Dimethyl (2-hydr­oxy-4-nitro­benz­yl)phospho­nate

In the title phospho­nate derivative, C₉H₁₂NO₆P, inter­molecular O—H...O hydrogen bonds link the mol­ecules in zigzag chains along the b axis.

Key indicators

• Single-crystal X-ray study
• T = 294 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.040
• wR factor = 0.152
• Data-to-parameter ratio = 15.3

checkCIF/PLATON results

No syntax errors found



Alert level C
GOODF01_ALERT_2_C  The least squares goodness of fit parameter lies
            outside the range 0.80 <> 2.00
            Goodness of fit given =      0.706
PLAT230_ALERT_2_C Hirshfeld Test Diff for    O5     -   N1      ..       5.85 su

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   2 ALERT level C = Check and explain
   0 ALERT level G = General alerts; check

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   2 ALERT type 2 Indicator that the structure model may be wrong or deficient
   0 ALERT type 3 Indicator that the structure quality may be low
   0 ALERT type 4 Improvement, methodology, query or suggestion

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S1. Comment

Phosphonate esters are important intermediates in the preparation of flame-retardant materials (Acher & Wakselman, 1982). As part of our work in this area, the title compound, (I), was prepared by the reaction of 1-bromomethyl-2-hydroxy-4-nitrobenzene and trimethyl phosphite (Grawe et al., 2002) and its structure is reported here (Fig. 1 and Table 1).

The benzene ring and its nitro substituent are essentially coplanar [interplanar angle = 3.4 (2)°], while the O1—P1—O2—C8 and C1—P1—O3—C9 torsion angles are 164.7 (2) and −159.2 (2)°, respectively, indicating that the atoms in these residues are also coplanar. In the crystal structure, O4—H4···O1 hydrogen bonds link the molecules into zigzag chains along the b axis (Fig. 2).

S2. Experimental

The title compound was prepared by the method of Grawe et al. (2002). Single crystals suitable for crystallographic analysis were obtained by slow evaporation of a tetrahydrofuran solution [m.p. 441 (2) K]. IR (KBr, ν, cm⁻¹): 1502 (CN), 1195 (PO). ¹H NMR (DMSO): δ 7.64—7.61 (m, 2H), 7.41–7.39 (m, 1H), 3.61 (s, 3H), 3.58 (s, 3H), 3.31 (s, 1H), 3.27 (s, 1H).

S3. Refinement

All H atoms were refined using a riding model, with C—H = 0.93 Å and U_iso = 1.2U_eq(C) for aromatic H atoms, C—H = 0.97 Å and U_iso = 1.2U_eq(C) for CH₂ H atoms, C—H = 0.96 Å and U_iso = 1.5U_eq(C) for CH₃ H atoms, and O—H = 0.82 Å and U_iso = 1.5U_eq(C) for OH H atoms.

Computing details

Data collection: SMART (Bruker, 1997); cell refinement: SAINT (Bruker, 1997); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 1997); software used to prepare material for publication: SHELXTL.

Figures

	Fig. 1. View of the molecule of (I), showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 50% probability level.
	Fig. 2. Packing of (I), with hydrogen bonds drawn as dashed lines.

Dimethyl (2-hydroxy-4-nitrobenzyl)phosphonate

Crystal data

C9H12NO6P	F(000) = 544
Mr = 261.17	Dx = 1.488 Mg m^−3
Monoclinic, P21/n	Melting point: 441(2) K
Hall symbol: -P 2yn	Mo Kα radiation, λ = 0.71073 Å
a = 7.8154 (15) Å	Cell parameters from 2199 reflections
b = 12.963 (3) Å	θ = 2.4–26.0°
c = 11.669 (2) Å	µ = 0.25 mm^−1
β = 99.660 (3)°	T = 294 K
V = 1165.4 (4) Å^3	Block, yellow
Z = 4	0.30 × 0.24 × 0.12 mm

Data collection

Bruker SMART CCD area-detector diffractometer	2408 independent reflections
Radiation source: fine-focus sealed tube	1671 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.036
ϕ and ω scans	θmax = 26.6°, θmin = 2.4°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −9→8
Tmin = 0.915, Tmax = 0.972	k = −16→15
6476 measured reflections	l = −12→14

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.040	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.152	H-atom parameters constrained
S = 0.71	w = 1/[σ^2(Fo^2) + (0.1314P)^2 + 1.0878P] where P = (Fo^2 + 2Fc^2)/3
2408 reflections	(Δ/σ)max = 0.002
157 parameters	Δρmax = 0.19 e Å^−3
0 restraints	Δρmin = −0.38 e Å^−3

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 (Ų)

	x	y	z	Uiso*/Ueq
P1	0.08647 (8)	0.30331 (5)	0.10575 (5)	0.0373 (2)
O1	0.0878 (3)	0.19508 (13)	0.14275 (16)	0.0491 (5)
O2	0.2783 (2)	0.34014 (15)	0.11173 (16)	0.0521 (5)
O3	−0.0138 (3)	0.32433 (14)	−0.01981 (16)	0.0542 (5)
O4	0.1995 (3)	0.54684 (14)	0.27178 (16)	0.0551 (5)
H4	0.2660	0.5917	0.3023	0.083*
O5	0.3644 (3)	0.50764 (18)	0.69912 (17)	0.0663 (6)
O6	0.2441 (3)	0.3662 (2)	0.74030 (18)	0.0750 (7)
N1	0.2764 (3)	0.4313 (2)	0.67091 (19)	0.0500 (6)
C1	−0.0239 (4)	0.3876 (2)	0.1893 (2)	0.0461 (6)
H1A	−0.0284	0.4559	0.1549	0.055*
H1B	−0.1424	0.3636	0.1849	0.055*
C2	0.0590 (3)	0.39558 (18)	0.3161 (2)	0.0385 (6)
C3	0.0249 (3)	0.3239 (2)	0.3975 (2)	0.0470 (6)
H3	−0.0476	0.2684	0.3732	0.056*
C4	0.0963 (4)	0.3330 (2)	0.5145 (2)	0.0476 (6)
H4A	0.0729	0.2846	0.5686	0.057*
C5	0.2028 (3)	0.4161 (2)	0.5471 (2)	0.0396 (6)
C6	0.2428 (3)	0.48830 (18)	0.4697 (2)	0.0382 (5)
H6	0.3168	0.5429	0.4949	0.046*
C7	0.1703 (3)	0.47825 (17)	0.3528 (2)	0.0377 (5)
C8	0.3249 (5)	0.4333 (3)	0.0558 (3)	0.0708 (10)
H8A	0.3273	0.4195	−0.0248	0.106*
H8B	0.4374	0.4561	0.0930	0.106*
H8C	0.2408	0.4861	0.0620	0.106*
C9	−0.0114 (4)	0.2514 (2)	−0.1127 (2)	0.0515 (7)
H9A	0.1066	0.2354	−0.1189	0.077*
H9B	−0.0687	0.2808	−0.1845	0.077*
H9C	−0.0706	0.1895	−0.0966	0.077*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
P1	0.0421 (4)	0.0322 (4)	0.0352 (4)	0.0033 (3)	−0.0001 (3)	−0.0009 (2)
O1	0.0642 (13)	0.0326 (10)	0.0500 (11)	0.0039 (8)	0.0078 (9)	0.0009 (8)
O2	0.0445 (11)	0.0596 (12)	0.0517 (11)	−0.0017 (9)	0.0069 (9)	0.0090 (9)
O3	0.0706 (13)	0.0463 (11)	0.0381 (10)	0.0097 (9)	−0.0128 (9)	−0.0051 (8)
O4	0.0796 (15)	0.0397 (10)	0.0405 (10)	−0.0087 (9)	−0.0055 (9)	0.0034 (8)
O5	0.0774 (15)	0.0716 (14)	0.0436 (11)	−0.0038 (12)	−0.0078 (10)	−0.0119 (10)
O6	0.0745 (15)	0.1102 (19)	0.0423 (11)	−0.0030 (14)	0.0157 (10)	0.0188 (12)
N1	0.0474 (13)	0.0667 (15)	0.0368 (12)	0.0145 (12)	0.0099 (10)	0.0016 (11)
C1	0.0431 (14)	0.0439 (14)	0.0467 (15)	0.0072 (11)	−0.0057 (11)	−0.0094 (11)
C2	0.0355 (12)	0.0376 (13)	0.0412 (13)	0.0072 (10)	0.0032 (10)	−0.0089 (10)
C3	0.0420 (14)	0.0447 (14)	0.0546 (16)	−0.0063 (11)	0.0094 (12)	−0.0100 (12)
C4	0.0497 (16)	0.0451 (14)	0.0512 (16)	−0.0018 (12)	0.0175 (13)	0.0039 (12)
C5	0.0366 (13)	0.0457 (14)	0.0370 (13)	0.0070 (10)	0.0077 (10)	−0.0049 (10)
C6	0.0405 (13)	0.0328 (12)	0.0402 (13)	0.0026 (10)	0.0030 (10)	−0.0055 (10)
C7	0.0435 (13)	0.0313 (12)	0.0370 (12)	0.0069 (10)	0.0027 (10)	−0.0025 (10)
C8	0.084 (2)	0.074 (2)	0.0568 (19)	−0.0265 (19)	0.0164 (17)	0.0059 (16)
C9	0.0664 (19)	0.0530 (17)	0.0350 (13)	−0.0104 (14)	0.0082 (12)	−0.0048 (11)

Geometric parameters (Å, º)

P1—O1	1.4673 (19)	C2—C7	1.401 (3)
P1—O2	1.563 (2)	C3—C4	1.390 (4)
P1—O3	1.5653 (18)	C3—H3	0.9300
P1—C1	1.781 (3)	C4—C5	1.376 (4)
O2—C8	1.449 (4)	C4—H4A	0.9300
O3—C9	1.441 (3)	C5—C6	1.372 (4)
O4—C7	1.345 (3)	C6—C7	1.392 (3)
O4—H4	0.8200	C6—H6	0.9300
O5—N1	1.219 (3)	C8—H8A	0.9600
O6—N1	1.225 (3)	C8—H8B	0.9600
N1—C5	1.476 (3)	C8—H8C	0.9600
C1—C2	1.516 (3)	C9—H9A	0.9600
C1—H1A	0.9700	C9—H9B	0.9600
C1—H1B	0.9700	C9—H9C	0.9600
C2—C3	1.386 (4)
O1—P1—O2	108.62 (11)	C5—C4—C3	117.5 (2)
O1—P1—O3	114.82 (11)	C5—C4—H4A	121.2
O2—P1—O3	108.33 (11)	C3—C4—H4A	121.2
O1—P1—C1	113.95 (13)	C6—C5—C4	123.1 (2)
O2—P1—C1	109.70 (12)	C6—C5—N1	117.3 (2)
O3—P1—C1	101.12 (12)	C4—C5—N1	119.6 (2)
C8—O2—P1	123.1 (2)	C5—C6—C7	118.7 (2)
C9—O3—P1	121.49 (18)	C5—C6—H6	120.6
C7—O4—H4	109.5	C7—C6—H6	120.6
O5—N1—O6	123.4 (2)	O4—C7—C6	122.5 (2)
O5—N1—C5	118.8 (2)	O4—C7—C2	117.4 (2)
O6—N1—C5	117.8 (3)	C6—C7—C2	120.1 (2)
C2—C1—P1	114.14 (17)	O2—C8—H8A	109.5
C2—C1—H1A	108.7	O2—C8—H8B	109.5
P1—C1—H1A	108.7	H8A—C8—H8B	109.5
C2—C1—H1B	108.7	O2—C8—H8C	109.5
P1—C1—H1B	108.7	H8A—C8—H8C	109.5
H1A—C1—H1B	107.6	H8B—C8—H8C	109.5
C3—C2—C7	118.9 (2)	O3—C9—H9A	109.5
C3—C2—C1	121.6 (2)	O3—C9—H9B	109.5
C7—C2—C1	119.5 (2)	H9A—C9—H9B	109.5
C2—C3—C4	121.7 (2)	O3—C9—H9C	109.5
C2—C3—H3	119.2	H9A—C9—H9C	109.5
C4—C3—H3	119.2	H9B—C9—H9C	109.5
O1—P1—O2—C8	164.7 (2)	C3—C4—C5—C6	−1.0 (4)
O3—P1—O2—C8	39.4 (2)	C3—C4—C5—N1	177.7 (2)
C1—P1—O2—C8	−70.2 (3)	O5—N1—C5—C6	2.0 (3)
O1—P1—O3—C9	−36.1 (3)	O6—N1—C5—C6	−178.7 (2)
O2—P1—O3—C9	85.5 (2)	O5—N1—C5—C4	−176.8 (2)
C1—P1—O3—C9	−159.2 (2)	O6—N1—C5—C4	2.5 (4)
O1—P1—C1—C2	63.8 (2)	C4—C5—C6—C7	1.1 (4)
O2—P1—C1—C2	−58.3 (2)	N1—C5—C6—C7	−177.7 (2)
O3—P1—C1—C2	−172.52 (19)	C5—C6—C7—O4	178.4 (2)
P1—C1—C2—C3	−83.8 (3)	C5—C6—C7—C2	0.0 (3)
P1—C1—C2—C7	97.4 (2)	C3—C2—C7—O4	−179.5 (2)
C7—C2—C3—C4	0.9 (4)	C1—C2—C7—O4	−0.7 (3)
C1—C2—C3—C4	−177.8 (2)	C3—C2—C7—C6	−0.9 (4)
C2—C3—C4—C5	0.0 (4)	C1—C2—C7—C6	177.9 (2)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O4—H4···O1^i	0.82	1.81	2.625 (3)	175

Symmetry code: (i) −x+1/2, y+1/2, −z+1/2.