2-Nitro­benzyl diphenyl phosphate

Jin, W.-W.; Chen, C.-B.; Li, X.-Y.

doi:10.1107/S1600536807023379

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2-Nitrobenzyl diphenyl phosphate

W.-W. Jin, C.-B. Chen and X.-Y. Li

In the title compound, C₁₉H₁₆NO₆P, the dihedral angles between the nitrobenzyl ring and the phenyl rings are 53.74 (3) and 63.30 (2)°, and that between the two phenyl rings is 88.86 (3)°. Intermolecular C—H

O hydrogen bonds result in the stabilization of the crystal structure.

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Supporting information

	Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536807023379/fj2030sup1.cif Contains datablocks global, I
	Structure factor file (CIF format) https://doi.org/10.1107/S1600536807023379/fj2030Isup2.hkl Contains datablock I

CCDC reference: 651512

checkCIF report

Key indicators

Single-crystal X-ray study
T = 295 K
Mean (C-C) = 0.003 Å
R factor = 0.037
wR factor = 0.097
Data-to-parameter ratio = 17.2

checkCIF/PLATON results

No syntax errors found



Alert level G
REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is
            correct. If it is not, please give the correct count in the
            _publ_section_exptl_refinement section of the submitted CIF.
           From the CIF: _diffrn_reflns_theta_max           28.00
           From the CIF: _reflns_number_total               4190
           Count of symmetry unique reflns         2322
           Completeness (_total/calc)            180.45%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured      1868
           Fraction of Friedel pairs measured     0.804
           Are heavy atom types Z>Si present        yes
PLAT860_ALERT_3_G Note: Number of Least-Squares Restraints .......          1

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

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

Comment top

Phosphates are extremely useful compounds which have received much attention as genetic materials, co-enzymes and in biochemistry in general. Phosphates have well known roles as intermediates in biochemical transformations (Schick et al., 1995). The title compound (I) is formed by the reaction of diphenylphosphite with an aromatic aldehyde in presence of triethylamine. We also find that the title compound may be obtained from a hydroxyphosphonate rearrangement. In this paper, we present an X-ray crystallographic analysis of (I), shown in Fig. 1. The dihedral angles between the benzene rings A (C1—C6), B (C8—C13) and C (C14—C19) are A/B = 53.74 (3)°, A/C = 63.30 (2)° and B/C = 88.86 (3)°. In the crystal structure, intermolecular C—H···O hydrogen bonds are effective in stabilizing the structure (Fig. 2, Table 2).

Related literature top

For related literature, see: Schick et al. (1995).

Experimental top

To a solution of 2-nitrobenzylaldehyde (1 mmol) in tetrahydrofuran (0.60 ml) was added diphenyl phosphite (1 mmol) at ice-bath temperature. After 15 minutes, triethylamine (0.14 ml) was added, and the reaction mixture was stirred for a further 2 h at ice-bath temperature. The resulting solution was washed with saturated NaHCO₃ solution, extracted with dichloromethane and dried over MgSO₄. The solution was then filtered and purified by column chromatography on silica gel, using ethyl acetate and petroleum as eluant, to afford compound (I).

¹H NMR (CDCl3, 400 MHz): 8.17 (d, J = 8.0 Hz, 1H), 7.73 (d, J = 8.0 Hz, 1H), 7.65 (t, J = 7.6 Hz, 1H), 7.51 (d, J = 8.0 Hz, 1H), 7.35 (t, J = 8.0 Hz, 4H), 7.19–7.26 (m, 6H), 5.74 (d, J = 8.0 Hz, 2H). Crystals suitable for X-ray diffraction were grown from a dichloromethane-ether solution at 298 K.

Structure description top

For related literature, see: Schick et al. (1995).

Computing details top

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

Figures top

	Fig. 1. View of compound (I), showing the atomic labelling scheme. Displacement ellipsoids are drawn at the 50% probability level, and H atoms are represented by circles of arbitrary size.
	Fig. 2. Hydrogen bonding in the crystal structure of (I). Hydrogen bonds are shown as dashed lines.

2-Nitrobenzyl diphenyl phosphate top

Crystal data top

C₁₉H₁₆NO₆P	F(000) = 400
M_r = 385.30	D_x = 1.41 Mg m⁻³
Monoclinic, P2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2yb	Cell parameters from 4390 reflections
a = 6.0641 (5) Å	θ = 2.3–27.1°
b = 8.9176 (8) Å	µ = 0.19 mm⁻¹
c = 16.7851 (14) Å	T = 295 K
β = 90.727 (1)°	Block, colorless
V = 907.62 (13) Å³	0.20 × 0.10 × 0.10 mm
Z = 2

Data collection top

Bruker SMART 4K CCD area-detector diffractometer	3883 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.022
Graphite monochromator	θ_max = 28.0°, θ_min = 2.4°
phi and ω scans	h = −7→7
9691 measured reflections	k = −11→11
4190 independent reflections	l = −21→21

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.037	H-atom parameters constrained
wR(F²) = 0.097	w = 1/[σ²(F_o²) + (0.0618P)² + 0.0077P] where P = (F_o² + 2F_c²)/3
S = 1.05	(Δ/σ)_max = 0.001
4190 reflections	Δρ_max = 0.21 e Å⁻³
244 parameters	Δρ_min = −0.27 e Å⁻³
1 restraint	Absolute structure: Flack (1983), 1868 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.08 (7)

Crystal data top

C₁₉H₁₆NO₆P	V = 907.62 (13) Å³
M_r = 385.30	Z = 2
Monoclinic, P2₁	Mo Kα radiation
a = 6.0641 (5) Å	µ = 0.19 mm⁻¹
b = 8.9176 (8) Å	T = 295 K
c = 16.7851 (14) Å	0.20 × 0.10 × 0.10 mm
β = 90.727 (1)°

Data collection top

Bruker SMART 4K CCD area-detector diffractometer	3883 reflections with I > 2σ(I)
9691 measured reflections	R_int = 0.022
4190 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.037	H-atom parameters constrained
wR(F²) = 0.097	Δρ_max = 0.21 e Å⁻³
S = 1.05	Δρ_min = −0.27 e Å⁻³
4190 reflections	Absolute structure: Flack (1983), 1868 Friedel pairs
244 parameters	Absolute structure parameter: 0.08 (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

	x	y	z	U_iso*/U_eq
C1	1.1681 (3)	0.2682 (3)	0.08864 (11)	0.0471 (4)
C2	1.2298 (4)	0.1344 (3)	0.05385 (12)	0.0595 (6)
H2	1.3592	0.1286	0.0248	0.071*
C3	1.0996 (4)	0.0109 (3)	0.06240 (12)	0.0631 (5)
H3	1.1400	−0.0800	0.0396	0.076*
C4	0.9084 (4)	0.0217 (3)	0.10492 (12)	0.0577 (5)
H4	0.8189	−0.0623	0.1103	0.069*
C5	0.8472 (3)	0.1545 (2)	0.13962 (11)	0.0480 (4)
H5	0.7168	0.1586	0.1681	0.058*
C6	0.9758 (3)	0.2833 (2)	0.13314 (10)	0.0416 (4)
C7	0.9080 (3)	0.4270 (2)	0.17274 (11)	0.0455 (4)
H7A	1.0211	0.4589	0.2104	0.055*
H7B	0.8881	0.5053	0.1332	0.055*
C8	0.5830 (3)	0.8082 (2)	0.26077 (10)	0.0407 (4)
C9	0.3789 (4)	0.8659 (2)	0.24225 (14)	0.0581 (5)
H9	0.2799	0.8122	0.2105	0.070*
C10	0.3237 (4)	1.0049 (3)	0.27156 (16)	0.0709 (6)
H10	0.1863	1.0457	0.2593	0.085*
C11	0.4677 (5)	1.0833 (3)	0.31827 (16)	0.0687 (7)
H11	0.4287	1.1774	0.3374	0.082*
C12	0.6692 (4)	1.0244 (3)	0.33722 (14)	0.0680 (6)
H12	0.7661	1.0780	0.3698	0.082*
C13	0.7307 (3)	0.8847 (2)	0.30818 (12)	0.0536 (5)
H13	0.8682	0.8442	0.3206	0.064*
C14	0.7906 (3)	0.42840 (18)	0.40687 (9)	0.0369 (3)
C15	0.9879 (3)	0.3524 (2)	0.41512 (12)	0.0465 (4)
H15	1.1001	0.3658	0.3785	0.056*
C16	1.0152 (4)	0.2558 (3)	0.47902 (13)	0.0575 (5)
H16	1.1469	0.2035	0.4853	0.069*
C17	0.8504 (4)	0.2363 (2)	0.53315 (13)	0.0554 (5)
H17	0.8708	0.1716	0.5761	0.066*
C18	0.6538 (3)	0.3128 (2)	0.52381 (11)	0.0525 (5)
H18	0.5415	0.2987	0.5603	0.063*
C19	0.6229 (3)	0.4103 (2)	0.46058 (10)	0.0446 (4)
H19	0.4912	0.4627	0.4544	0.054*
N1	1.3160 (3)	0.3970 (2)	0.07554 (10)	0.0561 (4)
O1	1.4834 (3)	0.3768 (3)	0.03849 (12)	0.0898 (6)
O2	1.2634 (3)	0.5195 (2)	0.10143 (10)	0.0750 (4)
O3	0.7011 (2)	0.39994 (15)	0.21402 (8)	0.0467 (3)
O4	0.3803 (2)	0.48193 (15)	0.29503 (8)	0.0497 (3)
O5	0.6448 (2)	0.66933 (14)	0.22804 (7)	0.0467 (3)
O6	0.7736 (2)	0.53291 (14)	0.34462 (7)	0.0445 (3)
P1	0.60419 (7)	0.51722 (5)	0.27268 (2)	0.03749 (11)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0406 (9)	0.0635 (12)	0.0372 (9)	0.0015 (8)	0.0018 (7)	0.0020 (8)
C2	0.0499 (12)	0.0801 (16)	0.0487 (10)	0.0117 (11)	0.0109 (9)	−0.0105 (11)
C3	0.0671 (13)	0.0659 (13)	0.0565 (11)	0.0134 (13)	0.0070 (9)	−0.0201 (11)
C4	0.0644 (12)	0.0523 (10)	0.0566 (10)	−0.0039 (11)	0.0058 (9)	−0.0096 (11)
C5	0.0475 (10)	0.0521 (10)	0.0446 (9)	0.0000 (9)	0.0082 (7)	−0.0051 (8)
C6	0.0389 (9)	0.0503 (10)	0.0357 (8)	0.0020 (7)	0.0016 (6)	−0.0002 (7)
C7	0.0444 (10)	0.0475 (10)	0.0450 (9)	−0.0043 (8)	0.0106 (8)	−0.0042 (8)
C8	0.0481 (10)	0.0353 (8)	0.0387 (8)	0.0004 (7)	0.0039 (7)	0.0063 (7)
C9	0.0539 (12)	0.0493 (11)	0.0709 (13)	0.0040 (9)	−0.0128 (10)	0.0028 (10)
C10	0.0636 (13)	0.0541 (13)	0.0950 (17)	0.0157 (12)	0.0072 (12)	0.0089 (13)
C11	0.0900 (18)	0.0394 (10)	0.0775 (15)	−0.0010 (11)	0.0233 (13)	−0.0038 (10)
C12	0.0841 (16)	0.0547 (12)	0.0652 (12)	−0.0249 (14)	−0.0009 (11)	−0.0077 (13)
C13	0.0475 (11)	0.0555 (12)	0.0577 (11)	−0.0097 (9)	−0.0047 (9)	0.0046 (9)
C14	0.0406 (9)	0.0314 (8)	0.0386 (7)	−0.0039 (6)	−0.0019 (6)	−0.0029 (6)
C15	0.0350 (9)	0.0470 (10)	0.0576 (10)	−0.0027 (8)	0.0038 (8)	0.0022 (8)
C16	0.0446 (11)	0.0514 (11)	0.0761 (15)	0.0056 (9)	−0.0096 (10)	0.0092 (11)
C17	0.0690 (14)	0.0455 (10)	0.0513 (11)	0.0000 (9)	−0.0125 (10)	0.0092 (9)
C18	0.0586 (12)	0.0555 (11)	0.0435 (9)	−0.0019 (9)	0.0080 (8)	0.0018 (9)
C19	0.0430 (10)	0.0440 (9)	0.0470 (9)	0.0055 (7)	0.0054 (7)	−0.0015 (8)
N1	0.0447 (9)	0.0784 (13)	0.0453 (8)	−0.0064 (9)	0.0064 (7)	0.0105 (9)
O1	0.0597 (10)	0.1117 (16)	0.0989 (13)	−0.0036 (10)	0.0374 (10)	0.0141 (12)
O2	0.0738 (10)	0.0738 (10)	0.0778 (10)	−0.0244 (10)	0.0200 (8)	−0.0061 (10)
O3	0.0446 (7)	0.0426 (7)	0.0532 (7)	−0.0040 (5)	0.0128 (6)	−0.0068 (6)
O4	0.0392 (7)	0.0580 (9)	0.0520 (7)	0.0011 (5)	0.0053 (5)	0.0027 (6)
O5	0.0587 (8)	0.0401 (6)	0.0414 (6)	0.0050 (6)	0.0087 (5)	0.0037 (5)
O6	0.0471 (6)	0.0403 (6)	0.0460 (6)	−0.0067 (6)	−0.0018 (5)	0.0079 (6)
P1	0.0378 (2)	0.0362 (2)	0.0386 (2)	0.00156 (19)	0.00463 (15)	0.00116 (18)

Geometric parameters (Å, º) top

C1—C2	1.382 (3)	C11—H11	0.9300
C1—C6	1.399 (2)	C12—C13	1.390 (4)
C1—N1	1.476 (3)	C12—H12	0.9300
C2—C3	1.364 (4)	C13—H13	0.9300
C2—H2	0.9300	C14—C19	1.377 (2)
C3—C4	1.372 (3)	C14—C15	1.381 (3)
C3—H3	0.9300	C14—O6	1.403 (2)
C4—C5	1.373 (3)	C15—C16	1.384 (3)
C4—H4	0.9300	C15—H15	0.9300
C5—C6	1.394 (3)	C16—C17	1.370 (3)
C5—H5	0.9300	C16—H16	0.9300
C6—C7	1.503 (3)	C17—C18	1.381 (3)
C7—O3	1.461 (2)	C17—H17	0.9300
C7—H7A	0.9700	C18—C19	1.383 (3)
C7—H7B	0.9700	C18—H18	0.9300
C8—C13	1.372 (3)	C19—H19	0.9300
C8—C9	1.373 (3)	N1—O1	1.211 (2)
C8—O5	1.408 (2)	N1—O2	1.219 (3)
C9—C10	1.376 (3)	O3—P1	1.5568 (13)
C9—H9	0.9300	O4—P1	1.4475 (14)
C10—C11	1.360 (4)	O5—P1	1.5706 (13)
C10—H10	0.9300	O6—P1	1.5815 (13)
C11—C12	1.363 (4)

C2—C1—C6	122.76 (19)	C11—C12—C13	120.4 (2)
C2—C1—N1	116.14 (17)	C11—C12—H12	119.8
C6—C1—N1	121.10 (19)	C13—C12—H12	119.8
C3—C2—C1	119.48 (18)	C8—C13—C12	118.2 (2)
C3—C2—H2	120.3	C8—C13—H13	120.9
C1—C2—H2	120.3	C12—C13—H13	120.9
C2—C3—C4	119.5 (2)	C19—C14—C15	121.53 (17)
C2—C3—H3	120.3	C19—C14—O6	121.17 (16)
C4—C3—H3	120.3	C15—C14—O6	117.15 (15)
C3—C4—C5	121.1 (2)	C14—C15—C16	118.56 (17)
C3—C4—H4	119.5	C14—C15—H15	120.7
C5—C4—H4	119.5	C16—C15—H15	120.7
C4—C5—C6	121.55 (18)	C17—C16—C15	120.8 (2)
C4—C5—H5	119.2	C17—C16—H16	119.6
C6—C5—H5	119.2	C15—C16—H16	119.6
C5—C6—C1	115.66 (17)	C16—C17—C18	119.84 (19)
C5—C6—C7	120.78 (15)	C16—C17—H17	120.1
C1—C6—C7	123.56 (17)	C18—C17—H17	120.1
O3—C7—C6	108.07 (14)	C17—C18—C19	120.42 (18)
O3—C7—H7A	110.1	C17—C18—H18	119.8
C6—C7—H7A	110.1	C19—C18—H18	119.8
O3—C7—H7B	110.1	C14—C19—C18	118.83 (18)
C6—C7—H7B	110.1	C14—C19—H19	120.6
H7A—C7—H7B	108.4	C18—C19—H19	120.6
C13—C8—C9	121.7 (2)	O1—N1—O2	122.8 (2)
C13—C8—O5	119.27 (17)	O1—N1—C1	118.4 (2)
C9—C8—O5	119.02 (17)	O2—N1—C1	118.81 (16)
C8—C9—C10	118.6 (2)	C7—O3—P1	121.49 (11)
C8—C9—H9	120.7	C8—O5—P1	121.98 (10)
C10—C9—H9	120.7	C14—O6—P1	123.41 (11)
C11—C10—C9	120.8 (2)	O4—P1—O3	112.38 (8)
C11—C10—H10	119.6	O4—P1—O5	117.69 (8)
C9—C10—H10	119.6	O3—P1—O5	102.46 (7)
C10—C11—C12	120.2 (2)	O4—P1—O6	115.06 (7)
C10—C11—H11	119.9	O3—P1—O6	107.19 (8)
C12—C11—H11	119.9	O5—P1—O6	100.58 (7)

C6—C1—C2—C3	0.2 (3)	C15—C16—C17—C18	0.5 (3)
N1—C1—C2—C3	−179.07 (19)	C16—C17—C18—C19	−0.6 (3)
C1—C2—C3—C4	0.5 (3)	C15—C14—C19—C18	−0.4 (3)
C2—C3—C4—C5	−0.6 (3)	O6—C14—C19—C18	−175.85 (17)
C3—C4—C5—C6	0.0 (3)	C17—C18—C19—C14	0.6 (3)
C4—C5—C6—C1	0.6 (3)	C2—C1—N1—O1	−2.7 (3)
C4—C5—C6—C7	−178.93 (18)	C6—C1—N1—O1	177.95 (18)
C2—C1—C6—C5	−0.8 (3)	C2—C1—N1—O2	176.26 (19)
N1—C1—C6—C5	178.51 (17)	C6—C1—N1—O2	−3.1 (3)
C2—C1—C6—C7	178.76 (19)	C6—C7—O3—P1	169.83 (12)
N1—C1—C6—C7	−2.0 (3)	C13—C8—O5—P1	89.90 (19)
C5—C6—C7—O3	0.0 (2)	C9—C8—O5—P1	−92.19 (19)
C1—C6—C7—O3	−179.49 (16)	C19—C14—O6—P1	−67.5 (2)
C13—C8—C9—C10	0.8 (3)	C15—C14—O6—P1	116.86 (16)
O5—C8—C9—C10	−177.09 (18)	C7—O3—P1—O4	168.89 (14)
C8—C9—C10—C11	−0.3 (4)	C7—O3—P1—O5	41.62 (15)
C9—C10—C11—C12	−0.5 (4)	C7—O3—P1—O6	−63.76 (15)
C10—C11—C12—C13	0.9 (4)	C8—O5—P1—O4	56.83 (16)
C9—C8—C13—C12	−0.4 (3)	C8—O5—P1—O3	−179.38 (14)
O5—C8—C13—C12	177.48 (16)	C8—O5—P1—O6	−68.94 (14)
C11—C12—C13—C8	−0.5 (3)	C14—O6—P1—O4	47.55 (15)
C19—C14—C15—C16	0.2 (3)	C14—O6—P1—O3	−78.22 (14)
O6—C14—C15—C16	175.83 (17)	C14—O6—P1—O5	175.07 (13)
C14—C15—C16—C17	−0.2 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C15—H15···O4ⁱ	0.93	2.45	3.344 (2)	162
C7—H7A···O4ⁱ	0.97	2.59	3.537 (2)	164

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

Experimental details

Crystal data
Chemical formula	C₁₉H₁₆NO₆P
M_r	385.30
Crystal system, space group	Monoclinic, P2₁
Temperature (K)	295
a, b, c (Å)	6.0641 (5), 8.9176 (8), 16.7851 (14)
β (°)	90.727 (1)
V (Å³)	907.62 (13)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.19
Crystal size (mm)	0.20 × 0.10 × 0.10

Data collection
Diffractometer	Bruker SMART 4K CCD area-detector diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	9691, 4190, 3883
R_int	0.022
(sin θ/λ)_max (Å⁻¹)	0.661

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.037, 0.097, 1.05
No. of reflections	4190
No. of parameters	244
No. of restraints	1
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.21, −0.27
Absolute structure	Flack (1983), 1868 Friedel pairs
Absolute structure parameter	0.08 (7)

Computer programs: SMART (Bruker, 2001), SAINT (Bruker, 2001), SAINT, SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), PLATON (Spek, 2003), SHELXTL (Bruker, 2001).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C15—H15···O4ⁱ	0.93	2.45	3.344 (2)	162.2
C7—H7A···O4ⁱ	0.97	2.59	3.537 (2)	164.3

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

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