Diethyl hydr­oxy(4-methoxy­phen­yl)methyl­phospho­nate

The title compound, C₁₂H₁₉O₅P, was obtained by the reaction of 4-methoxy­benzaldehyde and diethyl phospho­nate. Inter­molecular O—H...O hydrogen bonds between the phosphoryl O atom and the hydr­oxy group result in the formation of an infinite chain connecting the mol­ecules along the b axis.

Key indicators

• Single-crystal X-ray study
• T = 273 K
• Mean [sigma](C-C) = 0.005 Å
• R factor = 0.064
• wR factor = 0.159
• Data-to-parameter ratio = 17.7

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT241_ALERT_2_B Check High      Ueq as Compared to Neighbors for         C8
PLAT360_ALERT_2_B Short  C(sp3)-C(sp3) Bond  C8     -   C10    ...       1.31 Ang.

Alert level C
PLAT066_ALERT_1_C Predicted and Reported Transmissions Identical .          ?
PLAT220_ALERT_2_C Large Non-Solvent    C     Ueq(max)/Ueq(min) ...       2.86 Ratio
PLAT222_ALERT_3_C Large Non-Solvent    H     Ueq(max)/Ueq(min) ...       3.07 Ratio
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for         O3
PLAT340_ALERT_3_C Low Bond Precision on C-C Bonds (x 1000) Ang ...          5
PLAT360_ALERT_2_C Short  C(sp3)-C(sp3) Bond  C9     -   C11    ...       1.42 Ang.

Alert level G
PLAT793_ALERT_1_G Check the Absolute Configuration of C1     = ...          S

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

   2 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   5 ALERT type 2 Indicator that the structure model may be wrong or deficient
   2 ALERT type 3 Indicator that the structure quality may be low
   0 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

---

S1. Comment

In recent years \a-hydroxyphosphonic acids esters have attracted much attention due to their wide biological activity (Stowasser et al., 1992) and pharmaceutical interest (Chen et al., 1995). They are useful reagents for the synthesis of enol ethers and \a-ketophosphonates (Babak et al., 2001). Bond lengths and angles in the title compound, (I), are in agreement with the values reported for related compounds (Smaardijk et al., 1985). Intermolecular O—H···O hydrogen bond between the phosphoryl O atom and the hydroxy group results in the formation of an infinite chain connecting the molecules along the b axis (Table 1 and Fig. 3).

Related literature

For related literature, see: Babak & Rahman (2001); Chen et al. (1995); Martine et al. (1995); Smaardijk et al. (1985); Stowasser et al. (1992).

S2. Experimental

To a solution of 4-methoxybenzaldehyde (5 mmol, 0.68 g) and diethyl phosphonate (5 mmol, 0.69 g) in tetrahydrofuran (5 ml) at 0 \%C was added aqueous ammonia (25%, 1.6 ml). The mixture was left to stand at ambient temperature for 2 h, during which time a precipitate separated. The precipitate was filtered off and washed rapidly with cold diethyl ether (Martine et al., 1995). Single crystals were obtained by crystallization of a dichloromethane/ petroleum ether (v/v = 1/4) solution (Fig. 1). CHN analysis, calculated for C~12~H~19Õ~5~P: C, 52.55%; H, 6.98%; Found: C, 52.41%; H, 6.96%.

S3. Refinement

All H atoms were placed in geometrically idealized positions and treated as riding on their parent atoms, with C—H = 0.93 (aromatic), 0.96 (CH₃), 0.97 (CH₂) or 0.98 (CH), O—H = 0.82 \%A and U_iso(H) = 1.2U_eq (aromatic C, CH and CH₂) or 1.5U_eq (methyl C and O).

Computing details

Data collection: SMART (Bruker, 2001); cell refinement: SAINT (Bruker, 2001); data reduction: SAINT (Bruker, 2001); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2003); software used to prepare material for publication: SHELXL97.

Figures

	Fig. 1. Reaction scheme.
	Fig. 2. Molecular view of I with the atom-numbering scheme. Displacement ellipsoids are drawn atthe 30% probability level. H atoms are represented as small spheres of arbitrary radii.
	Fig. 3. Packing diagram of title compound showing the O—H···O interactions as dashed lines. The H atoms not involved in hydrogen bonding have been omitted. [Symmetry code: (i) -x + 1/2, y + 1/2, -z + 1/2)]

diethyl hydroxy(4-methoxyphenyl)methylphosphonate

Crystal data

C12H19O5P	F(000) = 584
Mr = 274.24	Dx = 1.294 Mg m^−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 1884 reflections
a = 10.454 (4) Å	θ = 2.6–25.1°
b = 7.745 (3) Å	µ = 0.21 mm^−1
c = 18.021 (7) Å	T = 273 K
β = 105.228 (7)°	Block, colourless
V = 1407.8 (9) Å^3	0.30 × 0.20 × 0.18 mm
Z = 4

Data collection

Bruker APEX area-detector diffractometer	2891 independent reflections
Radiation source: fine-focus sealed tube	1818 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.068
φ and ω scan	θmax = 26.5°, θmin = 2.1°
Absorption correction: multi-scan (SADABS; Bruker, 2001)	h = −12→13
Tmin = 0.941, Tmax = 0.964	k = −9→9
7612 measured reflections	l = −18→22

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)] = 0.065	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.159	H-atom parameters constrained
S = 1.06	w = 1/[σ^2(Fo^2) + (0.0544P)^2 + 0.210P] where P = (Fo^2 + 2Fc^2)/3
2891 reflections	(Δ/σ)max < 0.001
163 parameters	Δρmax = 0.34 e Å^−3
0 restraints	Δρmin = −0.23 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	0.14301 (7)	0.22551 (10)	0.12858 (4)	0.0579 (3)
C1	0.1690 (2)	0.3440 (4)	0.21623 (17)	0.0585 (8)
H1A	0.1783	0.4665	0.2051	0.070*
O1	0.29092 (16)	0.2847 (3)	0.26315 (12)	0.0686 (6)
H1B	0.3220	0.3574	0.2960	0.103*
C2	0.0569 (2)	0.3249 (3)	0.25236 (16)	0.0538 (7)
O2	0.12622 (17)	0.0406 (2)	0.13491 (10)	0.0610 (5)
O3	0.2581 (2)	0.2753 (3)	0.09399 (13)	0.0794 (7)
C3	0.0574 (3)	0.2032 (4)	0.30721 (17)	0.0631 (8)
H3A	0.1283	0.1268	0.3217	0.076*
O4	0.0233 (2)	0.3229 (3)	0.07794 (13)	0.0766 (6)
C4	−0.0443 (3)	0.1923 (4)	0.34103 (18)	0.0711 (9)
H4A	−0.0413	0.1103	0.3792	0.085*
O5	−0.2459 (2)	0.2769 (3)	0.35739 (14)	0.0913 (8)
C5	−0.1500 (3)	0.2997 (4)	0.31971 (18)	0.0643 (8)
C6	−0.1545 (3)	0.4176 (5)	0.2642 (2)	0.0738 (9)
H6A	−0.2276	0.4898	0.2483	0.089*
C7	−0.0514 (3)	0.4306 (4)	0.23163 (19)	0.0683 (8)
H7A	−0.0547	0.5139	0.1940	0.082*
C8	0.3671 (5)	0.1724 (7)	0.0963 (4)	0.154 (2)
H8A	0.4157	0.1605	0.1499	0.185*
H8B	0.3342	0.0585	0.0785	0.185*
C9	−0.0663 (4)	0.2564 (5)	0.0107 (2)	0.1039 (13)
H9A	−0.0628	0.1312	0.0115	0.125*
H9B	−0.0407	0.2960	−0.0344	0.125*
C10	0.4525 (5)	0.2167 (7)	0.0581 (3)	0.143 (2)
H10B	0.5230	0.1335	0.0672	0.215*
H10C	0.4883	0.3284	0.0750	0.215*
H10D	0.4089	0.2206	0.0042	0.215*
C11	−0.1979 (4)	0.3120 (7)	0.0065 (3)	0.142 (2)
H11A	−0.2576	0.2658	−0.0390	0.214*
H11B	−0.2016	0.4359	0.0048	0.214*
H11C	−0.2233	0.2719	0.0510	0.214*
C12	−0.3571 (3)	0.3881 (6)	0.3378 (3)	0.1105 (14)
H12A	−0.4172	0.3592	0.3681	0.166*
H12B	−0.4012	0.3751	0.2842	0.166*
H12C	−0.3283	0.5055	0.3479	0.166*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
P1	0.0565 (5)	0.0514 (5)	0.0661 (5)	0.0027 (4)	0.0168 (4)	0.0044 (4)
C1	0.0453 (15)	0.0469 (17)	0.081 (2)	−0.0007 (13)	0.0119 (14)	−0.0014 (14)
O1	0.0438 (11)	0.0669 (14)	0.0886 (15)	0.0018 (9)	0.0057 (10)	−0.0180 (11)
C2	0.0452 (15)	0.0466 (17)	0.0645 (18)	0.0029 (12)	0.0056 (13)	−0.0098 (13)
O2	0.0687 (12)	0.0461 (12)	0.0671 (13)	−0.0026 (9)	0.0157 (10)	−0.0039 (9)
O3	0.0787 (14)	0.0681 (15)	0.1036 (18)	0.0080 (12)	0.0456 (13)	0.0170 (12)
C3	0.0542 (17)	0.067 (2)	0.0642 (19)	0.0183 (15)	0.0087 (15)	−0.0023 (15)
O4	0.0772 (14)	0.0683 (16)	0.0764 (15)	0.0111 (11)	0.0065 (12)	0.0024 (11)
C4	0.0676 (19)	0.078 (2)	0.070 (2)	0.0145 (17)	0.0220 (17)	0.0075 (16)
O5	0.0689 (14)	0.116 (2)	0.0976 (18)	0.0117 (14)	0.0382 (13)	−0.0108 (14)
C5	0.0498 (17)	0.077 (2)	0.066 (2)	0.0040 (16)	0.0162 (15)	−0.0154 (17)
C6	0.0543 (17)	0.075 (2)	0.090 (2)	0.0214 (16)	0.0157 (17)	−0.0023 (19)
C7	0.0574 (17)	0.057 (2)	0.090 (2)	0.0149 (15)	0.0186 (16)	0.0101 (16)
C8	0.111 (3)	0.140 (5)	0.249 (7)	0.039 (3)	0.114 (4)	0.073 (4)
C9	0.109 (3)	0.098 (3)	0.086 (3)	0.014 (2)	−0.009 (2)	−0.010 (2)
C10	0.126 (4)	0.155 (5)	0.172 (5)	0.025 (4)	0.082 (4)	0.017 (4)
C11	0.089 (3)	0.140 (5)	0.163 (5)	0.002 (3)	−0.030 (3)	0.025 (4)
C12	0.067 (2)	0.129 (4)	0.147 (4)	0.020 (2)	0.049 (2)	−0.025 (3)

Geometric parameters (Å, º)

P1—O2	1.451 (2)	C6—C7	1.359 (4)
P1—O4	1.539 (2)	C6—H6A	0.9300
P1—O3	1.543 (2)	C7—H7A	0.9300
P1—C1	1.785 (3)	C8—C10	1.308 (5)
C1—O1	1.408 (3)	C8—H8A	0.9700
C1—C2	1.490 (4)	C8—H8B	0.9700
C1—H1A	0.9800	C9—C11	1.425 (5)
O1—H1B	0.8200	C9—H9A	0.9700
C2—C3	1.364 (4)	C9—H9B	0.9700
C2—C7	1.367 (4)	C10—H10B	0.9600
O3—C8	1.382 (4)	C10—H10C	0.9600
C3—C4	1.360 (4)	C10—H10D	0.9600
C3—H3A	0.9300	C11—H11A	0.9600
O4—C9	1.420 (4)	C11—H11B	0.9600
C4—C5	1.356 (4)	C11—H11C	0.9600
C4—H4A	0.9300	C12—H12A	0.9600
O5—C5	1.362 (3)	C12—H12B	0.9600
O5—C12	1.415 (4)	C12—H12C	0.9600
C5—C6	1.346 (5)
O2—P1—O4	115.73 (12)	C6—C7—H7A	119.0
O2—P1—O3	113.70 (12)	C2—C7—H7A	119.0
O4—P1—O3	103.71 (13)	C10—C8—O3	120.3 (4)
O2—P1—C1	115.56 (13)	C10—C8—H8A	107.3
O4—P1—C1	100.60 (13)	O3—C8—H8A	107.3
O3—P1—C1	105.98 (13)	C10—C8—H8B	107.3
O1—C1—C2	113.4 (2)	O3—C8—H8B	107.3
O1—C1—P1	105.49 (18)	H8A—C8—H8B	106.9
C2—C1—P1	112.39 (18)	O4—C9—C11	110.3 (3)
O1—C1—H1A	108.5	O4—C9—H9A	109.6
C2—C1—H1A	108.5	C11—C9—H9A	109.6
P1—C1—H1A	108.5	O4—C9—H9B	109.6
C1—O1—H1B	109.5	C11—C9—H9B	109.6
C3—C2—C7	117.2 (3)	H9A—C9—H9B	108.1
C3—C2—C1	122.1 (2)	C8—C10—H10B	109.5
C7—C2—C1	120.7 (3)	C8—C10—H10C	109.5
C8—O3—P1	124.6 (2)	H10B—C10—H10C	109.5
C4—C3—C2	120.8 (3)	C8—C10—H10D	109.5
C4—C3—H3A	119.6	H10B—C10—H10D	109.5
C2—C3—H3A	119.6	H10C—C10—H10D	109.5
C9—O4—P1	125.4 (2)	C9—C11—H11A	109.5
C5—C4—C3	120.6 (3)	C9—C11—H11B	109.5
C5—C4—H4A	119.7	H11A—C11—H11B	109.5
C3—C4—H4A	119.7	C9—C11—H11C	109.5
C5—O5—C12	117.4 (3)	H11A—C11—H11C	109.5
C6—C5—C4	119.6 (3)	H11B—C11—H11C	109.5
C6—C5—O5	124.9 (3)	O5—C12—H12A	109.5
C4—C5—O5	115.5 (3)	O5—C12—H12B	109.5
C5—C6—C7	119.6 (3)	H12A—C12—H12B	109.5
C5—C6—H6A	120.2	O5—C12—H12C	109.5
C7—C6—H6A	120.2	H12A—C12—H12C	109.5
C6—C7—C2	122.1 (3)	H12B—C12—H12C	109.5
O2—P1—C1—O1	64.4 (2)	O2—P1—O4—C9	−33.9 (3)
O4—P1—C1—O1	−170.20 (17)	O3—P1—O4—C9	91.3 (3)
O3—P1—C1—O1	−62.5 (2)	C1—P1—O4—C9	−159.2 (3)
O2—P1—C1—C2	−59.6 (2)	C2—C3—C4—C5	1.5 (5)
O4—P1—C1—C2	65.8 (2)	C3—C4—C5—C6	0.4 (5)
O3—P1—C1—C2	173.50 (19)	C3—C4—C5—O5	179.9 (3)
O1—C1—C2—C3	−25.5 (4)	C12—O5—C5—C6	−1.5 (5)
P1—C1—C2—C3	94.0 (3)	C12—O5—C5—C4	179.0 (3)
O1—C1—C2—C7	154.2 (3)	C4—C5—C6—C7	−1.7 (5)
P1—C1—C2—C7	−86.3 (3)	O5—C5—C6—C7	178.8 (3)
O2—P1—O3—C8	−24.8 (4)	C5—C6—C7—C2	1.2 (5)
O4—P1—O3—C8	−151.3 (4)	C3—C2—C7—C6	0.6 (4)
C1—P1—O3—C8	103.2 (4)	C1—C2—C7—C6	−179.2 (3)
C7—C2—C3—C4	−1.9 (4)	P1—O3—C8—C10	172.4 (4)
C1—C2—C3—C4	177.8 (3)	P1—O4—C9—C11	142.0 (3)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1B···O2^i	0.82	1.87	2.687 (3)	173

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