research communications
Crystal structures of two bis-carbamoylmethylphosphine oxide (CMPO) compounds
aDepartment of Chemistry, Grand Valley State University, 1 Campus Dr., Allendale, MI 49401, USA, and bCenter for Crystallographic Research, Department of Chemistry, Michigan State University, East Lansing, MI 48824, USA
*Correspondence e-mail: biross@gvsu.edu
Two bis-carbamoylmethylphosphine oxide compounds, namely {[(3-{[2-(diphenylphosphinoyl)ethanamido]methyl}benzyl)carbamoyl]methyl}diphenylphosphine oxide, C36H34N2O4P2, (I), and diethyl [({2-[2-(diethoxyphosphinoyl)ethanamido]ethyl}carbamoyl)methyl]phosphonate, C14H30N2O8P2, (II), were synthesized via nucleophilic acyl substitution reactions between an ester and a primary amine. Hydrogen-bonding interactions are present in both crystals, but these interactions are intramolecular in the case of compound (I) and intermolecular in compound (II). Intramolecular π–π stacking interactions are also present in the crystal of compound (I) with a centroid–centroid distance of 3.9479 (12) Å and a dihedral angle of 9.56 (12)°. Intermolecular C—H⋯π interactions [C⋯centroid distance of 3.622 (2) Å, C—H⋯centroid angle of 146°] give rise to supramolecular sheets that lie in the ab plane. Key geometric features for compound (I) involve a nearly planar, trans-amide group with a C—N—C—C torsion angle of 169.12 (17)°, and a torsion angle of −108.39 (15)° between the phosphine oxide phosphorus atom and the amide nitrogen atom. For compound (II), the electron density corresponding to the phosphoryl group was disordered, and was modeled as two parts with a 0.7387 (19):0.2613 (19) occupancy ratio. Compound (II) also boasts a trans-amide group that approaches planarity with a C—N—C—C torsion angle of −176.50 (16)°. The hydrogen bonds in this structure are intermolecular, with a D⋯A distance of 2.883 (2) Å and a D—H⋯A angle of 175.0 (18)° between the amide hydrogen atom and the P=O oxygen atom. These non-covalent interactions create ribbons that run along the b-axis direction.
1. Chemical context
The carbamoylmethylphosphine oxide (CMPO) moiety has found use as the chelating portion of a ligand in the TRUEX process for the remediation of nuclear waste (Horwitz et al., 1985). It has been shown that the CMPO group binds lanthanide (Ln) and actinide (An) metals in a 1:2 or 1:3 metal-ligand ratio in solution, depending on the size of the metal ion. Many researchers have attempted to mimic this solution stoichiometry by tethering two, three or four CMPO groups together via an organic scaffold (Dam et al., 2007; Leoncini et al., 2017; Miyazaki et al., 2015; Sharova et al., 2014; Werner & Biros, 2019). In some cases, these multidentate ligands have demonstrated an increased binding affinity for certain Ln and An ions, as well as an increased ability to extract these metals out of aqueous solutions. To this end, we report here the synthesis of compounds (I) and (II) and their characterization by 1H, 13C, and 31P NMR spectroscopy, and by X-ray crystallography.
2. Structural commentary
The structure of compound (I) was solved in the monoclinic C2/c. Since the entire molecule straddles a twofold symmetry axis, the is composed of one half of the compound. The complete molecular structure of compound (I) is shown in Fig. 1 along with the atom-labeling scheme. The P=O bond length is 1.4915 (13) Å, with P—C bond lengths that range from 1.7988 (18) to 1.8169 (19) Å. The τ4 descriptor for fourfold coordination around the phosphorus atom P1 is 0.95, indicating a nearly perfect tetrahedral geometry of the phosphine oxide group (where 0.00 = square-planar, 0.85 = trigonal–pyramidal, and 1.00 = tetrahedral; Yang et al., 2007). The geometry between the amide nitrogen atom N1 and the β-phosphine oxide phosphorus atom P1 is defined by a P1—C2—C1—N1 torsion angle of −108.39 (15)°. The amide group adopts a nearly perfect trans geometry with a C3—N1—C1—C2 torsion angle of 169.12 (17)°, and is staggered with respect to the plane of the C4–C7 aromatic ring with a H1—N1—C3—C4 torsion angle of 59.1 (17)°.
Intramolecular non-covalent interactions are also present in the crystal of compound (I). Hydrogen bonds between the amide hydrogen H1 and the phosphine oxide oxygen atom O2(−x + 1, y, −z + ) have a D⋯A distance of 2.940 (2) Å and a D—H⋯A angle of 168 (2)° (Fig. 3 and Table 1). The C14–C19 aromatic ring of this compound is engaged in an intramolecular π–π stacking interaction with its symmetry-derived counterpart with an intercentroid distance of 3.9479 (12) Å, slippage of 1.521 (1) Å and a dihedral angle of 9.56 (12)°.
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Compound (II) crystallizes in the orthorhombic Pbca. Since the molecule lies on an inversion center (at 2 − x, 1 − y, 1 − z), the comprises one half of the molecule. The electron density corresponding to the atoms of the phosphoryl group was disordered and was modeled over two positions with a 0.7387 (19):0.2613 (19) occupancy ratio (see the Refinement section for more details). The complete molecular structure of the major component of compound (II) is shown in Fig. 2 along with the labeling scheme. For the major component, the P=O bond length is 1.474 (2) Å, with P—O bond lengths of 1.5791 (16) and 1.5619 (15) Å, and a P—C bond length of 1.801 (2) Å. The τ4 descriptor for fourfold coordination around the phosphorus atom of the major component, P1, is 0.93, indicating that the geometry of the phosphoryl group is slightly distorted from an ideal tetrahedron. The geometry between the amide nitrogen atom N1 and the β-phosphoryl group phosphorus atom P1 is defined by a N1—C1—C2—P1 torsion angle of −111.8 (2)°. The amide group of this compound also adopts a nearly perfect trans geometry with a C3—N1—C1—C2 torsion angle of −176.50 (16)°.
3. Supramolecular features
The C14–C19 aromatic ring of compound (I) hosts a C—H⋯π interaction with H3A (symmetry code: − + x, + y, z) with a C⋯centroid distance of 3.622 (2) Å and a C—H⋯centroid angle of 146°. These non-covalent interactions create supramolecular sheets of compound (I) that lie in the ab plane (Fig. 4).
The displays intermolecular hydrogen bonds between the amide hydrogen H1 and the oxygen atom O2 of the phosphoryl group of a neighboring molecule (symmetry code: x + , −y + , −z + 1; Fig. 5 and Table 2). This hydrogen bond is present for both parts of the disordered phosphoryl group. For the major component, this hydrogen bond has a D⋯A distance of 2.883 (2) Å with a D—H⋯A angle of 175.0 (18)°. This hydrogen bond forms ribbons of compound (I) that run along the b-axis direction (Fig. 6).
of compound (II)4. Database survey
The Cambridge Structural Database (CSD, Version 5.40, November 2018; Groom et al., 2016) contains 19 structures which have a CMPO group as part of an organic compound. (This count excludes metal complexes.) Of these, seven structures have two or more CMPO groups tethered to one another via an organic scaffold. The most similar structures to compound (I) are CIWFAR (Ouizem et al., 2014) and SISLIQ (Artyushin et al., 2006). Both structures use an aromatic ring as the scaffold to present two phenyl-substituted CMPO groups. In SISLIQ, a 1,2-disubstituted benzene ring is utilized to present the CMPO groups. In CIWFAR, the scaffold is a pyridine ring where the 2- and 6-positions bear CMPO groups, which makes it directly analogous to compound (I). The amide hydrogens of CIWFAR are engaged in intermolecular hydrogen bonds with the oxygen atoms of the phosphine oxide groups [rather than the intramolecular interaction observed for compound (I)], and the pyridine nitrogen is hydrogen bonded to the –OH group of a solvent methanol molecule. The hydrogen atoms of the pyridine scaffold interact with the phenyl rings of the phosphine oxide via intermolecular C—H⋯π interactions. A structure closely related to compound (II) was reported by the Rebek group as OGIVIJ (Amrhein, et al., 2002). Here, a resorcin[4]arene scaffold presents two ethoxy-substituted CMPO units. We also note that the structure of compound (II) complexed with Sm(NO3)3 has been reported in this journal (Stoscup et al., 2014).
5. Synthesis and crystallization
Compound (I): 1,3-Bis(aminomethyl)benzene (128 mg, 0.124 mL, 0.785 mmol) and the p-nitrophenyl ester of diphenylphosphonoacetate (Arnaud-Neu et al., 1996) (1.0 g, 3.14 mmol) were dissolved in anhydrous, ethanol-free chloroform (30 mL). The solution was heated to 313 K and stirred for three days. The reaction mixture was then allowed to cool to room temperature, a small amount of 40% KOH was added (ca. 3 mL) and the solution was stirred for 3.5 h. The organic layer was separated, washed with brine (3 × 10 mL), dried over solid magnesium sulfate and concentrated under reduced pressure. The crude product was triturated multiple times with ethyl acetate to give a white solid in 91% yield. X-ray quality crystals of compound (I) were grown by slow evaporation of a chloroform solution. 1H NMR (400 MHz, CDCl3): δ 7.91 (t, J = 5.3 Hz, 2H, –NH), 7.7–7.3 (m, 20H), 7.1–6.8 (m, 4H), 4.24 (d, J = 7.2 Hz, 4H), 3.36 (d, JP–H = 13.2 Hz, 4H); 13C NMR (100 MHz, CDCl3): δ 164.7 (d, JP–C = 4.5 Hz), 138.3, 132.5, 131.9, 131.2–130.5 (broad), 129.5–128.3 (broad), 126.9–126.1 (broad), 43.5, 38.6; 31P NMR (161 MHz, CDCl3): δ 30.6.
Compound (II): Ethylene diamine (1.0 mL, 14.9 mmol) was dissolved in 8.3 mL of methanol. The solution was cooled to 195 K, and triethyl phosphonoacetate (8.8 mL, 44.8 mmol) was added dropwise. The reaction mixture was allowed to warm to room temperature and stirred overnight. The product precipitated from the solution, was isolated by vacuum filtration and rinsed with ethyl acetate. Some of this solid was crystalline and suitable for analysis by X-ray diffraction. The remainder of the isolated product was purified by silica gel (10:1 dichloromethane–methanol) to give compound (II) as a white solid (37% yield). 1H NMR (300 MHz, CDCl3): δ 7.75 (broad, 2H, –NH), 4.15 (q, J = 7.0 Hz, 8H), 3.34 (d, J = 5.9 Hz, 8H), 2.85 (q, JP–H = 15.8 Hz, 8H), 1.33 (t, J = 7.0 Hz, 12H); 13C NMR (75 MHz, CDCl3): δ 165.4, 62.9, 35.8 (d, JP–C = 128 Hz), 16.5; 31P NMR (121 MHz, CDCl3): δ 24.5.
6. Refinement
Crystal data, data collection and structure . For compounds (I) and (II), all hydrogen atoms bonded to carbon atoms were placed in calculated positions and refined as riding: C—H = 0.95–1.00 Å with Uiso(H) = 1.2Ueq(C) for methylene groups and aromatic hydrogen atoms, and Uiso(H) = 1.5Ueq(C) for methyl groups. For both compounds (I) and (II), the hydrogen atoms bonded to nitrogen atoms were located using electron-density difference maps. The disordered electron density corresponding to the phosphoryl group of compound (II) was modeled over two positions with a relative occupancy ratio of 0.7387 (19):0.2613 (19). The C5—C4 and C6—C7 bond lengths were restrained using DFIX instructions in SHELXL (Sheldrick, 2015) at 1.5 Å to agree with known values. Atoms of each part (P1, P1A, O2–O4, O2A–O4A, C2, C2A, C5–C7, C5A–C7A) were treated with SAME and EADP commands to produce bond lengths and angles that agree with known values, and to ensure physically reasonable displacement parameters.
details for both compounds are summarized in Table 3Supporting information
https://doi.org/10.1107/S205698901900820X/pk2617sup1.cif
contains datablocks I, II. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S205698901900820X/pk2617Isup2.hkl
Structure factors: contains datablock II. DOI: https://doi.org/10.1107/S205698901900820X/pk2617IIsup3.hkl
Supporting information file. DOI: https://doi.org/10.1107/S205698901900820X/pk2617Isup4.cml
Supporting information file. DOI: https://doi.org/10.1107/S205698901900820X/pk2617IIsup5.cml
For both structures, data collection: APEX2 (Bruker, 2013); cell
SAINT (Bruker, 2013); data reduction: SAINT (Bruker, 2013). Program(s) used to solve structure: SHELXS (Sheldrick, 2008) for (I); olex2.solve (Bourhis et al., 2015) for (II). For both structures, program(s) used to refine structure: SHELXL (Sheldrick, 2015). Molecular graphics: OLEX2 (Dolomanov et al., 2009; Bourhis et al., 2015) for (I); OLEX2 (Dolomanov et al., 2009) for (II). Software used to prepare material for publication: CrystalMaker (Palmer, 2007) for (I); OLEX2 (Dolomanov et al., 2009) for (II).C36H34N2O4P2 | F(000) = 1304 |
Mr = 620.59 | Dx = 1.312 Mg m−3 |
Monoclinic, C2/c | Cu Kα radiation, λ = 1.54178 Å |
a = 13.0352 (2) Å | Cell parameters from 7639 reflections |
b = 14.1348 (4) Å | θ = 4.6–71.9° |
c = 17.0471 (4) Å | µ = 1.60 mm−1 |
β = 90.217 (2)° | T = 173 K |
V = 3140.90 (13) Å3 | Needle, colourless |
Z = 4 | 0.38 × 0.11 × 0.08 mm |
Bruker APEXII CCD diffractometer | 2543 reflections with I > 2σ(I) |
φ and ω scans | Rint = 0.050 |
Absorption correction: multi-scan (SADABS; Bruker, 2013) | θmax = 72.1°, θmin = 4.6° |
Tmin = 0.617, Tmax = 0.754 | h = −16→16 |
16825 measured reflections | k = −17→16 |
3022 independent reflections | l = −21→20 |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Hydrogen site location: mixed |
R[F2 > 2σ(F2)] = 0.041 | H atoms treated by a mixture of independent and constrained refinement |
wR(F2) = 0.117 | w = 1/[σ2(Fo2) + (0.071P)2 + 1.6884P] where P = (Fo2 + 2Fc2)/3 |
S = 1.03 | (Δ/σ)max = 0.001 |
3022 reflections | Δρmax = 0.33 e Å−3 |
204 parameters | Δρmin = −0.27 e Å−3 |
0 restraints |
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. |
x | y | z | Uiso*/Ueq | ||
P1 | 0.61558 (3) | 0.01942 (3) | 0.65310 (2) | 0.02456 (15) | |
O1 | 0.51178 (11) | 0.16409 (10) | 0.52941 (8) | 0.0387 (4) | |
O2 | 0.63820 (10) | 0.08953 (9) | 0.71622 (8) | 0.0319 (3) | |
N1 | 0.40562 (13) | 0.18290 (11) | 0.63349 (10) | 0.0304 (4) | |
H1 | 0.3839 (17) | 0.1569 (16) | 0.6753 (14) | 0.031 (6)* | |
C1 | 0.46922 (13) | 0.13271 (13) | 0.58793 (10) | 0.0279 (4) | |
C2 | 0.48641 (14) | 0.03112 (13) | 0.61386 (10) | 0.0279 (4) | |
H2A | 0.477236 | −0.012087 | 0.568671 | 0.033* | |
H2B | 0.435750 | 0.013809 | 0.654532 | 0.033* | |
C3 | 0.39481 (17) | 0.28492 (14) | 0.62513 (12) | 0.0367 (5) | |
H3A | 0.321015 | 0.301452 | 0.625674 | 0.044* | |
H3B | 0.422971 | 0.304441 | 0.573764 | 0.044* | |
C4 | 0.44947 (14) | 0.33936 (13) | 0.68985 (12) | 0.0323 (4) | |
C5 | 0.44880 (15) | 0.43806 (14) | 0.69115 (14) | 0.0388 (5) | |
H5 | 0.413150 | 0.472302 | 0.651594 | 0.047* | |
C6 | 0.500000 | 0.4858 (2) | 0.750000 | 0.0418 (7) | |
H6 | 0.500001 | 0.553010 | 0.750000 | 0.050* | |
C7 | 0.500000 | 0.29186 (19) | 0.750000 | 0.0337 (6) | |
H7 | 0.500000 | 0.224650 | 0.750000 | 0.040* | |
C8 | 0.70406 (14) | 0.03028 (13) | 0.57209 (10) | 0.0282 (4) | |
C9 | 0.75675 (18) | 0.11496 (16) | 0.56285 (13) | 0.0430 (5) | |
H9 | 0.745261 | 0.165338 | 0.598650 | 0.052* | |
C10 | 0.8259 (2) | 0.12686 (19) | 0.50205 (16) | 0.0560 (7) | |
H10 | 0.862193 | 0.184740 | 0.496512 | 0.067* | |
C11 | 0.84148 (19) | 0.0541 (2) | 0.44976 (15) | 0.0575 (7) | |
H11 | 0.888183 | 0.062054 | 0.407633 | 0.069* | |
C12 | 0.78956 (18) | −0.03057 (19) | 0.45821 (14) | 0.0495 (6) | |
H12 | 0.800717 | −0.080434 | 0.421862 | 0.059* | |
C13 | 0.72129 (15) | −0.04301 (15) | 0.51949 (12) | 0.0355 (4) | |
H13 | 0.686365 | −0.101540 | 0.525499 | 0.043* | |
C14 | 0.62569 (14) | −0.10082 (13) | 0.68680 (11) | 0.0278 (4) | |
C15 | 0.57441 (16) | −0.17625 (14) | 0.65110 (12) | 0.0342 (4) | |
H15 | 0.527354 | −0.164934 | 0.609453 | 0.041* | |
C16 | 0.59268 (17) | −0.26772 (15) | 0.67688 (13) | 0.0407 (5) | |
H16 | 0.557730 | −0.319191 | 0.652892 | 0.049* | |
C17 | 0.66130 (17) | −0.28459 (16) | 0.73716 (16) | 0.0472 (6) | |
H17 | 0.674521 | −0.347566 | 0.753841 | 0.057* | |
C18 | 0.71074 (17) | −0.20969 (18) | 0.77322 (15) | 0.0481 (6) | |
H18 | 0.757181 | −0.221448 | 0.815181 | 0.058* | |
C19 | 0.69321 (15) | −0.11785 (15) | 0.74878 (12) | 0.0359 (4) | |
H19 | 0.726984 | −0.066640 | 0.774090 | 0.043* |
U11 | U22 | U33 | U12 | U13 | U23 | |
P1 | 0.0270 (2) | 0.0245 (2) | 0.0222 (2) | 0.00211 (17) | 0.00302 (17) | −0.00095 (16) |
O1 | 0.0434 (8) | 0.0417 (8) | 0.0310 (7) | 0.0046 (6) | 0.0073 (6) | 0.0093 (6) |
O2 | 0.0351 (7) | 0.0325 (7) | 0.0281 (6) | 0.0011 (6) | 0.0016 (5) | −0.0055 (5) |
N1 | 0.0345 (8) | 0.0285 (8) | 0.0283 (8) | 0.0040 (7) | 0.0030 (7) | 0.0035 (6) |
C1 | 0.0282 (9) | 0.0317 (10) | 0.0238 (9) | 0.0006 (7) | −0.0023 (7) | 0.0012 (7) |
C2 | 0.0294 (9) | 0.0291 (9) | 0.0251 (8) | 0.0009 (7) | 0.0022 (7) | −0.0011 (7) |
C3 | 0.0426 (11) | 0.0291 (10) | 0.0385 (11) | 0.0092 (8) | 0.0008 (9) | 0.0063 (8) |
C4 | 0.0296 (9) | 0.0283 (9) | 0.0392 (10) | 0.0032 (7) | 0.0094 (8) | 0.0039 (8) |
C5 | 0.0317 (10) | 0.0297 (10) | 0.0549 (13) | 0.0048 (8) | 0.0128 (9) | 0.0078 (9) |
C6 | 0.0384 (15) | 0.0224 (13) | 0.065 (2) | 0.000 | 0.0157 (14) | 0.000 |
C7 | 0.0376 (14) | 0.0230 (12) | 0.0406 (15) | 0.000 | 0.0051 (12) | 0.000 |
C8 | 0.0262 (8) | 0.0327 (9) | 0.0256 (8) | 0.0033 (7) | 0.0025 (7) | 0.0008 (7) |
C9 | 0.0521 (13) | 0.0356 (11) | 0.0415 (12) | −0.0065 (10) | 0.0124 (10) | −0.0018 (9) |
C10 | 0.0556 (14) | 0.0547 (15) | 0.0577 (15) | −0.0170 (12) | 0.0174 (12) | 0.0078 (12) |
C11 | 0.0456 (13) | 0.0782 (18) | 0.0488 (14) | −0.0083 (13) | 0.0236 (11) | 0.0011 (13) |
C12 | 0.0458 (13) | 0.0615 (15) | 0.0414 (12) | 0.0029 (11) | 0.0146 (10) | −0.0137 (11) |
C13 | 0.0328 (10) | 0.0391 (11) | 0.0346 (10) | −0.0002 (8) | 0.0049 (8) | −0.0050 (8) |
C14 | 0.0293 (9) | 0.0271 (9) | 0.0269 (8) | 0.0046 (7) | 0.0069 (7) | 0.0024 (7) |
C15 | 0.0392 (10) | 0.0327 (10) | 0.0308 (9) | 0.0015 (8) | 0.0041 (8) | 0.0007 (8) |
C16 | 0.0451 (11) | 0.0284 (10) | 0.0487 (12) | −0.0008 (9) | 0.0110 (10) | 0.0017 (9) |
C17 | 0.0375 (11) | 0.0345 (11) | 0.0698 (16) | 0.0057 (9) | 0.0081 (11) | 0.0192 (11) |
C18 | 0.0340 (11) | 0.0506 (13) | 0.0595 (14) | 0.0032 (10) | −0.0052 (10) | 0.0233 (12) |
C19 | 0.0299 (9) | 0.0381 (11) | 0.0398 (11) | −0.0002 (8) | −0.0003 (8) | 0.0062 (9) |
P1—O2 | 1.4915 (13) | C8—C13 | 1.389 (3) |
P1—C2 | 1.8169 (19) | C9—H9 | 0.9500 |
P1—C8 | 1.8091 (18) | C9—C10 | 1.386 (3) |
P1—C14 | 1.7988 (18) | C10—H10 | 0.9500 |
O1—C1 | 1.226 (2) | C10—C11 | 1.377 (4) |
N1—H1 | 0.85 (2) | C11—H11 | 0.9500 |
N1—C1 | 1.341 (2) | C11—C12 | 1.382 (4) |
N1—C3 | 1.456 (2) | C12—H12 | 0.9500 |
C1—C2 | 1.519 (3) | C12—C13 | 1.386 (3) |
C2—H2A | 0.9900 | C13—H13 | 0.9500 |
C2—H2B | 0.9900 | C14—C15 | 1.397 (3) |
C3—H3A | 0.9900 | C14—C19 | 1.393 (3) |
C3—H3B | 0.9900 | C15—H15 | 0.9500 |
C3—C4 | 1.520 (3) | C15—C16 | 1.386 (3) |
C4—C5 | 1.395 (3) | C16—H16 | 0.9500 |
C4—C7 | 1.390 (2) | C16—C17 | 1.381 (3) |
C5—H5 | 0.9500 | C17—H17 | 0.9500 |
C5—C6 | 1.379 (3) | C17—C18 | 1.382 (4) |
C6—H6 | 0.9500 | C18—H18 | 0.9500 |
C7—H7 | 0.9500 | C18—C19 | 1.382 (3) |
C8—C9 | 1.389 (3) | C19—H19 | 0.9500 |
O2—P1—C2 | 112.68 (8) | C9—C8—P1 | 118.45 (15) |
O2—P1—C8 | 111.68 (8) | C13—C8—P1 | 122.32 (15) |
O2—P1—C14 | 112.54 (8) | C13—C8—C9 | 119.22 (18) |
C8—P1—C2 | 107.69 (8) | C8—C9—H9 | 119.6 |
C14—P1—C2 | 105.68 (9) | C10—C9—C8 | 120.8 (2) |
C14—P1—C8 | 106.13 (8) | C10—C9—H9 | 119.6 |
C1—N1—H1 | 117.7 (15) | C9—C10—H10 | 120.3 |
C1—N1—C3 | 121.81 (17) | C11—C10—C9 | 119.4 (2) |
C3—N1—H1 | 118.5 (15) | C11—C10—H10 | 120.3 |
O1—C1—N1 | 124.21 (18) | C10—C11—H11 | 119.8 |
O1—C1—C2 | 120.80 (17) | C10—C11—C12 | 120.4 (2) |
N1—C1—C2 | 114.98 (15) | C12—C11—H11 | 119.8 |
P1—C2—H2A | 109.8 | C11—C12—H12 | 119.9 |
P1—C2—H2B | 109.8 | C11—C12—C13 | 120.3 (2) |
C1—C2—P1 | 109.19 (12) | C13—C12—H12 | 119.9 |
C1—C2—H2A | 109.8 | C8—C13—H13 | 120.1 |
C1—C2—H2B | 109.8 | C12—C13—C8 | 119.9 (2) |
H2A—C2—H2B | 108.3 | C12—C13—H13 | 120.1 |
N1—C3—H3A | 109.1 | C15—C14—P1 | 123.20 (15) |
N1—C3—H3B | 109.1 | C19—C14—P1 | 116.79 (15) |
N1—C3—C4 | 112.67 (16) | C19—C14—C15 | 119.90 (18) |
H3A—C3—H3B | 107.8 | C14—C15—H15 | 120.2 |
C4—C3—H3A | 109.1 | C16—C15—C14 | 119.5 (2) |
C4—C3—H3B | 109.1 | C16—C15—H15 | 120.2 |
C5—C4—C3 | 120.98 (19) | C15—C16—H16 | 119.8 |
C7—C4—C3 | 120.69 (18) | C17—C16—C15 | 120.5 (2) |
C7—C4—C5 | 118.3 (2) | C17—C16—H16 | 119.8 |
C4—C5—H5 | 120.1 | C16—C17—H17 | 120.1 |
C6—C5—C4 | 119.8 (2) | C16—C17—C18 | 119.9 (2) |
C6—C5—H5 | 120.1 | C18—C17—H17 | 120.1 |
C5—C6—C5i | 121.4 (3) | C17—C18—H18 | 119.7 |
C5i—C6—H6 | 119.3 | C19—C18—C17 | 120.6 (2) |
C5—C6—H6 | 119.3 | C19—C18—H18 | 119.7 |
C4—C7—C4i | 122.2 (3) | C14—C19—H19 | 120.2 |
C4—C7—H7 | 118.9 | C18—C19—C14 | 119.6 (2) |
C4i—C7—H7 | 118.9 | C18—C19—H19 | 120.2 |
Symmetry code: (i) −x+1, y, −z+3/2. |
Cg is the centroid of the C14–C19 ring. |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1···O2i | 0.85 (2) | 2.10 (2) | 2.940 (2) | 168 (2) |
C3—H3A···Cgii | 0.99 | 2.76 | 3.622 (2) | 146 |
Symmetry codes: (i) −x+1, y, −z+3/2; (ii) x−1/2, y+1/2, z. |
C14H30N2O8P2 | Dx = 1.306 Mg m−3 |
Mr = 416.34 | Cu Kα radiation, λ = 1.54178 Å |
Orthorhombic, Pbca | Cell parameters from 6034 reflections |
a = 8.9401 (1) Å | θ = 4.1–72.0° |
b = 15.0535 (2) Å | µ = 2.23 mm−1 |
c = 15.7314 (3) Å | T = 173 K |
V = 2117.13 (5) Å3 | Plate, colourless |
Z = 4 | 0.34 × 0.23 × 0.06 mm |
F(000) = 888 |
Bruker APEXII CCD diffractometer | 1839 reflections with I > 2σ(I) |
φ and ω scans | Rint = 0.028 |
Absorption correction: multi-scan (SADABS; Bruker, 2013) | θmax = 72.2°, θmin = 5.6° |
Tmin = 0.612, Tmax = 0.754 | h = −11→10 |
10282 measured reflections | k = −18→12 |
2057 independent reflections | l = −19→16 |
Refinement on F2 | Primary atom site location: iterative |
Least-squares matrix: full | Hydrogen site location: mixed |
R[F2 > 2σ(F2)] = 0.035 | H atoms treated by a mixture of independent and constrained refinement |
wR(F2) = 0.093 | w = 1/[σ2(Fo2) + (0.045P)2 + 0.8277P] where P = (Fo2 + 2Fc2)/3 |
S = 1.05 | (Δ/σ)max < 0.001 |
2057 reflections | Δρmax = 0.21 e Å−3 |
154 parameters | Δρmin = −0.27 e Å−3 |
20 restraints |
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. |
x | y | z | Uiso*/Ueq | Occ. (<1) | |
P1 | 0.49865 (8) | 0.16848 (6) | 0.58724 (5) | 0.0291 (2) | 0.7387 (19) |
O2 | 0.3858 (2) | 0.23508 (12) | 0.56270 (16) | 0.0402 (5) | 0.7387 (19) |
O3 | 0.6214 (2) | 0.20596 (15) | 0.64985 (15) | 0.0364 (4) | 0.7387 (19) |
O4 | 0.43649 (17) | 0.08482 (10) | 0.63416 (10) | 0.0361 (4) | 0.7387 (19) |
C2 | 0.5970 (5) | 0.1213 (3) | 0.49806 (18) | 0.0255 (6) | 0.7387 (19) |
H2A | 0.526044 | 0.087298 | 0.462353 | 0.031* | 0.7387 (19) |
H2B | 0.639568 | 0.169666 | 0.462907 | 0.031* | 0.7387 (19) |
C4 | 0.6892 (3) | 0.2924 (2) | 0.6313 (3) | 0.0433 (7) | 0.7387 (19) |
H4A | 0.620650 | 0.340728 | 0.648672 | 0.052* | 0.7387 (19) |
H4B | 0.708400 | 0.297943 | 0.569581 | 0.052* | 0.7387 (19) |
C5 | 0.8336 (4) | 0.2991 (3) | 0.6797 (3) | 0.0521 (8) | 0.7387 (19) |
H5A | 0.901244 | 0.251520 | 0.661636 | 0.078* | 0.7387 (19) |
H5B | 0.813603 | 0.293490 | 0.740726 | 0.078* | 0.7387 (19) |
H5C | 0.880239 | 0.356862 | 0.668357 | 0.078* | 0.7387 (19) |
C6 | 0.3339 (3) | 0.09235 (16) | 0.70583 (18) | 0.0470 (6) | 0.7387 (19) |
H6A | 0.250321 | 0.132632 | 0.691026 | 0.056* | 0.7387 (19) |
H6B | 0.386886 | 0.117380 | 0.755628 | 0.056* | 0.7387 (19) |
C7 | 0.2754 (9) | 0.0033 (4) | 0.7266 (5) | 0.0514 (10) | 0.7387 (19) |
H7A | 0.209468 | −0.016933 | 0.680694 | 0.077* | 0.7387 (19) |
H7B | 0.218830 | 0.006108 | 0.779863 | 0.077* | 0.7387 (19) |
H7C | 0.358860 | −0.038321 | 0.732867 | 0.077* | 0.7387 (19) |
O1 | 0.69589 (11) | −0.01159 (7) | 0.56001 (7) | 0.0369 (3) | |
N1 | 0.85841 (14) | 0.09068 (9) | 0.51170 (9) | 0.0333 (3) | |
C1 | 0.72039 (15) | 0.06112 (9) | 0.52745 (9) | 0.0287 (3) | |
C3 | 0.98811 (16) | 0.03699 (10) | 0.53232 (10) | 0.0348 (3) | |
H3A | 0.974766 | 0.010625 | 0.589473 | 0.042* | |
H3B | 1.078035 | 0.075326 | 0.533945 | 0.042* | |
P1A | 0.5246 (3) | 0.19107 (16) | 0.60724 (17) | 0.0291 (2) | 0.2613 (19) |
O2A | 0.4150 (8) | 0.2586 (4) | 0.5806 (5) | 0.0402 (5) | 0.2613 (19) |
O3A | 0.6639 (8) | 0.2236 (5) | 0.6594 (5) | 0.0364 (4) | 0.2613 (19) |
O4A | 0.4656 (5) | 0.1195 (3) | 0.6726 (3) | 0.0361 (4) | 0.2613 (19) |
C2A | 0.5883 (17) | 0.1303 (10) | 0.5188 (7) | 0.0255 (6) | 0.2613 (19) |
H2AA | 0.501156 | 0.097716 | 0.495619 | 0.031* | 0.2613 (19) |
H2AB | 0.618606 | 0.173979 | 0.474973 | 0.031* | 0.2613 (19) |
C4A | 0.7429 (11) | 0.3020 (7) | 0.6334 (9) | 0.0433 (7) | 0.2613 (19) |
H4AA | 0.678295 | 0.354818 | 0.640873 | 0.052* | 0.2613 (19) |
H4AB | 0.770059 | 0.297421 | 0.572537 | 0.052* | 0.2613 (19) |
C5A | 0.8806 (14) | 0.3114 (11) | 0.6859 (11) | 0.0521 (8) | 0.2613 (19) |
H5AA | 0.953206 | 0.265798 | 0.669311 | 0.078* | 0.2613 (19) |
H5AB | 0.855187 | 0.304251 | 0.746069 | 0.078* | 0.2613 (19) |
H5AC | 0.924122 | 0.370407 | 0.676741 | 0.078* | 0.2613 (19) |
C6A | 0.3201 (9) | 0.0845 (5) | 0.6622 (5) | 0.0470 (6) | 0.2613 (19) |
H6AA | 0.303480 | 0.070051 | 0.601507 | 0.056* | 0.2613 (19) |
H6AB | 0.245523 | 0.129747 | 0.679118 | 0.056* | 0.2613 (19) |
C7A | 0.299 (3) | 0.0026 (12) | 0.7147 (16) | 0.0514 (10) | 0.2613 (19) |
H7AA | 0.272633 | −0.047288 | 0.677574 | 0.077* | 0.2613 (19) |
H7AB | 0.218138 | 0.012506 | 0.755778 | 0.077* | 0.2613 (19) |
H7AC | 0.391725 | −0.010925 | 0.745083 | 0.077* | 0.2613 (19) |
H1 | 0.871 (2) | 0.1397 (13) | 0.4883 (11) | 0.038 (5)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
P1 | 0.0313 (3) | 0.0177 (4) | 0.0384 (4) | 0.0034 (3) | 0.0024 (3) | 0.0043 (3) |
O2 | 0.0366 (11) | 0.0231 (11) | 0.0610 (14) | 0.0061 (8) | 0.0015 (8) | 0.0068 (9) |
O3 | 0.0456 (14) | 0.0265 (12) | 0.0372 (9) | 0.0008 (8) | −0.0094 (9) | 0.0011 (7) |
O4 | 0.0430 (8) | 0.0243 (8) | 0.0409 (9) | 0.0049 (6) | 0.0152 (7) | 0.0033 (6) |
C2 | 0.0263 (9) | 0.0256 (12) | 0.0248 (18) | 0.0006 (8) | 0.0027 (13) | 0.0054 (13) |
C4 | 0.052 (2) | 0.0284 (12) | 0.0494 (10) | 0.0007 (15) | −0.0097 (18) | 0.0029 (9) |
C5 | 0.053 (3) | 0.0453 (18) | 0.0576 (14) | −0.0050 (17) | −0.012 (2) | 0.0038 (12) |
C6 | 0.0605 (13) | 0.0392 (11) | 0.0413 (14) | −0.0010 (10) | 0.0244 (14) | −0.0052 (12) |
C7 | 0.054 (3) | 0.0554 (12) | 0.045 (2) | −0.0040 (14) | 0.0188 (16) | 0.0094 (12) |
O1 | 0.0330 (5) | 0.0251 (5) | 0.0526 (6) | −0.0028 (4) | −0.0023 (5) | 0.0110 (5) |
N1 | 0.0263 (6) | 0.0241 (6) | 0.0496 (8) | −0.0009 (5) | 0.0012 (5) | 0.0071 (6) |
C1 | 0.0285 (7) | 0.0231 (7) | 0.0343 (7) | −0.0023 (5) | −0.0019 (5) | 0.0030 (5) |
C3 | 0.0257 (7) | 0.0333 (8) | 0.0453 (8) | 0.0002 (6) | −0.0029 (6) | 0.0010 (7) |
P1A | 0.0313 (3) | 0.0177 (4) | 0.0384 (4) | 0.0034 (3) | 0.0024 (3) | 0.0043 (3) |
O2A | 0.0366 (11) | 0.0231 (11) | 0.0610 (14) | 0.0061 (8) | 0.0015 (8) | 0.0068 (9) |
O3A | 0.0456 (14) | 0.0265 (12) | 0.0372 (9) | 0.0008 (8) | −0.0094 (9) | 0.0011 (7) |
O4A | 0.0430 (8) | 0.0243 (8) | 0.0409 (9) | 0.0049 (6) | 0.0152 (7) | 0.0033 (6) |
C2A | 0.0263 (9) | 0.0256 (12) | 0.0248 (18) | 0.0006 (8) | 0.0027 (13) | 0.0054 (13) |
C4A | 0.052 (2) | 0.0284 (12) | 0.0494 (10) | 0.0007 (15) | −0.0097 (18) | 0.0029 (9) |
C5A | 0.053 (3) | 0.0453 (18) | 0.0576 (14) | −0.0050 (17) | −0.012 (2) | 0.0038 (12) |
C6A | 0.0605 (13) | 0.0392 (11) | 0.0413 (14) | −0.0010 (10) | 0.0244 (14) | −0.0052 (12) |
C7A | 0.054 (3) | 0.0554 (12) | 0.045 (2) | −0.0040 (14) | 0.0188 (16) | 0.0094 (12) |
P1—O2 | 1.474 (2) | C1—C2A | 1.580 (15) |
P1—O3 | 1.5791 (16) | C3—C3i | 1.523 (3) |
P1—O4 | 1.5619 (15) | C3—H3A | 0.9900 |
P1—C2 | 1.801 (2) | C3—H3B | 0.9900 |
O3—C4 | 1.464 (3) | P1A—O2A | 1.473 (7) |
O4—C6 | 1.458 (3) | P1A—O3A | 1.570 (6) |
C2—H2A | 0.9900 | P1A—O4A | 1.581 (5) |
C2—H2B | 0.9900 | P1A—C2A | 1.760 (9) |
C2—C1 | 1.501 (5) | O3A—C4A | 1.435 (10) |
C4—H4A | 0.9900 | O4A—C6A | 1.413 (9) |
C4—H4B | 0.9900 | C2A—H2AA | 0.9900 |
C4—C5 | 1.502 (4) | C2A—H2AB | 0.9900 |
C5—H5A | 0.9800 | C4A—H4AA | 0.9900 |
C5—H5B | 0.9800 | C4A—H4AB | 0.9900 |
C5—H5C | 0.9800 | C4A—C5A | 1.489 (10) |
C6—H6A | 0.9900 | C5A—H5AA | 0.9800 |
C6—H6B | 0.9900 | C5A—H5AB | 0.9800 |
C6—C7 | 1.475 (6) | C5A—H5AC | 0.9800 |
C7—H7A | 0.9800 | C6A—H6AA | 0.9900 |
C7—H7B | 0.9800 | C6A—H6AB | 0.9900 |
C7—H7C | 0.9800 | C6A—C7A | 1.495 (12) |
O1—C1 | 1.2282 (17) | C7A—H7AA | 0.9800 |
N1—C1 | 1.3348 (18) | C7A—H7AB | 0.9800 |
N1—C3 | 1.4502 (19) | C7A—H7AC | 0.9800 |
N1—H1 | 0.832 (19) | ||
O2—P1—O3 | 113.34 (11) | N1—C1—C2A | 117.1 (6) |
O2—P1—O4 | 115.38 (11) | N1—C3—C3i | 111.71 (16) |
O2—P1—C2 | 113.46 (18) | N1—C3—H3A | 109.3 |
O3—P1—C2 | 106.70 (17) | N1—C3—H3B | 109.3 |
O4—P1—O3 | 103.93 (11) | C3i—C3—H3A | 109.3 |
O4—P1—C2 | 102.95 (16) | C3i—C3—H3B | 109.3 |
C4—O3—P1 | 118.74 (19) | H3A—C3—H3B | 107.9 |
C6—O4—P1 | 121.77 (14) | O2A—P1A—O3A | 117.5 (4) |
P1—C2—H2A | 109.5 | O2A—P1A—O4A | 115.7 (4) |
P1—C2—H2B | 109.5 | O2A—P1A—C2A | 110.4 (6) |
H2A—C2—H2B | 108.0 | O3A—P1A—O4A | 97.9 (4) |
C1—C2—P1 | 110.9 (2) | O3A—P1A—C2A | 108.6 (6) |
C1—C2—H2A | 109.5 | O4A—P1A—C2A | 105.6 (5) |
C1—C2—H2B | 109.5 | C4A—O3A—P1A | 119.8 (7) |
O3—C4—H4A | 110.0 | C6A—O4A—P1A | 119.0 (5) |
O3—C4—H4B | 110.0 | C1—C2A—P1A | 121.1 (8) |
O3—C4—C5 | 108.4 (3) | C1—C2A—H2AA | 107.1 |
H4A—C4—H4B | 108.4 | C1—C2A—H2AB | 107.1 |
C5—C4—H4A | 110.0 | P1A—C2A—H2AA | 107.1 |
C5—C4—H4B | 110.0 | P1A—C2A—H2AB | 107.1 |
C4—C5—H5A | 109.5 | H2AA—C2A—H2AB | 106.8 |
C4—C5—H5B | 109.5 | O3A—C4A—H4AA | 109.9 |
C4—C5—H5C | 109.5 | O3A—C4A—H4AB | 109.9 |
H5A—C5—H5B | 109.5 | O3A—C4A—C5A | 109.1 (9) |
H5A—C5—H5C | 109.5 | H4AA—C4A—H4AB | 108.3 |
H5B—C5—H5C | 109.5 | C5A—C4A—H4AA | 109.9 |
O4—C6—H6A | 109.9 | C5A—C4A—H4AB | 109.9 |
O4—C6—H6B | 109.9 | C4A—C5A—H5AA | 109.5 |
O4—C6—C7 | 108.9 (3) | C4A—C5A—H5AB | 109.5 |
H6A—C6—H6B | 108.3 | C4A—C5A—H5AC | 109.5 |
C7—C6—H6A | 109.9 | H5AA—C5A—H5AB | 109.5 |
C7—C6—H6B | 109.9 | H5AA—C5A—H5AC | 109.5 |
C6—C7—H7A | 109.5 | H5AB—C5A—H5AC | 109.5 |
C6—C7—H7B | 109.5 | O4A—C6A—H6AA | 109.4 |
C6—C7—H7C | 109.5 | O4A—C6A—H6AB | 109.4 |
H7A—C7—H7B | 109.5 | O4A—C6A—C7A | 111.1 (13) |
H7A—C7—H7C | 109.5 | H6AA—C6A—H6AB | 108.0 |
H7B—C7—H7C | 109.5 | C7A—C6A—H6AA | 109.4 |
C1—N1—C3 | 120.79 (12) | C7A—C6A—H6AB | 109.4 |
C1—N1—H1 | 119.9 (13) | C6A—C7A—H7AA | 109.5 |
C3—N1—H1 | 119.3 (13) | C6A—C7A—H7AB | 109.5 |
O1—C1—C2 | 122.4 (2) | C6A—C7A—H7AC | 109.5 |
O1—C1—N1 | 122.64 (13) | H7AA—C7A—H7AB | 109.5 |
O1—C1—C2A | 119.3 (6) | H7AA—C7A—H7AC | 109.5 |
N1—C1—C2 | 114.9 (2) | H7AB—C7A—H7AC | 109.5 |
P1—O3—C4—C5 | −160.9 (3) | C1—N1—C3—C3i | 77.0 (2) |
P1—O4—C6—C7 | 170.3 (4) | C3—N1—C1—C2 | −176.50 (16) |
P1—C2—C1—O1 | 71.4 (3) | C3—N1—C1—O1 | 0.4 (2) |
P1—C2—C1—N1 | −111.8 (2) | C3—N1—C1—C2A | 169.1 (4) |
O2—P1—O3—C4 | −45.5 (3) | P1A—O3A—C4A—C5A | −172.5 (10) |
O2—P1—O4—C6 | −48.7 (2) | P1A—O4A—C6A—C7A | 165.3 (11) |
O2—P1—C2—C1 | 174.3 (2) | O2A—P1A—O3A—C4A | −44.3 (11) |
O3—P1—O4—C6 | 76.0 (2) | O2A—P1A—O4A—C6A | 40.5 (6) |
O3—P1—C2—C1 | 48.8 (3) | O2A—P1A—C2A—C1 | 172.8 (8) |
O4—P1—O3—C4 | −171.6 (2) | O3A—P1A—O4A—C6A | 166.2 (6) |
O4—P1—C2—C1 | −60.3 (3) | O3A—P1A—C2A—C1 | 42.7 (11) |
C2—P1—O3—C4 | 80.1 (3) | O4A—P1A—O3A—C4A | −168.7 (8) |
C2—P1—O4—C6 | −172.9 (2) | O4A—P1A—C2A—C1 | −61.4 (11) |
O1—C1—C2A—P1A | 76.3 (10) | C2A—P1A—O3A—C4A | 81.9 (10) |
N1—C1—C2A—P1A | −92.8 (9) | C2A—P1A—O4A—C6A | −81.9 (7) |
Symmetry code: (i) −x+2, −y, −z+1. |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1···O2ii | 0.832 (19) | 2.05 (2) | 2.883 (2) | 175.0 (18) |
N1—H1···O2Aii | 0.832 (19) | 1.92 (2) | 2.741 (8) | 170.2 (18) |
Symmetry code: (ii) x+1/2, −y+1/2, −z+1. |
Acknowledgements
The authors thank Pfizer, Inc. for the donation of a Varian INOVA 400 F T NMR. The CCD-based X-ray diffractometers at Michigan State University were upgraded and/or replaced by departmental funds.
Funding information
Funding for this research was provided by: National Science Foundation (grant No. MRI CHE-1725699; grant No. REU CHE-1092944 to A. VanderWeide); Grand Valley State University (OURS, CSCE, Chemistry Department's Weldon Fund).
References
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