organic compounds
N-(3,5-Dimethylphenyl)-P,P-diphenylphosphinic amide
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
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.
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 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 .
details are summarized in Table 2Structural data
CCDC reference: 1863429
https://doi.org/10.1107/S2414314618011926/hb4258sup1.cif
contains datablock I. DOI: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
Data collection: APEX2 (Bruker, 2013); cell
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).C20H20NOP | Dx = 1.265 Mg m−3 |
Mr = 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 |
Bruker SMART APEX CCD diffractometer | 5327 independent reflections |
Radiation source: sealed tube | 4160 reflections with I > 2σ(I) |
Detector resolution: 8 pixels mm-1 | Rint = 0.061 |
ω and φ scans | θmax = 31.0°, θmin = 1.9° |
Absorption correction: multi-scan (SADABS; Bruker, 2016) | h = −16→23 |
Tmin = 0.829, Tmax = 0.942 | k = −15→15 |
25376 measured reflections | l = −14→14 |
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(Fo2) + (0.0495P)2 + 0.1102P] where P = (Fo2 + 2Fc2)/3 |
S = 1.04 | (Δ/σ)max < 0.001 |
5327 reflections | Δρmax = 0.37 e Å−3 |
210 parameters | Δρmin = −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) |
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 Uiso(H) = 1.2 (1.5 for methyl groups) times Ueq(C). |
x | y | z | Uiso*/Ueq | ||
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* |
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) |
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) |
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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