17)
O1—P1—N1117.32 (8)C11—C10—H10A120.0
O2—P1—N196.11 (6)C9—C10—H10A120.0
O1—P1—N2107.09 (6)C12—C11—C10120.77 (16)
O2—P1—N2108.19 (7)C12—C11—H11A119.6
N1—P1—N2111.85 (7)C10—C11—H11A119.6
C1—O2—P1120.49 (9)C11—C12—C7119.90 (15)
C7—N1—P1127.29 (11)C11—C12—H12A120.0
C7—N1—H1B116.4C7—C12—H12A120.0
P1—N1—H1B116.4C9—C13—H13A109.5
C14—N2—P1130.85 (11)C9—C13—H13B109.5
C14—N2—H2A114.6H13A—C13—H13B109.5
P1—N2—H2A114.6C9—C13—H13C109.5
C2—C1—C6121.86 (17)H13A—C13—H13C109.5
C2—C1—O2119.73 (13)H13B—C13—H13C109.5
C6—C1—O2118.25 (16)C15—C14—C19119.44 (15)
C1—C2—C3118.92 (15)C15—C14—N2117.78 (13)
C1—C2—H2B120.5C19—C14—N2122.77 (15)
C3—C2—H2B120.5C14—C15—C16121.87 (14)
C4—C3—C2119.75 (18)C14—C15—H15A119.1
C4—C3—H3A120.1C16—C15—H15A119.1
C2—C3—H3A120.1C17—C16—C15118.07 (15)
C5—C4—C3120.38 (18)C17—C16—C20121.46 (15)
C5—C4—H4A119.8C15—C16—C20120.37 (14)
C3—C4—H4A119.8C18—C17—C16120.14 (15)
C6—C5—C4120.32 (15)C18—C17—H17A119.9
C6—C5—H5A119.8C16—C17—H17A119.9
C4—C5—H5A119.8C17—C18—C19122.08 (14)
C5—C6—C1118.72 (17)C17—C18—H18A119.0
C5—C6—H6A120.6C19—C18—H18A119.0
C1—C6—H6A120.6C18—C19—C14118.40 (15)
C12—C7—C8119.48 (16)C18—C19—H19A120.8
C12—C7—N1118.51 (14)C14—C19—H19A120.8
C8—C7—N1122.01 (15)C16—C20—H20A109.5
C9—C8—C7120.39 (16)C16—C20—H20B109.5
C9—C8—H8A119.8H20A—C20—H20B109.5
C7—C8—H8A119.8C16—C20—H20C109.5
C10—C9—C8119.41 (15)H20A—C20—H20C109.5
C10—C9—C13120.67 (17)H20B—C20—H20C109.5
C8—C9—C13119.92 (16)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1B···O1i0.882.142.9917 (16)162
N2—H2A···O2ii0.882.533.3929 (16)166
Symmetry codes: (i) x+1/2, y+1/2, z; (ii) x1/2, y+1/2, z.

Experimental details

Crystal data
Chemical formulaC20H21N2O2P
Mr352.36
Crystal system, space groupOrthorhombic, Pna21
Temperature (K)120
a, b, c (Å)10.1930 (2), 16.8789 (3), 10.4588 (3)
V3)1799.40 (7)
Z4
Radiation typeMo Kα
µ (mm1)0.17
Crystal size (mm)0.30 × 0.30 × 0.20
Data collection
DiffractometerOxford Diffraction Xcalibur Sapphire2
diffractometer
Absorption correctionMulti-scan
(CrysAlis RED; Oxford Diffraction, 2009)
Tmin, Tmax0.959, 1.000
No. of measured, independent and
observed [I > 2σ(I)] reflections
20798, 2819, 2647
Rint0.018
(sin θ/λ)max1)0.595
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.022, 0.062, 1.05
No. of reflections2819
No. of parameters228
No. of restraints1
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.17, 0.23
Absolute structureFlack (1983), 1140 Friedel pairs
Absolute structure parameter0.04 (7)

Computer programs: CrysAlis CCD (Oxford Diffraction, 2009), CrysAlis RED (Oxford Diffraction, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), Mercury (Macrae et al., 2008), enCIFer (Allen et al., 2004).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1B···O1i0.882.142.9917 (16)162
N2—H2A···O2ii0.882.533.3929 (16)166
Symmetry codes: (i) x+1/2, y+1/2, z; (ii) x1/2, y+1/2, z.
 

Acknowledgements

Support of this investigation by Ferdowsi University of Mashhad is gratefully acknowledged.

References

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