N,N-Dibenzyl-O,O′-dimethyl thio­phosphate

Raissi Shabari, A.; Sabbaghi, F.; Pourayoubi, M.; Nečas, M.; Babiak, M.

doi:10.1107/S1600536812041220

organic compounds

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ISSN: 2056-9890

Volume 68| Part 11| November 2012| Page o3074

doi:10.1107/S1600536812041220

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N,N-Dibenzyl-O,O′-dimethyl thiophosphate

Akbar Raissi Shabari,^a ^* Fahimeh Sabbaghi,^b Mehrdad Pourayoubi,^c Marek Nečas ^d and Michal Babiak ^d

^aFaculty of Chemistry, North Tehran Branch, Islamic Azad University, Tehran, Iran, ^bDepartment of Chemistry, Zanjan Branch, Islamic Azad University, Zanjan, Iran, ^cDepartment of Chemistry, Ferdowsi University of Mashhad, Mashhad, Iran, and ^dDepartment of Chemistry, Faculty of Science, Masaryk University, Kotlarska 2, Brno CZ-61137, Czech Republic
^*Correspondence e-mail: a.raissi_shabari@yahoo.com

(Received 23 September 2012; accepted 1 October 2012; online 6 October 2012)

The P atom in the title compound, C₁₆H₂₀NO₂PS, is bonded in a distorted tetrahedral P(S)(O)₂N environment with the bond angles at the P atom in the range 99.37 (7) to 115.68 (5)°. The angles at the amido N atom (with bond-angle sum of 357.8°) confirm its sp² character. The C—O—P bond angles are 119.78 (11) and 119.39 (12)°.

Related literature

For a related phosphoramidothioate structure, see: Sabbaghi et al. (2012 ). For structures with a P—N(CH₂C₆H₅)₂ fragment, see: Pourayoubi et al. (2012 ).

Experimental

Crystal data

C₁₆H₂₀NO₂PS
M_r = 321.36
Orthorhombic, P 2₁ 2₁ 2₁
a = 6.8377 (3) Å
b = 8.1115 (4) Å
c = 28.6187 (16) Å
V = 1587.31 (14) Å³
Z = 4
Mo Kα radiation
μ = 0.31 mm⁻¹
T = 120 K
0.75 × 0.55 × 0.25 mm

Data collection

Oxford Diffraction Xcalibur Sapphire2 diffractometer
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2009) $[Oxford Diffraction (2009). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Yarnton, England.]$ T_min = 0.802, T_max = 0.927
4397 measured reflections
3010 independent reflections
2747 reflections with I > 2σ(I)
R_int = 0.014

Refinement

R[F² > 2σ(F²)] = 0.027
wR(F²) = 0.064
S = 1.03
3010 reflections
192 parameters
H-atom parameters constrained
Δρ_max = 0.25 e Å⁻³
Δρ_min = −0.31 e Å⁻³
Absolute structure: Flack (1983 ), 982 Friedel pairs
Flack parameter: −0.04 (7)

Data collection: CrysAlis CCD (Oxford Diffraction, 2009 $[Oxford Diffraction (2009). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Yarnton, England.]$ ); cell refinement: CrysAlis CCD; data reduction: CrysAlis RED (Oxford Diffraction, 2009 $[Oxford Diffraction (2009). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Yarnton, England.]$ ); 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 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536812041220/lh5538sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812041220/lh5538Isup2.hkl

checkCIF report

Comment top

The structure determination of the title compound (Fig. 1) was performed as a part of a project on the synthesis of a new phosphoramidothioate (Sabbaghi et al., 2012). The P═S (1.9299 (6) Å), P—O (1.5796 (12) and 1.5961 (12) Å) and P—N (1.6343 (15) Å) bond lengths are within the expected values. The P atom has a distorted tetrahedral configuration (Fig. 1). The bond angles at the P atom vary in the range 99.37 (7) (O1—P1—O2) to 115.68 (5)° (O1—P1—S2). The nitrogen atom shows sp² character with the average bond angle 119.3° with the C—N—C angle (114.98 (13) Å) contracted relative to the P—N—C angles (123.50 (11) and 119.30 (11) Å) similar to previously reported compounds with a P—N(CH₂C₆H₅)₂ fragment (Pourayoubi et al., 2012).

Related literature top

For a related phosphoramidothioate structure, see: Sabbaghi et al. (2012). For a structures with a P—N(CH₂C₆H₅)₂ fragment, see: Pourayoubi et al. (2012).

Experimental top

To a solution of dimethyl chlorothiophosphate, [CH₃O]₂P(S)Cl, (1.7 mmol) in dry CH₃CN (30 ml), a solution of dibenzylamine (3.4 mmol) in the same solvent (5 ml) was added at ice bath temperature. After 4 h stirring, the solvent was removed and the product was washed with distilled water and recrystallized from methanol at room temperature. The single crystals, suitable for X-ray analysis were obtained from this solution after a few days at room temperature.

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2009); cell refinement: CrysAlis CCD (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

Fig. 1. The molecular structure of the title compound with ellipsoids shown at the 50% probability level and H atoms are drawn as small spheres of arbitrary radii.

(I) top

Crystal data top

C₁₆H₂₀NO₂PS	F(000) = 680
M_r = 321.36	D_x = 1.345 Mg m⁻³
Orthorhombic, P2₁2₁2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 2953 reflections
a = 6.8377 (3) Å	θ = 3.1–27.6°
b = 8.1115 (4) Å	µ = 0.31 mm⁻¹
c = 28.6187 (16) Å	T = 120 K
V = 1587.31 (14) Å³	Prism, colourless
Z = 4	0.75 × 0.55 × 0.25 mm

Data collection top

Oxford Diffraction Xcalibur Sapphire2 diffractometer	3010 independent reflections
Radiation source: Enhance (Mo) X-ray Source	2747 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.014
Detector resolution: 8.4353 pixels mm^-1	θ_max = 27.7°, θ_min = 3.1°
ω scan	h = −4→8
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2009)	k = −7→10
T_min = 0.802, T_max = 0.927	l = −18→37
4397 measured reflections

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)] = 0.027	H-atom parameters constrained
wR(F²) = 0.064	w = 1/[σ²(F_o²) + (0.0379P)²] where P = (F_o² + 2F_c²)/3
S = 1.03	(Δ/σ)_max = 0.001
3010 reflections	Δρ_max = 0.25 e Å⁻³
192 parameters	Δρ_min = −0.31 e Å⁻³
0 restraints	Absolute structure: Flack (1983), 982 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: −0.04 (7)

Crystal data top

C₁₆H₂₀NO₂PS	V = 1587.31 (14) Å³
M_r = 321.36	Z = 4
Orthorhombic, P2₁2₁2₁	Mo Kα radiation
a = 6.8377 (3) Å	µ = 0.31 mm⁻¹
b = 8.1115 (4) Å	T = 120 K
c = 28.6187 (16) Å	0.75 × 0.55 × 0.25 mm

Data collection top

Oxford Diffraction Xcalibur Sapphire2 diffractometer	3010 independent reflections
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2009)	2747 reflections with I > 2σ(I)
T_min = 0.802, T_max = 0.927	R_int = 0.014
4397 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.027	H-atom parameters constrained
wR(F²) = 0.064	Δρ_max = 0.25 e Å⁻³
S = 1.03	Δρ_min = −0.31 e Å⁻³
3010 reflections	Absolute structure: Flack (1983), 982 Friedel pairs
192 parameters	Absolute structure parameter: −0.04 (7)
0 restraints

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	−0.1193 (3)	0.0377 (2)	0.26315 (7)	0.0250 (4)
H1A	−0.1339	0.0939	0.2330	0.037*
H1B	−0.2488	0.0089	0.2754	0.037*
H1C	−0.0420	−0.0629	0.2589	0.037*
C2	−0.2073 (3)	−0.0532 (2)	0.40718 (7)	0.0259 (4)
H2A	−0.3466	−0.0609	0.4149	0.039*
H2B	−0.1372	−0.0006	0.4331	0.039*
H2C	−0.1545	−0.1640	0.4020	0.039*
C3	−0.0215 (2)	0.3937 (2)	0.37593 (6)	0.0155 (4)
H3A	−0.1422	0.3714	0.3579	0.019*
H3B	0.0473	0.4869	0.3608	0.019*
C4	0.3118 (2)	0.2750 (2)	0.38807 (6)	0.0150 (4)
H4A	0.3780	0.1672	0.3918	0.018*
H4B	0.3144	0.3312	0.4188	0.018*
C5	−0.0757 (2)	0.4412 (2)	0.42528 (6)	0.0159 (4)
C6	0.0174 (3)	0.5705 (2)	0.44800 (6)	0.0200 (4)
H6	0.1180	0.6297	0.4324	0.024*
C7	−0.0350 (3)	0.6145 (2)	0.49342 (7)	0.0251 (4)
H7	0.0297	0.7031	0.5086	0.030*
C8	−0.1815 (3)	0.5286 (2)	0.51624 (7)	0.0245 (4)
H8	−0.2167	0.5575	0.5473	0.029*
C9	−0.2761 (3)	0.4010 (2)	0.49388 (7)	0.0245 (4)
H9	−0.3773	0.3426	0.5095	0.029*
C10	−0.2240 (3)	0.3574 (2)	0.44868 (6)	0.0200 (4)
H10	−0.2903	0.2695	0.4335	0.024*
C11	0.4258 (2)	0.3774 (2)	0.35330 (6)	0.0157 (4)
C12	0.4820 (3)	0.3088 (2)	0.31086 (6)	0.0189 (4)
H12	0.4468	0.1982	0.3039	0.023*
C13	0.5879 (3)	0.3985 (2)	0.27863 (6)	0.0215 (4)
H13	0.6242	0.3500	0.2497	0.026*
C14	0.6414 (3)	0.5599 (2)	0.28866 (6)	0.0211 (4)
H14	0.7158	0.6217	0.2668	0.025*
C15	0.5860 (3)	0.6299 (2)	0.33044 (7)	0.0223 (4)
H15	0.6212	0.7406	0.3372	0.027*
C16	0.4789 (3)	0.5395 (2)	0.36273 (7)	0.0191 (4)
H16	0.4416	0.5887	0.3915	0.023*
N1	0.1058 (2)	0.24562 (18)	0.37470 (5)	0.0143 (3)
O1	−0.02041 (18)	0.14624 (14)	0.29598 (4)	0.0176 (3)
O2	−0.18301 (17)	0.04395 (15)	0.36533 (4)	0.0186 (3)
P1	0.03212 (6)	0.08173 (5)	0.346520 (16)	0.01436 (11)
S2	0.20827 (7)	−0.10397 (5)	0.348938 (16)	0.02011 (11)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0280 (10)	0.0296 (10)	0.0173 (10)	−0.0001 (9)	−0.0063 (9)	−0.0056 (8)
C2	0.0274 (10)	0.0254 (10)	0.0248 (10)	−0.0004 (9)	0.0074 (9)	0.0080 (8)
C3	0.0169 (8)	0.0151 (8)	0.0145 (9)	0.0038 (8)	−0.0013 (7)	0.0016 (7)
C4	0.0134 (8)	0.0167 (8)	0.0148 (9)	0.0008 (7)	−0.0029 (8)	−0.0013 (7)
C5	0.0153 (8)	0.0151 (9)	0.0174 (9)	0.0069 (7)	−0.0009 (7)	0.0013 (7)
C6	0.0210 (9)	0.0195 (9)	0.0195 (10)	0.0003 (8)	0.0023 (8)	0.0019 (8)
C7	0.0310 (10)	0.0208 (9)	0.0237 (10)	0.0016 (9)	−0.0035 (9)	−0.0038 (8)
C8	0.0299 (10)	0.0295 (10)	0.0141 (9)	0.0086 (9)	0.0025 (9)	−0.0002 (8)
C9	0.0211 (9)	0.0289 (10)	0.0235 (10)	0.0049 (9)	0.0059 (8)	0.0087 (9)
C10	0.0167 (8)	0.0195 (9)	0.0239 (10)	0.0015 (7)	−0.0025 (8)	0.0012 (8)
C11	0.0107 (7)	0.0207 (9)	0.0158 (9)	0.0037 (7)	−0.0026 (7)	0.0025 (8)
C12	0.0164 (8)	0.0226 (9)	0.0177 (10)	0.0013 (8)	−0.0039 (8)	−0.0017 (7)
C13	0.0179 (8)	0.0323 (10)	0.0142 (9)	0.0038 (9)	−0.0017 (7)	0.0013 (9)
C14	0.0145 (8)	0.0267 (10)	0.0221 (10)	0.0019 (8)	−0.0001 (8)	0.0115 (8)
C15	0.0187 (9)	0.0163 (9)	0.0320 (11)	0.0024 (8)	−0.0015 (8)	0.0057 (8)
C16	0.0165 (8)	0.0204 (9)	0.0204 (9)	0.0048 (8)	0.0000 (8)	−0.0005 (8)
N1	0.0125 (6)	0.0175 (7)	0.0130 (8)	0.0033 (6)	−0.0023 (6)	−0.0018 (6)
O1	0.0211 (6)	0.0173 (6)	0.0143 (6)	0.0001 (5)	−0.0030 (6)	−0.0005 (5)
O2	0.0157 (6)	0.0207 (6)	0.0194 (6)	−0.0011 (5)	0.0011 (5)	0.0035 (5)
P1	0.01393 (19)	0.0150 (2)	0.0141 (2)	0.00099 (17)	0.00017 (19)	0.00013 (19)
S2	0.0221 (2)	0.0173 (2)	0.0209 (2)	0.00575 (18)	0.0001 (2)	−0.0006 (2)

Geometric parameters (Å, º) top

C1—O1	1.455 (2)	C7—H7	0.9500
C1—H1A	0.9800	C8—C9	1.378 (3)
C1—H1B	0.9800	C8—H8	0.9500
C1—H1C	0.9800	C9—C10	1.387 (3)
C2—O2	1.443 (2)	C9—H9	0.9500
C2—H2A	0.9800	C10—H10	0.9500
C2—H2B	0.9800	C11—C16	1.390 (2)
C2—H2C	0.9800	C11—C12	1.390 (2)
C3—N1	1.483 (2)	C12—C13	1.380 (3)
C3—C5	1.510 (2)	C12—H12	0.9500
C3—H3A	0.9900	C13—C14	1.390 (3)
C3—H3B	0.9900	C13—H13	0.9500
C4—N1	1.479 (2)	C14—C15	1.377 (3)
C4—C11	1.513 (2)	C14—H14	0.9500
C4—H4A	0.9900	C15—C16	1.389 (3)
C4—H4B	0.9900	C15—H15	0.9500
C5—C6	1.389 (2)	C16—H16	0.9500
C5—C10	1.392 (2)	N1—P1	1.6343 (15)
C6—C7	1.395 (3)	O1—P1	1.5796 (12)
C6—H6	0.9500	O2—P1	1.5961 (12)
C7—C8	1.384 (3)	P1—S2	1.9299 (6)

O1—C1—H1A	109.5	C8—C9—C10	120.25 (18)
O1—C1—H1B	109.5	C8—C9—H9	119.9
H1A—C1—H1B	109.5	C10—C9—H9	119.9
O1—C1—H1C	109.5	C9—C10—C5	120.73 (18)
H1A—C1—H1C	109.5	C9—C10—H10	119.6
H1B—C1—H1C	109.5	C5—C10—H10	119.6
O2—C2—H2A	109.5	C16—C11—C12	118.45 (16)
O2—C2—H2B	109.5	C16—C11—C4	121.75 (16)
H2A—C2—H2B	109.5	C12—C11—C4	119.79 (16)
O2—C2—H2C	109.5	C13—C12—C11	121.18 (18)
H2A—C2—H2C	109.5	C13—C12—H12	119.4
H2B—C2—H2C	109.5	C11—C12—H12	119.4
N1—C3—C5	111.89 (13)	C12—C13—C14	119.78 (18)
N1—C3—H3A	109.2	C12—C13—H13	120.1
C5—C3—H3A	109.2	C14—C13—H13	120.1
N1—C3—H3B	109.2	C15—C14—C13	119.71 (17)
C5—C3—H3B	109.2	C15—C14—H14	120.1
H3A—C3—H3B	107.9	C13—C14—H14	120.1
N1—C4—C11	114.15 (14)	C14—C15—C16	120.36 (17)
N1—C4—H4A	108.7	C14—C15—H15	119.8
C11—C4—H4A	108.7	C16—C15—H15	119.8
N1—C4—H4B	108.7	C15—C16—C11	120.51 (17)
C11—C4—H4B	108.7	C15—C16—H16	119.7
H4A—C4—H4B	107.6	C11—C16—H16	119.7
C6—C5—C10	118.53 (17)	C4—N1—C3	114.98 (13)
C6—C5—C3	121.21 (16)	C4—N1—P1	123.50 (11)
C10—C5—C3	120.26 (17)	C3—N1—P1	119.30 (11)
C5—C6—C7	120.77 (17)	C1—O1—P1	119.78 (11)
C5—C6—H6	119.6	C2—O2—P1	119.39 (12)
C7—C6—H6	119.6	O1—P1—O2	99.37 (7)
C8—C7—C6	119.81 (18)	O1—P1—N1	104.62 (7)
C8—C7—H7	120.1	O2—P1—N1	105.89 (7)
C6—C7—H7	120.1	O1—P1—S2	115.68 (5)
C9—C8—C7	119.91 (18)	O2—P1—S2	114.41 (5)
C9—C8—H8	120.0	N1—P1—S2	115.14 (6)
C7—C8—H8	120.0

N1—C3—C5—C6	101.64 (19)	C12—C11—C16—C15	−0.2 (2)
N1—C3—C5—C10	−79.63 (19)	C4—C11—C16—C15	179.07 (16)
C10—C5—C6—C7	0.6 (3)	C11—C4—N1—C3	−68.76 (18)
C3—C5—C6—C7	179.38 (16)	C11—C4—N1—P1	94.17 (17)
C5—C6—C7—C8	0.0 (3)	C5—C3—N1—C4	−75.77 (18)
C6—C7—C8—C9	−0.6 (3)	C5—C3—N1—P1	120.53 (14)
C7—C8—C9—C10	0.5 (3)	C1—O1—P1—O2	−61.56 (14)
C8—C9—C10—C5	0.1 (3)	C1—O1—P1—N1	−170.81 (13)
C6—C5—C10—C9	−0.7 (3)	C1—O1—P1—S2	61.40 (14)
C3—C5—C10—C9	−179.47 (16)	C2—O2—P1—O1	166.17 (12)
N1—C4—C11—C16	107.68 (18)	C2—O2—P1—N1	−85.59 (14)
N1—C4—C11—C12	−73.1 (2)	C2—O2—P1—S2	42.31 (14)
C16—C11—C12—C13	0.0 (3)	C4—N1—P1—O1	−108.86 (14)
C4—C11—C12—C13	−179.28 (16)	C3—N1—P1—O1	53.38 (13)
C11—C12—C13—C14	0.5 (3)	C4—N1—P1—O2	146.71 (13)
C12—C13—C14—C15	−0.8 (3)	C3—N1—P1—O2	−51.06 (14)
C13—C14—C15—C16	0.7 (3)	C4—N1—P1—S2	19.25 (16)
C14—C15—C16—C11	−0.1 (3)	C3—N1—P1—S2	−178.52 (10)

Experimental details

Crystal data
Chemical formula	C₁₆H₂₀NO₂PS
M_r	321.36
Crystal system, space group	Orthorhombic, P2₁2₁2₁
Temperature (K)	120
a, b, c (Å)	6.8377 (3), 8.1115 (4), 28.6187 (16)
V (Å³)	1587.31 (14)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.31
Crystal size (mm)	0.75 × 0.55 × 0.25

Data collection
Diffractometer	Oxford Diffraction Xcalibur Sapphire2 diffractometer
Absorption correction	Multi-scan (CrysAlis RED; Oxford Diffraction, 2009)
T_min, T_max	0.802, 0.927
No. of measured, independent and observed [I > 2σ(I)] reflections	4397, 3010, 2747
R_int	0.014
(sin θ/λ)_max (Å⁻¹)	0.654

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.027, 0.064, 1.03
No. of reflections	3010
No. of parameters	192
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.25, −0.31
Absolute structure	Flack (1983), 982 Friedel pairs
Absolute structure parameter	−0.04 (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).

Acknowledgements

Support of this investigation by the Islamic Azad University, North Tehran Branch, is gratefully acknowledged.

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