N-(3,5-Di­methyl­phen­yl)-P,P-di­phenyl­phosphinic amide

Khojandi, N.; Rath, N.P.; Jones, M.W.

doi:10.1107/S2414314618011926

organic compounds

IUCrDATA

ISSN: 2414-3146

Volume 3| Part 8| August 2018| x181192

https://doi.org/10.1107/S2414314618011926

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N-(3,5-Dimethylphenyl)-P,P-diphenylphosphinic amide

Niloufar Khojandi,^a Nigam P. Rath ^b and Myron W. Jones ^a ^*

^aDepartment of Chemistry, Southern Illinois University Edwardsville, Edwardsville, IL 62026-1652, USA, and ^bDepartment of Chemistry and Biochemistry, and Center of Nanoscience, University of Missouri-St. Louis, St. Louis, MO 63121-4400, USA
^*Correspondence e-mail: myrjone@siue.edu

Edited by W. T. A. Harrison, University of Aberdeen, Scotland (Received 21 August 2018; accepted 22 August 2018; online 31 August 2018)

In the title compound, C₂₀H₂₀NOP, the P atom, with a distorted tetrahedral geometry, is attached to an O atom, two phenyl groups, and a 3,5-dimethylaniline group. The N—P—C [102.29 (12) and 108.97 (12)°] and C—P—C [107.14 (12)°] bond angles are all smaller than the ideal 109.5° tetrahedral bond angle, whereas the O—P—C [113.07 (12) and 110.62 (12)°] and O—P—N [114.24 (13)°] angles are all larger than 109.5°. A weak intramolecular C—H⋯O hydrogen bond helps to establish the molecular conformation. In the crystal, the molecules are linked by N—H⋯O hydrogen bonds, generating [001] chains.

Keywords: crystal structure; hydrogen bonding; phosphinamide.

CCDC reference: 1863429

Structure description

Phosphinamide derivatives have applications as ligands in transition and rare earth metal chemistry and in catalysis (Priya et al., 2005 ; Gusev et al., 2009 ; Naktode et al., 2012 ; Naktode et al., 2013 ; Sun & Cramer, 2017 ) and are of general synthetic interest, particularly in the pharmaceutical field (Xu et al., 2017 ; Hong et al., 2016 ). As part of our studies in this area, the title compound was serendipitously isolated and its structure is reported here. Structures for the [Ph₂P(O)NH(2,6-(CH₃)₂(C₆H₃)] structural isomer (Naktode et al., 2012) and related [Ph₂P(O)NHPh] (Priya et al., 2005) are known.

The molecular structure of the title compound is shown in Fig. 1. The phosphorus atom exhibits slightly distorted tetrahedral geometry. The four P—X bonds [X = O:1.477 (2), N:1.653 (2), C:1.797 (3) and 1.803 (3) Å] are similar to those found in [Ph₂P(O)NH(2,6-(CH₃)₂(C₆H₃)] and [Ph₂P(O)NHPh] as are the bond angles about the phosphorus atom. The N—P—C [102.29 (12) and 108.97 (12)°] and C—P—C [107.14 (12)°] angles are all slightly smaller than the ideal 109.5° bond angle for tetrahedral geometry, while the O—P—C [113.07 (12) and 110.62 (12)°] and O—P—N [114.24 (13)°] bond angles are all larger than 109.5°. The N—H and P—O bonds are anti to each other, which facilitates the formation of an [001] chain of N—H⋯O hydrogen bonds (Table 1) in the crystal (Fig. 2). An intramolecular C—H⋯O hydrogen bond in each molecule helps to position the ring.

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C2—H2⋯O1	0.95	2.48	3.148 (3)	128
N1—H1⋯O1ⁱ	0.88	2.12	2.788 (3)	133
Symmetry code: (i) $[-x+{\script{3\over 2}}, y, z+{\script{1\over 2}}]$ .

Figure 1
Molecular structure of [Ph₂P(O)NH(3,5-(CH₃)₂(C₆H₃)] with displacement ellipsoids drawn at the 50% probability level.

Figure 2
Unit-cell packing viewed along the b axis showing N—H⋯O hydrogen-bonding contacts as dotted lines.

Synthesis and crystallization

The title compound was obtained during our attempt to crystallize [(Ph₂P)₂N(3,5-(CH₃)₂(C₆H₃)], which had been prepared by a literature method (Shozi & Friedrich, 2012 ). A dichloromethane solution of [(Ph₂P)₂N(3,5-(CH₃)₂(C₆H₃)] was allowed to evaporate slowly at room temperature under argon. After 24 h, crystals suitable for single-crystal structure determination were obtained. However, [Ph₂P(O)NH(3,5-(CH₃)₂(C₆H₃)] rather than the expected [(Ph₂P)₂N(3,5-(CH₃)₂(C₆H₃)] was serendipitously isolated. The title compound may have formed as a result of the adventitious exposure of the sample to moisture and/or oxygen.

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2.

Table 2
Experimental details

Crystal data
Chemical formula	C₂₀H₂₀NOP
M_r	321.34
Crystal system, space group	Orthorhombic, Pca2₁
Temperature (K)	100
a, b, c (Å)	15.9713 (9), 10.7495 (7), 9.8286 (6)
V (Å³)	1687.41 (18)
Z	4
Radiation type	Mo Kα
μ (mm⁻¹)	0.17
Crystal size (mm)	0.36 × 0.28 × 0.11

Data collection
Diffractometer	Bruker SMART APEX CCD
Absorption correction	Multi-scan (SADABS; Bruker, 2016 )
T_min, T_max	0.829, 0.942
No. of measured, independent and observed [I > 2σ(I)] reflections	25376, 5327, 4160
R_int	0.061
(sin θ/λ)_max (Å⁻¹)	0.725

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.048, 0.108, 1.04
No. of reflections	5327
No. of parameters	210
No. of restraints	1
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.37, −0.38
Absolute structure	Flack x determined using 1497 quotients [(I⁺)−(I⁻)]/[(I⁺)+(I⁻)] (Parsons et al., 2013 )
Absolute structure parameter	0.07 (5)
Computer programs: APEX2 and SAINT (Bruker, 2013 ), SHELXT2014 (Sheldrick, 2015a ), SHELXL2016 (Sheldrick, 2015b ), Mercury (Macrae et al., 2006 ) and SHELXTL (Sheldrick, 2008 ).

Structural data

CCDC reference: 1863429

Crystal structure: contains datablock I. DOI: https://doi.org/10.1107/S2414314618011926/hb4258sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314618011926/hb4258Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S2414314618011926/hb4258Isup3.cml

checkCIF report

Computing details top

Data collection: APEX2 (Bruker, 2013); cell refinement: SAINT (Bruker, 2013); data reduction: SAINT (Bruker, 2013); program(s) used to solve structure: SHELXT2014 (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2016 (Sheldrick, 2015b); molecular graphics: Mercury (Macrae et al., 2006); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

N-(3,5-Dimethylphenyl)-P,P-diphenylphosphinic amide top

Crystal data top

C₂₀H₂₀NOP	D_x = 1.265 Mg m⁻³
M_r = 321.34	Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, Pca2₁	Cell parameters from 5345 reflections
a = 15.9713 (9) Å	θ = 3.1–29.8°
b = 10.7495 (7) Å	µ = 0.17 mm⁻¹
c = 9.8286 (6) Å	T = 100 K
V = 1687.41 (18) Å³	Rectangular, colourless
Z = 4	0.36 × 0.28 × 0.11 mm
F(000) = 680

Data collection top

Bruker SMART APEX CCD diffractometer	5327 independent reflections
Radiation source: sealed tube	4160 reflections with I > 2σ(I)
Detector resolution: 8 pixels mm^-1	R_int = 0.061
ω and φ scans	θ_max = 31.0°, θ_min = 1.9°
Absorption correction: multi-scan (SADABS; Bruker, 2016)	h = −16→23
T_min = 0.829, T_max = 0.942	k = −15→15
25376 measured reflections	l = −14→14

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: mixed
R[F² > 2σ(F²)] = 0.048	H-atom parameters constrained
wR(F²) = 0.108	w = 1/[σ²(F_o²) + (0.0495P)² + 0.1102P] where P = (F_o² + 2F_c²)/3
S = 1.04	(Δ/σ)_max < 0.001
5327 reflections	Δρ_max = 0.37 e Å⁻³
210 parameters	Δρ_min = −0.38 e Å⁻³
1 restraint	Absolute structure: Flack x determined using 1497 quotients [(I⁺)-(I^-)]/[(I⁺)+(I^-)] (Parsons et al., 2013)
Primary atom site location: dual	Absolute structure parameter: 0.07 (5)

Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Refinement. All H atoms were positioned geometrically and refined using a riding model with C—H = 0.95–0.99 Å and with U_iso(H) = 1.2 (1.5 for methyl groups) times U_eq(C).

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

	x	y	z	U_iso*/U_eq
P1	0.69664 (4)	0.49044 (6)	0.38310 (8)	0.01446 (14)
O1	0.70603 (12)	0.5330 (2)	0.2410 (2)	0.0234 (5)
N1	0.71536 (13)	0.5990 (2)	0.4983 (2)	0.0162 (5)
H1	0.709159	0.565487	0.579440	0.019*
C1	0.68182 (15)	0.7201 (2)	0.5019 (3)	0.0154 (5)
C2	0.63941 (14)	0.7720 (2)	0.3912 (3)	0.0171 (5)
H2	0.630838	0.723925	0.311269	0.020*
C3	0.60956 (15)	0.8938 (3)	0.3973 (3)	0.0201 (6)
C4	0.62074 (16)	0.9628 (3)	0.5159 (3)	0.0219 (6)
H4	0.599481	1.045187	0.520752	0.026*
C5	0.66277 (16)	0.9125 (3)	0.6280 (3)	0.0204 (6)
C6	0.69365 (15)	0.7911 (3)	0.6188 (3)	0.0170 (5)
H6	0.723196	0.756459	0.693638	0.020*
C7	0.56648 (18)	0.9491 (3)	0.2749 (3)	0.0276 (7)
H7A	0.601677	0.937469	0.194249	0.041*
H7B	0.557222	1.038154	0.289994	0.041*
H7C	0.512526	0.907574	0.261002	0.041*
C8	0.67299 (19)	0.9845 (3)	0.7585 (3)	0.0267 (7)
H8A	0.667692	1.073669	0.739848	0.040*
H8B	0.728343	0.967449	0.797312	0.040*
H8C	0.629586	0.959041	0.823277	0.040*
C9	0.77031 (15)	0.3712 (2)	0.4290 (3)	0.0162 (5)
C10	0.85145 (16)	0.3818 (3)	0.3759 (4)	0.0230 (6)
H10	0.864781	0.448842	0.316708	0.028*
C11	0.91222 (16)	0.2954 (3)	0.4091 (3)	0.0259 (7)
H11	0.967111	0.303452	0.372958	0.031*
C12	0.89351 (17)	0.1976 (3)	0.4945 (3)	0.0231 (6)
H12	0.935353	0.138266	0.517217	0.028*
C13	0.81298 (18)	0.1860 (3)	0.5474 (3)	0.0273 (7)
H13	0.799857	0.118741	0.606324	0.033*
C14	0.75191 (18)	0.2725 (3)	0.5141 (3)	0.0234 (6)
H14	0.697004	0.263892	0.550083	0.028*
C15	0.59332 (15)	0.4278 (2)	0.4110 (3)	0.0162 (5)
C16	0.54908 (17)	0.4479 (3)	0.5302 (3)	0.0221 (6)
H16	0.572231	0.498776	0.599668	0.026*
C17	0.47006 (18)	0.3932 (3)	0.5484 (4)	0.0313 (7)
H17	0.439077	0.408013	0.629256	0.038*
C18	0.43792 (18)	0.3179 (3)	0.4481 (4)	0.0334 (8)
H18	0.385194	0.278845	0.461449	0.040*
C19	0.48081 (19)	0.2982 (3)	0.3290 (4)	0.0300 (7)
H19	0.457270	0.247131	0.260043	0.036*
C20	0.55888 (17)	0.3533 (3)	0.3091 (3)	0.0236 (6)
H20	0.588524	0.340067	0.226604	0.028*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
P1	0.0130 (2)	0.0162 (3)	0.0142 (3)	−0.0003 (3)	0.0002 (3)	−0.0005 (3)
O1	0.0247 (10)	0.0268 (11)	0.0188 (10)	−0.0004 (9)	0.0030 (8)	0.0033 (9)
N1	0.0179 (10)	0.0146 (11)	0.0159 (11)	0.0010 (9)	−0.0010 (9)	−0.0010 (9)
C1	0.0107 (10)	0.0155 (13)	0.0200 (13)	−0.0019 (10)	0.0017 (10)	0.0025 (11)
C2	0.0134 (10)	0.0191 (12)	0.0187 (12)	−0.0023 (9)	0.0009 (11)	−0.0014 (12)
C3	0.0118 (10)	0.0211 (13)	0.0274 (15)	−0.0015 (10)	0.0026 (11)	0.0083 (12)
C4	0.0133 (11)	0.0161 (13)	0.0363 (17)	0.0004 (10)	0.0060 (12)	0.0008 (12)
C5	0.0135 (12)	0.0194 (14)	0.0283 (15)	−0.0023 (11)	0.0063 (11)	−0.0044 (12)
C6	0.0130 (11)	0.0187 (14)	0.0194 (13)	−0.0005 (10)	0.0010 (10)	−0.0025 (11)
C7	0.0234 (14)	0.0248 (16)	0.0346 (18)	0.0019 (13)	−0.0025 (13)	0.0111 (14)
C8	0.0235 (14)	0.0218 (16)	0.0349 (17)	0.0004 (12)	0.0031 (13)	−0.0110 (14)
C9	0.0133 (11)	0.0161 (13)	0.0192 (13)	−0.0010 (10)	−0.0005 (10)	−0.0052 (11)
C10	0.0190 (11)	0.0216 (13)	0.0285 (14)	−0.0002 (11)	0.0067 (13)	−0.0015 (14)
C11	0.0145 (11)	0.0259 (15)	0.0374 (19)	0.0016 (11)	0.0037 (12)	−0.0072 (14)
C12	0.0199 (13)	0.0233 (15)	0.0260 (15)	0.0070 (12)	−0.0054 (12)	−0.0077 (13)
C13	0.0258 (15)	0.0233 (15)	0.0328 (17)	0.0039 (13)	0.0029 (13)	0.0084 (13)
C14	0.0151 (11)	0.0228 (14)	0.0322 (16)	0.0009 (12)	0.0047 (11)	0.0046 (13)
C15	0.0134 (10)	0.0177 (13)	0.0176 (14)	0.0022 (10)	−0.0019 (9)	0.0004 (10)
C16	0.0206 (13)	0.0248 (15)	0.0209 (14)	0.0001 (12)	0.0035 (11)	0.0010 (12)
C17	0.0227 (14)	0.0325 (18)	0.0387 (19)	0.0000 (14)	0.0128 (14)	0.0061 (15)
C18	0.0132 (13)	0.0242 (16)	0.063 (2)	−0.0020 (12)	0.0027 (14)	0.0056 (17)
C19	0.0181 (13)	0.0279 (18)	0.0439 (19)	−0.0021 (13)	−0.0095 (13)	−0.0053 (15)
C20	0.0204 (13)	0.0248 (16)	0.0256 (14)	−0.0023 (12)	−0.0022 (12)	−0.0057 (12)

Geometric parameters (Å, º) top

P1—O1	1.477 (2)	C9—C14	1.383 (4)
P1—N1	1.653 (2)	C9—C10	1.402 (4)
P1—C9	1.797 (3)	C10—C11	1.383 (4)
P1—C15	1.803 (3)	C10—H10	0.9500
N1—C1	1.409 (3)	C11—C12	1.378 (4)
N1—H1	0.8805	C11—H11	0.9500
C1—C6	1.393 (4)	C12—C13	1.393 (4)
C1—C2	1.397 (4)	C12—H12	0.9500
C2—C3	1.395 (4)	C13—C14	1.387 (4)
C2—H2	0.9500	C13—H13	0.9500
C3—C4	1.393 (4)	C14—H14	0.9500
C3—C7	1.507 (4)	C15—C16	1.385 (4)
C4—C5	1.398 (4)	C15—C20	1.395 (4)
C4—H4	0.9500	C16—C17	1.404 (4)
C5—C6	1.398 (4)	C16—H16	0.9500
C5—C8	1.507 (4)	C17—C18	1.374 (5)
C6—H6	0.9500	C17—H17	0.9500
C7—H7A	0.9800	C18—C19	1.373 (5)
C7—H7B	0.9800	C18—H18	0.9500
C7—H7C	0.9800	C19—C20	1.394 (4)
C8—H8A	0.9800	C19—H19	0.9500
C8—H8B	0.9800	C20—H20	0.9500
C8—H8C	0.9800

O1—P1—N1	114.24 (13)	H8B—C8—H8C	109.5
O1—P1—C9	113.07 (12)	C14—C9—C10	119.0 (2)
N1—P1—C9	102.29 (12)	C14—C9—P1	124.1 (2)
O1—P1—C15	110.62 (12)	C10—C9—P1	117.0 (2)
N1—P1—C15	108.97 (12)	C11—C10—C9	120.4 (3)
C9—P1—C15	107.14 (12)	C11—C10—H10	119.8
C1—N1—P1	126.92 (19)	C9—C10—H10	119.8
C1—N1—H1	108.2	C12—C11—C10	120.3 (3)
P1—N1—H1	108.1	C12—C11—H11	119.9
C6—C1—C2	119.3 (2)	C10—C11—H11	119.9
C6—C1—N1	118.4 (2)	C11—C12—C13	119.7 (3)
C2—C1—N1	122.3 (2)	C11—C12—H12	120.2
C3—C2—C1	120.4 (3)	C13—C12—H12	120.2
C3—C2—H2	119.8	C14—C13—C12	120.1 (3)
C1—C2—H2	119.8	C14—C13—H13	119.9
C4—C3—C2	119.4 (3)	C12—C13—H13	119.9
C4—C3—C7	121.1 (3)	C9—C14—C13	120.5 (3)
C2—C3—C7	119.5 (3)	C9—C14—H14	119.7
C3—C4—C5	121.0 (3)	C13—C14—H14	119.7
C3—C4—H4	119.5	C16—C15—C20	119.7 (2)
C5—C4—H4	119.5	C16—C15—P1	122.5 (2)
C6—C5—C4	118.6 (3)	C20—C15—P1	117.8 (2)
C6—C5—C8	119.7 (3)	C15—C16—C17	120.1 (3)
C4—C5—C8	121.6 (3)	C15—C16—H16	120.0
C1—C6—C5	121.1 (3)	C17—C16—H16	120.0
C1—C6—H6	119.4	C18—C17—C16	119.4 (3)
C5—C6—H6	119.4	C18—C17—H17	120.3
C3—C7—H7A	109.5	C16—C17—H17	120.3
C3—C7—H7B	109.5	C19—C18—C17	121.0 (3)
H7A—C7—H7B	109.5	C19—C18—H18	119.5
C3—C7—H7C	109.5	C17—C18—H18	119.5
H7A—C7—H7C	109.5	C18—C19—C20	120.0 (3)
H7B—C7—H7C	109.5	C18—C19—H19	120.0
C5—C8—H8A	109.5	C20—C19—H19	120.0
C5—C8—H8B	109.5	C19—C20—C15	119.7 (3)
H8A—C8—H8B	109.5	C19—C20—H20	120.1
C5—C8—H8C	109.5	C15—C20—H20	120.1
H8A—C8—H8C	109.5

O1—P1—N1—C1	49.7 (2)	C14—C9—C10—C11	−0.5 (4)
C9—P1—N1—C1	172.3 (2)	P1—C9—C10—C11	178.5 (2)
C15—P1—N1—C1	−74.5 (2)	C9—C10—C11—C12	0.2 (5)
P1—N1—C1—C6	169.28 (19)	C10—C11—C12—C13	0.0 (5)
P1—N1—C1—C2	−12.5 (4)	C11—C12—C13—C14	0.1 (5)
C6—C1—C2—C3	0.4 (4)	C10—C9—C14—C13	0.6 (4)
N1—C1—C2—C3	−177.9 (2)	P1—C9—C14—C13	−178.4 (2)
C1—C2—C3—C4	−1.4 (4)	C12—C13—C14—C9	−0.4 (5)
C1—C2—C3—C7	178.0 (2)	O1—P1—C15—C16	−141.0 (2)
C2—C3—C4—C5	1.2 (4)	N1—P1—C15—C16	−14.7 (3)
C7—C3—C4—C5	−178.2 (2)	C9—P1—C15—C16	95.3 (2)
C3—C4—C5—C6	0.0 (4)	O1—P1—C15—C20	41.0 (3)
C3—C4—C5—C8	−178.1 (2)	N1—P1—C15—C20	167.4 (2)
C2—C1—C6—C5	0.9 (4)	C9—P1—C15—C20	−82.6 (2)
N1—C1—C6—C5	179.2 (2)	C20—C15—C16—C17	0.2 (4)
C4—C5—C6—C1	−1.1 (4)	P1—C15—C16—C17	−177.7 (2)
C8—C5—C6—C1	177.0 (2)	C15—C16—C17—C18	1.2 (5)
O1—P1—C9—C14	−143.4 (2)	C16—C17—C18—C19	−1.8 (5)
N1—P1—C9—C14	93.3 (3)	C17—C18—C19—C20	1.1 (5)
C15—P1—C9—C14	−21.2 (3)	C18—C19—C20—C15	0.3 (5)
O1—P1—C9—C10	37.7 (3)	C16—C15—C20—C19	−0.9 (4)
N1—P1—C9—C10	−85.7 (2)	P1—C15—C20—C19	177.1 (2)
C15—P1—C9—C10	159.8 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2···O1	0.95	2.48	3.148 (3)	128
N1—H1···O1ⁱ	0.88	2.12	2.788 (3)	133

Symmetry code: (i) −x+3/2, y, z+1/2.

Acknowledgements

The authors thank Mr Trevahn M. Williams for his assistance in preparing some of the starting materials for this work.

Funding information

Funding for this research was provided by: National Science Foundation, Division of Chemistry (award No. MRI, CHE-0420497 to UMSL); College of Arts and Sciences, Southern Illinois University Edwardsville; Graduate School, Southern Illinois University Edwardsville.

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