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Acta Crystallogr Sect E Struct Rep Online. 2009 November 1; 65(Pt 11): o2696–o2697.
Published online 2009 October 10. doi:  10.1107/S1600536809040367
PMCID: PMC2971085

3-(6-Methyl-2-pyrid­yl)-2-phenyl-3,4-dihydro-1,3,2-benzoxaza­phosphinine 2-oxide

Abstract

In the title compound, C19H17N2O2P, the six-membered 1,3,2-oxaza­phosphinine ring adopts a boat conformation with the phosphoryl O atom in an equatorial position. The dihedral angle between the 6-methyl-2-pyridyl and phenyl groups is 75.5 (1)°. These substituents are trans to each other, and are oriented at angles of 57.2 (1) and 74.8 (1)°, respectively, to the benzene ring. The crystal structure is stabilized by intra- and inter­molecular hydrogen bonds. The phosphoryl O atom participates in inter­molecular C—H(...)O inter­actions with the neighbouring mol­ecules, forming centrosymmetric R 2 2(14) dimers.

Related literature

For the biological activity of organophospho­rus compounds, see: Hoagland (1988 [triangle]); Smith (1983 [triangle]); Molodykh et al. (1990 [triangle]). For P—O and P=O bond lengths in related structures, see: Brzozowski et al. (1990 [triangle]); Angelov et al. (2002 [triangle]); Kant et al. (2009 [triangle]). For P—N bond lengths in related structures, see: Radha Krishna et al. (2007 [triangle]); Yang et al. (1988 [triangle]); Subramanian et al. (1989 [triangle]); Selladurai & Subramanian (1990 [triangle]); Selladurai et al. (1991 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-65-o2696-scheme1.jpg

Experimental

Crystal data

  • C19H17N2O2P
  • M r = 336.32
  • Triclinic, An external file that holds a picture, illustration, etc.
Object name is e-65-o2696-efi1.jpg
  • a = 7.2238 (8) Å
  • b = 8.6573 (8) Å
  • c = 13.7265 (14) Å
  • α = 95.216 (8)°
  • β = 94.397 (9)°
  • γ = 94.330 (9)°
  • V = 849.42 (15) Å3
  • Z = 2
  • Mo Kα radiation
  • μ = 0.18 mm−1
  • T = 293 K
  • 0.28 × 0.18 × 0.08 mm

Data collection

  • Oxford Diffraction Xcalibur diffractometer
  • Absorption correction: none
  • 12457 measured reflections
  • 5006 independent reflections
  • 3069 reflections with I > 2σ(I)
  • R int = 0.030

Refinement

  • R[F 2 > 2σ(F 2)] = 0.052
  • wR(F 2) = 0.173
  • S = 1.14
  • 5006 reflections
  • 217 parameters
  • H-atom parameters constrained
  • Δρmax = 0.36 e Å−3
  • Δρmin = −0.33 e Å−3

Data collection: CrysAlis Pro (Oxford Diffraction, 2007 [triangle]); cell refinement: CrysAlis Pro (Oxford Diffraction, 2007 [triangle]); data reduction: CrysAlis RED (Oxford Diffraction, 2007 [triangle]); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: ZORTEP (Zsolnai, 1997 [triangle]); software used to prepare material for publication: enCIFer (Allen et al., 2004 [triangle]) and PARST95 (Nardelli, 1995 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809040367/bh2245sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809040367/bh2245Isup2.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

As organophosphorus compounds are ubiquitous, they have found multifaceted applications in nature. They can be used as insecticides and herbicides (Hoagland et al., 1988), fungicides (Smith et al., 1983), plant growth regulators and present also antifungal activity (Molodykh et al., 1990). The significant activity of all these compounds was accredited to the presence of six membered heterocyclic rings. In view of these activities, the title compound, (I), has been studied, as a part of our ongoing investigation to find out the influence of different substituents on the conformation of the heterocyclic ring.

In the molecular structure (Fig. 1), the oxazaphosphinine ring exhibits a boat conformation where atoms C6/C7/C12/O4 are almost coplanar and atoms P1 and N2 displaced in the same direction by 0.936 (1) and 0.936 (1) Å, respectively. The single and double bond lengths of P and O atoms are in good agreement with the similar structures reported previously (Brzozowski et al., 1990; Angelov et al., 2002; Kant et al., 2009). The P—N bond length, 1.6702 (14) Å, and the P—N—C bond angle, 120.30 (13)°, are comparable with the related structure of [1,3,2]-oxazaphosphorine-6-sulfide (Radha Krishna et al., 2007), but the bond distance shows relatively higher value when compared with the similar benzoxazaphosphorine structures (Yang et al., 1988; Subramanian et al., 1989; Selladurai & Subramanian, 1990; Selladurai et al., 1991). The N3—C13 and N3—C14 bond lengths fall between the expected single bond and double bond distances, showing the partial double bond character at N3.

In the crystal structure, the phosphoryl O atom participates in intermolecular C—H···O interactions with the neighboring molecules, to form centrosymmetric R22(14) dimers, along [011] (Fig. 2).

Experimental

A solution of phenylphosphonic dichloride (0.002 mol) in 25 ml of dry THF was added dropwise over a period of 20 min. to a stirred solution of 2-{[(6-methyl-2-pyridyl)amino]methyl}phenol (0.002 mol) and triethylamine (0.004 mol) in 30 ml of dry THF. After completion of the addition, the temperature of the reaction mixture was slowly raised to room temperature and stirred for 30 min. The reaction mixture was then heated to 318–323 K and maintained at that temperature for 3 h. under stirring. Completion of the reaction was monitored by TLC analysis. Triethylamine hydrochloride was filtered from the reaction mixture and the solvent was removed under reduced pressure. The crude product was purified by column chromatography on silica gel (100–200 mesh, ethyl acetate:hexane) to afford pure product. Transparent, colorless plate-shaped single crystals are obtained by slow evaporation of a 2-proponal solution.

Refinement

All C-bonded H-atoms were positioned geometrically and refined using a riding model with d(C—H) = 0.93 Å, Uiso(H) = 1.2Ueq(C) for aromatic, 0.97 Å, Uiso(H) = 1.2Ueq(C) for CH2 group and 0.96 Å, Uiso(H) = 1.5Ueq(C) for CH3 group.

Figures

Fig. 1.
View of the molecule showing the atom-labeling scheme. Displacement ellipsoids are drawn at the 40% probability level.
Fig. 2.
Packing of the molecules in the unit cell.

Crystal data

C19H17N2O2PZ = 2
Mr = 336.32F(000) = 352
Triclinic, P1Dx = 1.315 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 7.2238 (8) ÅCell parameters from 5006 reflections
b = 8.6573 (8) Åθ = 3.3–30.1°
c = 13.7265 (14) ŵ = 0.18 mm1
α = 95.216 (8)°T = 293 K
β = 94.397 (9)°Plate, colourless
γ = 94.330 (9)°0.28 × 0.18 × 0.08 mm
V = 849.42 (15) Å3

Data collection

Oxford Diffraction Xcalibur diffractometer3069 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.030
graphiteθmax = 30.1°, θmin = 3.3°
ω–2θ scansh = −10→10
12457 measured reflectionsk = −12→12
5006 independent 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)] = 0.052Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.173H-atom parameters constrained
S = 1.14w = 1/[σ2(Fo2) + (0.0909P)2] where P = (Fo2 + 2Fc2)/3
5006 reflections(Δ/σ)max < 0.001
217 parametersΔρmax = 0.36 e Å3
0 restraintsΔρmin = −0.33 e Å3
0 constraints

Special details

Refinement. Weighted least-squares planes through the starred atoms (Nardelli, Musatti, Domiano & Andreetti Ric.Sci.(1965),15(II—A),807). Equation of the plane: m1*X+m2*Y+m3*Z=dPlane 1 m1 = 0.38775(0.00078) m2 = 0.69013(0.00101) m3 = -0.61104(0.00092) D = -0.04785(0.00813) Atom d s d/s (d/s)**2 C6 * 0.0033 0.0020 1.652 2.729 C7 * -0.0061 0.0019 - 3.190 10.179 C12 * 0.0060 0.0019 3.207 10.286 O4 * -0.0017 0.0014 - 1.201 1.443 P1 0.9362 0.0005 1909.984 3648038.000 N2 0.9357 0.0015 617.499 381304.969 ============ Sum((d/s)**2) for starred atoms 24.637 Chi-squared at 95% for 1 degrees of freedom: 3.84 The group of atoms deviates significantly from planarityPlane 2 m1 = 0.36501(0.00090) m2 = 0.72088(0.00066) m3 = -0.58915(0.00074) D = 0.19711(0.00721) Atom d s d/s (d/s)**2 C7 * -0.0010 0.0019 - 0.547 0.300 C8 * -0.0022 0.0022 - 1.022 1.044 C9 * 0.0076 0.0024 3.196 10.214 C10 * -0.0077 0.0023 - 3.346 11.194 C11 * 0.0029 0.0021 1.390 1.931 C12 * 0.0007 0.0019 0.353 0.125 ============ Sum((d/s)**2) for starred atoms 24.808 Chi-squared at 95% for 3 degrees of freedom: 7.81 The group of atoms deviates significantly from planarityPlane 3 m1 = -0.45957(0.00079) m2 = 0.86478(0.00046) m3 = -0.20235(0.00092) D = 2.02662(0.00192) Atom d s d/s (d/s)**2 C13 * 0.0050 0.0018 2.731 7.457 N3 * -0.0045 0.0018 - 2.513 6.313 C14 * 0.0033 0.0025 1.334 1.780 C16 * 0.0013 0.0026 0.508 0.258 C17 * -0.0009 0.0027 - 0.328 0.108 C18 * -0.0040 0.0024 - 1.686 2.842 ============ Sum((d/s)**2) for starred atoms 18.758 Chi-squared at 95% for 3 degrees of freedom: 7.81 The group of atoms deviates significantly from planarityPlane 4 m1 = -0.44454(0.00100) m2 = -0.15288(0.00101) m3 = -0.88262(0.00050) D = -4.64491(0.00165) Atom d s d/s (d/s)**2 C19 * 0.0128 0.0022 5.712 32.623 C20 * -0.0095 0.0029 - 3.274 10.717 C21 * -0.0074 0.0031 - 2.395 5.738 C22 * 0.0121 0.0031 3.908 15.276 C23 * 0.0012 0.0025 0.480 0.231 C24 * -0.0084 0.0020 - 4.200 17.636 ============ Sum((d/s)**2) for starred atoms 82.221 Chi-squared at 95% for 3 degrees of freedom: 7.81 The group of atoms deviates significantly from planarityDihedral angles formed by LSQ-planes Plane - plane angle (s.u.) angle (s.u.) 1 2 2.52 (0.07) 177.48 (0.07) 1 3 57.16 (0.06) 122.84 (0.06) 1 4 74.84 (0.08) 105.16 (0.08) 2 3 54.91 (0.06) 125.09 (0.06) 2 4 75.67 (0.07) 104.33 (0.07) 3 4 75.48 (0.08) 104.52 (0.08)

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2)

xyzUiso*/Ueq
P10.37783 (6)0.42101 (5)0.26648 (4)0.03578 (17)
O40.34114 (19)0.46439 (16)0.37866 (10)0.0459 (4)
N20.16623 (19)0.42897 (18)0.20981 (11)0.0360 (4)
O50.52630 (17)0.51923 (15)0.23013 (11)0.0491 (4)
C240.4304 (3)0.2230 (2)0.26798 (15)0.0399 (4)
C70.0443 (2)0.5645 (2)0.35210 (14)0.0380 (4)
C60.0029 (2)0.4431 (2)0.26737 (15)0.0413 (4)
H6A−0.03160.34380.29130.050*
H6B−0.10170.47030.22550.050*
N3−0.0324 (2)0.2849 (2)0.08712 (13)0.0476 (4)
C120.2155 (3)0.5737 (2)0.40604 (14)0.0374 (4)
C130.1314 (2)0.3663 (2)0.10995 (14)0.0367 (4)
C110.2642 (3)0.6790 (2)0.48673 (15)0.0475 (5)
H110.38090.68260.52100.057*
C8−0.0832 (3)0.6682 (3)0.38261 (16)0.0485 (5)
H8−0.19990.66490.34840.058*
C9−0.0374 (4)0.7763 (3)0.46352 (17)0.0574 (6)
H9−0.12260.84630.48240.069*
C100.1326 (4)0.7804 (3)0.51557 (16)0.0560 (6)
H100.16070.85130.57070.067*
C190.5868 (3)0.1738 (2)0.22629 (17)0.0509 (5)
H190.66310.24280.19590.061*
C14−0.0738 (3)0.2269 (3)−0.00667 (18)0.0579 (6)
C180.2619 (3)0.3908 (3)0.04171 (16)0.0532 (5)
H180.37610.44680.06030.064*
C230.3141 (4)0.1170 (3)0.30964 (18)0.0623 (7)
H230.20760.14870.33700.075*
C200.6295 (4)0.0186 (3)0.2303 (2)0.0683 (8)
H200.7366−0.01450.20440.082*
C160.0481 (3)0.2471 (3)−0.07839 (17)0.0590 (6)
H160.01570.2050−0.14270.071*
C210.5141 (5)−0.0834 (3)0.2720 (2)0.0788 (9)
H210.5424−0.18610.27430.095*
C170.2164 (4)0.3297 (3)−0.05363 (18)0.0643 (6)
H170.29960.3444−0.10110.077*
C220.3571 (5)−0.0350 (3)0.3103 (2)0.0821 (9)
H220.2778−0.10600.33730.099*
C15−0.2625 (4)0.1350 (5)−0.0295 (2)0.1035 (13)
H15A−0.32640.13370.02920.155*
H15B−0.24490.0302−0.05420.155*
H15C−0.33520.1830−0.07800.155*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
P10.0327 (3)0.0325 (3)0.0410 (3)0.00243 (18)−0.00086 (19)0.00089 (19)
O40.0493 (8)0.0471 (8)0.0395 (8)0.0155 (6)−0.0083 (6)−0.0055 (6)
N20.0304 (7)0.0421 (8)0.0352 (9)0.0048 (6)0.0018 (6)0.0017 (6)
O50.0364 (7)0.0426 (8)0.0666 (10)−0.0066 (6)0.0011 (6)0.0077 (7)
C240.0403 (9)0.0348 (9)0.0436 (11)0.0058 (8)−0.0026 (8)0.0014 (8)
C70.0374 (9)0.0386 (10)0.0375 (10)0.0015 (7)0.0071 (8)−0.0011 (8)
C60.0314 (9)0.0468 (11)0.0443 (11)0.0041 (8)0.0008 (8)−0.0013 (8)
N30.0411 (9)0.0550 (10)0.0431 (10)0.0014 (8)−0.0024 (7)−0.0079 (8)
C120.0463 (10)0.0331 (9)0.0334 (10)0.0046 (8)0.0040 (8)0.0050 (7)
C130.0382 (9)0.0363 (9)0.0359 (10)0.0084 (7)0.0000 (8)0.0026 (7)
C110.0627 (13)0.0414 (10)0.0362 (11)0.0036 (9)−0.0041 (9)−0.0004 (8)
C80.0484 (11)0.0517 (12)0.0457 (12)0.0094 (9)0.0072 (9)−0.0001 (9)
C90.0735 (15)0.0510 (12)0.0512 (14)0.0206 (11)0.0170 (12)0.0010 (10)
C100.0829 (16)0.0445 (12)0.0380 (12)0.0049 (11)0.0030 (11)−0.0075 (9)
C190.0358 (10)0.0487 (12)0.0645 (15)0.0038 (9)−0.0003 (9)−0.0105 (10)
C140.0526 (12)0.0661 (15)0.0498 (14)0.0071 (11)−0.0090 (10)−0.0133 (11)
C180.0495 (12)0.0642 (14)0.0446 (13)−0.0043 (10)0.0045 (10)0.0051 (10)
C230.0888 (18)0.0445 (12)0.0616 (16)0.0143 (11)0.0293 (13)0.0215 (10)
C200.0558 (14)0.0600 (15)0.083 (2)0.0210 (12)−0.0106 (13)−0.0255 (14)
C160.0659 (14)0.0711 (16)0.0373 (12)0.0153 (12)−0.0047 (10)−0.0099 (11)
C210.115 (2)0.0425 (13)0.076 (2)0.0263 (15)−0.0259 (17)0.0016 (13)
C170.0723 (16)0.0806 (17)0.0402 (13)0.0067 (13)0.0116 (11)0.0021 (12)
C220.130 (3)0.0433 (13)0.079 (2)0.0139 (16)0.0199 (19)0.0209 (13)
C150.0665 (17)0.157 (3)0.070 (2)−0.0246 (19)−0.0090 (15)−0.045 (2)

Geometric parameters (Å, °)

P1—O51.4641 (14)C9—C101.369 (3)
P1—O41.5984 (15)C9—H90.9300
P1—N21.6702 (14)C10—H100.9300
P1—C241.7850 (19)C19—C201.406 (3)
O4—C121.407 (2)C19—H190.9300
N2—C131.424 (2)C14—C161.384 (4)
N2—C61.476 (2)C14—C151.522 (3)
C24—C191.383 (3)C18—C171.372 (3)
C24—C231.388 (3)C18—H180.9300
C7—C121.385 (3)C23—C221.376 (3)
C7—C81.395 (3)C23—H230.9300
C7—C61.491 (3)C20—C211.362 (4)
C6—H6A0.9700C20—H200.9300
C6—H6B0.9700C16—C171.366 (3)
N3—C131.331 (2)C16—H160.9300
N3—C141.342 (3)C21—C221.364 (4)
C12—C111.374 (3)C21—H210.9300
C13—C181.397 (3)C17—H170.9300
C11—C101.397 (3)C22—H220.9300
C11—H110.9300C15—H15A0.9600
C8—C91.388 (3)C15—H15B0.9600
C8—H80.9300C15—H15C0.9600
O5—P1—O4114.90 (8)C8—C9—H9119.9
O5—P1—N2114.95 (8)C9—C10—C11120.7 (2)
O4—P1—N2101.68 (7)C9—C10—H10119.7
O5—P1—C24112.80 (9)C11—C10—H10119.7
O4—P1—C24101.38 (8)C24—C19—C20119.4 (2)
N2—P1—C24109.81 (8)C24—C19—H19120.3
C12—O4—P1121.93 (12)C20—C19—H19120.3
C13—N2—C6116.96 (14)N3—C14—C16122.4 (2)
C13—N2—P1118.81 (12)N3—C14—C15115.9 (2)
C6—N2—P1120.30 (13)C16—C14—C15121.7 (2)
C19—C24—C23119.55 (19)C17—C18—C13117.9 (2)
C19—C24—P1119.92 (16)C17—C18—H18121.0
C23—C24—P1120.53 (16)C13—C18—H18121.0
C12—C7—C8117.29 (17)C22—C23—C24119.7 (2)
C12—C7—C6119.26 (16)C22—C23—H23120.2
C8—C7—C6123.43 (17)C24—C23—H23120.2
N2—C6—C7110.86 (15)C21—C20—C19120.2 (2)
N2—C6—H6A109.5C21—C20—H20119.9
C7—C6—H6A109.5C19—C20—H20119.9
N2—C6—H6B109.5C17—C16—C14119.3 (2)
C7—C6—H6B109.5C17—C16—H16120.4
H6A—C6—H6B108.1C14—C16—H16120.4
C13—N3—C14117.66 (19)C20—C21—C22120.0 (2)
C11—C12—C7123.37 (18)C20—C21—H21120.0
C11—C12—O4119.00 (17)C22—C21—H21120.0
C7—C12—O4117.56 (16)C16—C17—C18119.5 (2)
N3—C13—C18123.22 (18)C16—C17—H17120.2
N3—C13—N2115.42 (16)C18—C17—H17120.2
C18—C13—N2121.35 (17)C21—C22—C23121.2 (3)
C12—C11—C10117.8 (2)C21—C22—H22119.4
C12—C11—H11121.1C23—C22—H22119.4
C10—C11—H11121.1C14—C15—H15A109.5
C9—C8—C7120.6 (2)C14—C15—H15B109.5
C9—C8—H8119.7H15A—C15—H15B109.5
C7—C8—H8119.7C14—C15—H15C109.5
C10—C9—C8120.3 (2)H15A—C15—H15C109.5
C10—C9—H9119.9H15B—C15—H15C109.5
O5—P1—O4—C1288.83 (15)C6—N2—C13—N3−19.5 (2)
N2—P1—O4—C12−35.98 (15)P1—N2—C13—N3138.32 (15)
C24—P1—O4—C12−149.22 (14)C6—N2—C13—C18160.12 (19)
O5—P1—N2—C1367.98 (16)P1—N2—C13—C18−42.1 (2)
O4—P1—N2—C13−167.24 (13)C7—C12—C11—C100.5 (3)
C24—P1—N2—C13−60.47 (16)O4—C12—C11—C10−176.41 (18)
O5—P1—N2—C6−134.97 (14)C12—C7—C8—C90.4 (3)
O4—P1—N2—C6−10.20 (16)C6—C7—C8—C9178.5 (2)
C24—P1—N2—C696.57 (15)C7—C8—C9—C10−1.3 (4)
O5—P1—C24—C19−7.5 (2)C8—C9—C10—C111.7 (4)
O4—P1—C24—C19−130.88 (17)C12—C11—C10—C9−1.3 (3)
N2—P1—C24—C19122.15 (17)C23—C24—C19—C20−2.5 (3)
O5—P1—C24—C23173.33 (17)P1—C24—C19—C20178.29 (17)
O4—P1—C24—C2349.93 (19)C13—N3—C14—C160.9 (3)
N2—P1—C24—C23−57.0 (2)C13—N3—C14—C15−179.9 (2)
C13—N2—C6—C7−156.56 (16)N3—C13—C18—C171.1 (3)
P1—N2—C6—C746.0 (2)N2—C13—C18—C17−178.50 (19)
C12—C7—C6—N2−41.6 (3)C19—C24—C23—C220.9 (4)
C8—C7—C6—N2140.36 (19)P1—C24—C23—C22−179.9 (2)
C8—C7—C12—C11−0.1 (3)C24—C19—C20—C212.2 (4)
C6—C7—C12—C11−178.27 (19)N3—C14—C16—C17−0.4 (4)
C8—C7—C12—O4176.88 (18)C15—C14—C16—C17−179.5 (3)
C6—C7—C12—O4−1.3 (3)C19—C20—C21—C22−0.2 (4)
P1—O4—C12—C11−138.17 (16)C14—C16—C17—C180.1 (4)
P1—O4—C12—C744.7 (2)C13—C18—C17—C16−0.4 (4)
C14—N3—C13—C18−1.3 (3)C20—C21—C22—C23−1.4 (4)
C14—N3—C13—N2178.29 (17)C24—C23—C22—C211.0 (4)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
C17—H17···O5i0.932.573.455 (3)159
C21—H21···O5ii0.932.563.445 (3)159
C18—H18···O50.932.503.158 (3)128

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

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: BH2245).

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