Synthesis and crystal structure of a novel prochiral keto­imine: (E)-aceto­phenone O-di­phenyl­phosphoryl oxime

A novel activated prochiral keto­imine, (E)-aceto­phenone O-di­phenyl­phosphoryl oxime, C₂₀H₁₈NO₂P, with an electron-withdrawing substituent on the imine N atom similar to other prochiral ketoimines, has been synthesized and the X-ray crystal stucture determined. The molecules pack together in the solid state via weak intermolecular C—H...O interactions and both face-to-face and edge-to-face π-stacking interactions.

S1. Introduction

Asymmetric chemical synthesis methodologies that produce chiral resolved organic compounds have been of inter­est to chemists and chemical industry for many years (Blaser & Elke, 2004; Walsh & Kowzlowski, 2008). Treating compounds that contain prochiral carbonyl and imine carbon centers with nucleophiles, for example, has proven to be a valuable method for the synthesis of compounds with stereogenic centers (Silverio et al., 2013). Aldehydes and ketones may be used to produce chiral secondary alcohols (Baker-Salisbury et al., 2014) and tertiary alcohols (Garcia et al., 2002), respectively. Aldimine and keto­imine substrates may be used to prepare, respectively, chiral tertiary (Bonnaventure & Charette, 2009; Soai et al., 1992) and quaternary (Cogan & Ellman, 1999) hydro­carbon substituents on amines. In contrast to aldehyde and ketone addition reactions, much less has been reported about imine addition (Fu et al., 2008; Nishimura et al., 2012). Whereas coordination of a Lewis acid can be sufficient for aldehyde and ketone activation, previously published studies have shown that it is generally only possible to asymmetrically add a nucleophile to the imine C═N carbon when the imine is suitably activated (Weinreb & Orr, 2005). Such activation is required as the imine C═N bond is less reactive than a carbonyl C═O bond, for example, because it is less polar, although it is a weaker and longer bond than carbonyl C═O. Activated imine precursors that have proven useful in asymmetric synthesis include (a) N-sulfonyl­imines, (b) tert-butane­sulfinyl keto­imines, and (c) N-phospho­ryl­imines (see Scheme 1).

Adding to the list of activated imine substrates for use in asymmetric organic synthesis, in this paper, we report the synthesis, characterization and crystal structure of a novel activated prochiral keto­imine substrate, namely (E)-aceto­phenone O-di­phenyl­phospho­ryl oxime, (I).

S2. Experimental

S2.1. General considerations

Aceto­phenone oxime (95%), di­phenyl­phosphinic chloride (98%), and tri­ethyl­amine (99.5%) were obtained from Sigma–Aldrich and were used as received. ¹H, ¹³C{¹H} and ³¹P{¹H} NMR spectra were recorded at room temperature using a Bruker Avance DPX 300 MHz spectrometer. ¹H chemical shifts are reported in p.p.m. referenced to TMS (δ 0.0 p.p.m.) for chloro­form-d. ¹³C chemical shifts are reported in p.p.m. referenced to the solvent resonance of δ 77.0 p.p.m. for chloro­form-d. ³¹P chemical shifts are reported referenced to an inter­nal standard of 85% H₃PO₄ in water, δ 0.0 p.p.m. IR spectra were recorded neat by ATR on a Thermo Nicolet iS50 FT–IR spectrometer and are reported in cm^-1. Elemental analyses were carried out by Robertson Microlit Laboratories, Ledgewood, NJ, USA. GC–MS data were obtained with an Agilent 7890 GC/ 5975 MS in di­chloro­methane. For LC–MS analysis, the sample dissolved in CHCl₃–CH₃OH–H₂O–NH₄OH (600:340:50:5 v/v/v/v) was directly infused using an Agilent 1100 HPLC system into an Agilent 6520 electrospray ionization quadrupole time-of-flight mass spectrometer detecting in the negative ion mode. LC–MS data was obtained using settings described previously (Bulat & Garrett, 2011).

S2.2. Synthesis and crystallization (see Scheme 2)

Following a procedure similar to that reported for the synthesis of N-di­phenyl­phosphinoyl keto­imines (Huang et al., 2007), the title compound was prepared by the following procedure, as shown in Scheme 2. (E)-Aceto­phenone oxime (2.028 g, 15 mmol) was dissolved in dry dicholo­methane (15 ml) in a Schlenk tube, cooled to 228 K, and treated with anhydrous tri­ethyl­amine (2.09 ml, 15 mmol) while stirring. Di­phenyl­phosphinic chloride (2.86 ml, 15 mmol) dissolved in dry di­chloro­methane (5 ml) was then added dropwise by syringe over a period of 10 min. The mixture was allowed to warm to room temperature and was stirred for an additional hour. The solvent was removed on a vacuum line, and the residue was redissolved in fresh dry di­chloro­methane. This solution was washed and extracted from 1 M KHSO₄, saturated NaHCO₃ and saturated NaCl (2 × 20 ml each), dried over anhydrous MgSO₄, filtered, and the solvent removed on a rotary evaporator. The resulting off-white powder (2.235 g) represented a 43% yield. Crystals of (E)-aceto­phenone O-di­phenyl­phospho­ryl oxime, (I), were grown by slow evaporation from an aceto­nitrile solution.

S2.3. Spectrosopic and analytical data

¹H NMR (300 MHz, CDCl₃): δ 7.3–7.9 (m, 15H, C_arylH), 2.46 (s, 3H, CH₃). ¹³C NMR (¹³C{¹H}, 75.5 MHz, CDCl₃): δ 14.01 (CH₃), 126.84 (C_arylH), 128.34 (d, C_arylH, J_C—P = 2 Hz), 128.51 (C_arylH), 130.33 (C_arylH), 131.61 (d, C_aryl, J_C—P = 136 Hz), 132.02 (d, C_arylH, J_C—P = 10 Hz), 132.24 (d, C_arylH, J_C—P = 3 Hz), 134.55 (C_aryl), 163.65 (d, C═N, J_C—P = 12 Hz). ³¹P NMR (³¹P{¹H}, 121.5 MHz, CDCl₃): δ 35.24. IR (neat, cm^-1): 3050.8 (w, C_aryl—H str), 1685.4 (w, C═N str), 1591.8 (w), 1570.0 (w), 1495.6 (w), 1485.4 (w), 1438.7 (m), 1374.2 (w), 1305.0 (m), 1223.7 (s), 1186.7 (w), 1129.7 (m), 1115.1 (m), 1075.7 (w), 1028.1 (w), 985.2 (w), 961.8 (w), 896.2 (s), 851.2 (s), 761.1 (m), 753.3 (m), 728.5 (s), 687.6 (s), 623.7 (m), 614.5 (m), 551.3 (s), 521.6 (s), 455.7 (m), 434.3 (m). Analysis calculated for C₂₀H₁₈NO₂P: C 71.63, H 5.41, N 4.18%; found: C 71.37, H 5.35, N 4.01%. GC–MS: M⁺ 335 (calculated exact mass = 335.11). LC–MS: the m/z observed for the [M - H]⁺ ion was 336.1149 (calculated exact mass = 336.1148); this value of m/z matches the molecular formula with 0.30 p.p.m. error.

S2.4. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 1. H atoms on C atoms were included in calculated positions and refined using a riding model, with C—H = 0.95 or 0.98 Å and U_iso(H) = 1.2 and 1.5 times U_eq(C) for the aryl and methyl C atoms, respectively. The extinction parameter (EXTI) refined to zero and was removed from the refinement.

S3. Results and discussion

\ (E)-Aceto­phenone O-di­phenyl­phospho­ryl oxime, (I), was prepared by treating (E)-aceto­phenone oxime with di­phenyl­phosphinic chloride in the presence of tri­ethyl­amine, forming tri­ethyl­amine hydro­chloride as the by-product (Scheme 2). After appropriately washing the product of the crude reaction mixture, it was possible to isolate the compound cleanly without the need for column chromatography. The stability and isolability of activated keto­imine substrates are know to be important features of their utility in organic synthesis (Weinreb & Orr, 2005). ¹H, ¹³C and ³¹P NMR, as well as GC–MS, LC–MS and elemental analysis, are all consistent with the structure of (I). The imine C═N stretch can be seen in the IR spectrum at 1685.4 cm^-1. The syntheses of the analogous O-di­phenyl­phospho­ryl oximes prepared from benzopehnone (Brown et al., 1976) and acetone (Harger, 1979) have been reported previously. Notably, we found that the method reported for the synthesis of the acetone analog 2-propanone O-(di­phenyl­phospho­ryl) oxime (Harger, 1979), by treating the ketone with O-(di­phenyl­phospho­ryl)hydroxyl­amine, was not effective with aceto­phenone.

The title compound recrystallizes by slow evaporation of di­chloro­methane or aceto­nitrile, yielding crystals suitable for single-crystal X-ray diffraction analysis. A single independent molecule of (I) is found in the asymmetric unit (Fig. 1), with a C═N bond length of 1.2835 (19) Å. This is in close agreement with the analogous bond in other activated keto­imines, such as (i) N-sulfonyl­imines: N-tosyl (α-methyl­benzyl)­imine with a C═N bond length of 1.288 Å (Charette & Giroux, 1996) and N-tosyl (α-ethyl­benzyl)­imine with a C═N bond length of 1.284 (2) Å (Fan et al., 2008); (ii) tert-butane­sulfinyl keto­imines: (R_S,S)-N-(3-hy­droxy-1,3-di­phenyl­propyl­idene)-\ tert-butane­sulfinamide with a C═N bond length of 1.288 (3) Å (Kochi et al., 2002) and N-[1-(4-chloro­phenyl)­ethyl­idene]-2-methyl­propane-2-sulfinamide with a C═N bond length of 1.283 (2) Å (Guo et al., 2013); (iii) N-phosphinoyl­imines: tert-butyl (Z)-N-{(2S)-1-[(di­phenyl­phosphinoyl)imino]-1-phenyl-2-\ propyl}­carbamate with a C═N bond length of 1.260 (6) Å (Kohmura & Mase, 2004); and (iv) the α-keto­imine ester (2-meth­oxy­phenyl­imino)­phenyl­acetic acid methyl ester, with a C═N bond length of 1.271 (3) Å (Fu et al., 2008). The structure confirms the compound is the E diastereomer of the C═N double bond.

The molecular packing of (I) is such that phospho­ryl atom O2 is on the same side of the molecule as the imine N atom, with an N1—O1—P1—O2 torsion angle of 63.26 (10)°. The molecules pack together in the solid state with few strong inter­molecular inter­actions, such that the packing is likely driven to best fit the molecular shape of the molecule. Phospho­ryl atom O2 forms two weak long C—H···O inter­actions (Table 2 and Fig. 2) running parallel to the crystallograhpic b axis, and there are several aromatic π-stacking inter­actions. One of the di­phenyl­phospho­ryl phenyl rings forms a pairwise face-to-face π-stacking inter­action with the equivalent ring at (-x+2, -y+1, -z+1) on a neighboring molecule (Fig. 2). This π-stacking is characterized by a centroid-to-centroid distance of 3.953 (1) Å, a plane-to-centroid distance of 3.947 (1) Å, and a ring offset or ring-slippage distance of 0.216 (3) Å (Hunter & Saunders, 1990; Lueckheide et al., 2013). There also exists edge-to-face π-stacking inter­actions (Nishio et al., 2009; Lueckheide et al., 2013) of each of the parallel π-stacked rings with the other di­phenyl­phospho­ryl ring on the neighboring molecule at (-x+1, -y+1, -z+1), characterized by centroid-to-centroid distances of 4.823 (1) Å (Fig. 2). This edge-to-face π-stacking inter­action is highly offseet, with a plane-to-plane angle of 116.0 (1)°. Combined with the face-to-face π-stacking inter­action, these edge-to-face inter­actions lead to the endo-face-to-endo-face assembly shown in Fig. 2. An example of a similar endo-face-to-endo-face assembly can be found in the crystal structure of 1,4,9,12-tetra­bromo-6,7,14,15-tetra­hydro-6,14-methano­cyclo­octa­[1,2-b:\ 5,6-b']di­quinoline (Marjo et al., 2001). Further, there is an edge-to-face π-stacking inter­action between the aceto­phenone ring and one of the di­phenyl­phosphinyl phenyl rings at (-x+1, y-1/2, -z+1/2), characterized by a plane-to-plane angle of 98.63 (5)° and a centroid-to-centroid distance of 4.943 (1) Å. The edge-to-face inter­actions found in the structure of (I) are all slightly shorter than the edge-to-face centroid-to-centroid distance of 5.025 Å found in the herringbone packing motif in the crystal structure of benzene (Bacon et al., 1964).

In conclusion, we have prepared and obtained the crystal structure of (E)-aceto­phenone O-di­phenyl­phospho­ryl oxime, a keto­imine with an electron-withdrawing substituent on the imine N atom similar to other prochiral keto­imines used in asymmetric organic synthesis such as N-sulfonyl­imines, tert-butane­sulfinyl keto­imines, and N-phospho­ryl­imines.

Computing details

Data collection: APEXII (Bruker, 2013); cell refinement: SAINT (Bruker, 2013); data reduction: SAINT (Bruker, 2013); program(s) used to solve structure: SHELXTL2014 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: SHELXTL2014 (Sheldrick, 2008); software used to prepare material for publication: SHELXTL2014 (Sheldrick, 2008), Mercury (Macrae et al., 2008) and OLEX2 (Dolomanov et al., 2009).

Figures

	Fig. 1. A view of the title compound, showing the atom-numbering scheme. Displacement ellipsoids are shown at the 50% probability level.
	Fig. 2. A view of the molecular packing of (I), showing the weak C—H···O interactions (dashed lines), the edge-to-face π-stacking (thin lines indicating centroid-to-centroid interactions) and the face-to-face π-stacking (thick line indicates centroid-to-centroid). For symmetry code (i), see Table 2.

(E)-Acetophenone O-diphenylphosphoryl oxime

Crystal data

C20H18NO2P	F(000) = 704
Mr = 335.32	Dx = 1.316 Mg m^−3
Monoclinic, P21/c	Cu Kα radiation, λ = 1.54178 Å
a = 18.035 (2) Å	Cell parameters from 9927 reflections
b = 5.9874 (7) Å	θ = 5.1–71.2°
c = 16.236 (2) Å	µ = 1.53 mm^−1
β = 105.133 (3)°	T = 125 K
V = 1692.4 (4) Å^3	Block, colourless
Z = 4	0.24 × 0.24 × 0.18 mm

Data collection

Bruker APEXII CCD diffractometer	2983 independent reflections
Radiation source: Cu IuS micro-focus source	2928 reflections with I > 2σ(I)
Detector resolution: 8.3333 pixels mm^-1	Rint = 0.028
ϕ and ω scans	θmax = 66.6°, θmin = 2.5°
Absorption correction: multi-scan (SADABS; Bruker, 2013)	h = −21→21
Tmin = 0.65, Tmax = 0.77	k = −7→7
21556 measured reflections	l = −19→19

Refinement

Refinement on F^2	0 restraints
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.034	H-atom parameters constrained
wR(F^2) = 0.091	w = 1/[σ^2(Fo^2) + (0.0506P)^2 + 0.8622P] where P = (Fo^2 + 2Fc^2)/3
S = 1.05	(Δ/σ)max = 0.001
2983 reflections	Δρmax = 0.37 e Å^−3
218 parameters	Δρmin = −0.41 e Å^−3

Special details

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
P1	0.79223 (2)	0.73014 (6)	0.44821 (2)	0.01700 (13)
O1	0.73272 (5)	0.56856 (17)	0.47829 (6)	0.0217 (2)
O2	0.78013 (6)	0.97337 (17)	0.45212 (6)	0.0241 (2)
N1	0.65565 (6)	0.5957 (2)	0.42301 (7)	0.0227 (3)
C1	0.63352 (9)	0.2818 (3)	0.51181 (11)	0.0333 (4)
H1A	0.6761	0.3392	0.5575	0.05*
H1B	0.65	0.1463	0.4877	0.05*
H1C	0.5899	0.2466	0.5351	0.05*
C2	0.60996 (8)	0.4545 (2)	0.44351 (9)	0.0221 (3)
C3	0.52946 (8)	0.4688 (3)	0.39011 (9)	0.0239 (3)
C4	0.47876 (9)	0.2904 (3)	0.38606 (12)	0.0340 (4)
H4A	0.4943	0.1635	0.4215	0.041*
C5	0.40559 (10)	0.2973 (3)	0.33054 (13)	0.0418 (4)
H5A	0.3716	0.175	0.3282	0.05*
C6	0.38203 (9)	0.4810 (3)	0.27875 (11)	0.0375 (4)
H6A	0.3326	0.483	0.2396	0.045*
C7	0.43081 (9)	0.6620 (3)	0.28428 (10)	0.0322 (4)
H7A	0.4141	0.7907	0.2502	0.039*
C8	0.50389 (8)	0.6563 (3)	0.33928 (10)	0.0265 (3)
H8A	0.537	0.7812	0.3425	0.032*
C9	0.87870 (7)	0.6387 (2)	0.52316 (8)	0.0188 (3)
C10	0.93634 (8)	0.7970 (3)	0.55111 (10)	0.0270 (3)
H10A	0.9305	0.9427	0.5271	0.032*
C11	1.00225 (9)	0.7425 (3)	0.61392 (11)	0.0356 (4)
H11A	1.0417	0.8504	0.6324	0.043*
C12	1.01050 (9)	0.5317 (3)	0.64950 (10)	0.0325 (4)
H12A	1.055	0.4959	0.6936	0.039*
C13	0.95397 (9)	0.3719 (3)	0.62099 (10)	0.0295 (3)
H13A	0.9601	0.2266	0.6453	0.035*
C14	0.88845 (8)	0.4231 (2)	0.55705 (9)	0.0234 (3)
H14A	0.8505	0.3121	0.5365	0.028*
C15	0.79263 (7)	0.6418 (2)	0.34267 (8)	0.0174 (3)
C16	0.81433 (8)	0.7996 (2)	0.29041 (9)	0.0204 (3)
H16A	0.8283	0.9459	0.3115	0.024*
C17	0.81572 (9)	0.7447 (2)	0.20781 (9)	0.0241 (3)
H17A	0.8307	0.8529	0.1725	0.029*
C18	0.79517 (8)	0.5311 (2)	0.17697 (9)	0.0230 (3)
H18A	0.7953	0.4935	0.1201	0.028*
C19	0.77453 (8)	0.3728 (2)	0.22920 (9)	0.0226 (3)
H19A	0.761	0.2264	0.208	0.027*
C20	0.77337 (8)	0.4256 (2)	0.31232 (9)	0.0207 (3)
H20A	0.7596	0.3159	0.348	0.025*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
P1	0.0171 (2)	0.0187 (2)	0.01512 (19)	0.00034 (12)	0.00400 (13)	−0.00044 (12)
O1	0.0157 (5)	0.0300 (5)	0.0188 (5)	−0.0003 (4)	0.0034 (4)	0.0036 (4)
O2	0.0280 (5)	0.0209 (5)	0.0226 (5)	0.0030 (4)	0.0052 (4)	−0.0016 (4)
N1	0.0163 (6)	0.0299 (6)	0.0209 (6)	0.0007 (5)	0.0031 (5)	0.0020 (5)
C1	0.0272 (8)	0.0396 (9)	0.0351 (9)	0.0010 (7)	0.0116 (7)	0.0120 (7)
C2	0.0217 (7)	0.0248 (7)	0.0226 (7)	0.0005 (6)	0.0107 (5)	−0.0014 (6)
C3	0.0206 (7)	0.0278 (8)	0.0262 (7)	−0.0014 (6)	0.0114 (6)	−0.0043 (6)
C4	0.0268 (8)	0.0262 (8)	0.0517 (10)	−0.0023 (6)	0.0150 (7)	−0.0019 (7)
C5	0.0234 (8)	0.0364 (9)	0.0661 (12)	−0.0091 (7)	0.0129 (8)	−0.0158 (9)
C6	0.0196 (7)	0.0477 (10)	0.0432 (9)	0.0005 (7)	0.0046 (7)	−0.0155 (8)
C7	0.0222 (7)	0.0446 (10)	0.0297 (8)	0.0030 (7)	0.0067 (6)	−0.0009 (7)
C8	0.0209 (7)	0.0325 (8)	0.0275 (7)	−0.0024 (6)	0.0089 (6)	0.0003 (6)
C9	0.0181 (6)	0.0235 (7)	0.0156 (6)	0.0013 (5)	0.0057 (5)	−0.0030 (5)
C10	0.0228 (7)	0.0265 (8)	0.0306 (8)	−0.0031 (6)	0.0051 (6)	−0.0001 (6)
C11	0.0198 (8)	0.0394 (9)	0.0428 (10)	−0.0044 (7)	−0.0006 (7)	−0.0070 (7)
C12	0.0221 (7)	0.0408 (9)	0.0295 (8)	0.0096 (7)	−0.0024 (6)	−0.0075 (7)
C13	0.0321 (8)	0.0271 (8)	0.0264 (8)	0.0102 (6)	0.0027 (6)	−0.0007 (6)
C14	0.0248 (7)	0.0227 (7)	0.0216 (7)	0.0005 (6)	0.0041 (5)	−0.0031 (6)
C15	0.0143 (6)	0.0204 (7)	0.0167 (6)	0.0019 (5)	0.0025 (5)	0.0008 (5)
C16	0.0205 (7)	0.0190 (7)	0.0216 (7)	0.0001 (5)	0.0054 (5)	0.0008 (5)
C17	0.0278 (8)	0.0245 (8)	0.0223 (7)	0.0017 (6)	0.0108 (6)	0.0047 (5)
C18	0.0251 (7)	0.0278 (8)	0.0160 (6)	0.0050 (6)	0.0053 (5)	0.0004 (6)
C19	0.0247 (7)	0.0200 (7)	0.0214 (7)	0.0005 (6)	0.0030 (5)	−0.0032 (5)
C20	0.0218 (7)	0.0202 (7)	0.0195 (6)	−0.0009 (5)	0.0044 (5)	0.0027 (5)

Geometric parameters (Å, º)

P1—O2	1.4764 (11)	C9—C10	1.392 (2)
P1—O1	1.6124 (10)	C9—C14	1.396 (2)
P1—C9	1.7949 (14)	C10—C11	1.388 (2)
P1—C15	1.7951 (13)	C10—H10A	0.95
O1—N1	1.4535 (14)	C11—C12	1.380 (3)
N1—C2	1.2835 (19)	C11—H11A	0.95
C1—C2	1.495 (2)	C12—C13	1.386 (2)
C1—H1A	0.98	C12—H12A	0.95
C1—H1B	0.98	C13—C14	1.388 (2)
C1—H1C	0.98	C13—H13A	0.95
C2—C3	1.4863 (19)	C14—H14A	0.95
C3—C4	1.396 (2)	C15—C16	1.3922 (19)
C3—C8	1.399 (2)	C15—C20	1.3965 (19)
C4—C5	1.391 (2)	C16—C17	1.388 (2)
C4—H4A	0.95	C16—H16A	0.95
C5—C6	1.382 (3)	C17—C18	1.388 (2)
C5—H5A	0.95	C17—H17A	0.95
C6—C7	1.384 (3)	C18—C19	1.386 (2)
C6—H6A	0.95	C18—H18A	0.95
C7—C8	1.386 (2)	C19—C20	1.391 (2)
C7—H7A	0.95	C19—H19A	0.95
C8—H8A	0.95	C20—H20A	0.95
O2—P1—O1	117.47 (6)	C10—C9—P1	117.14 (11)
O2—P1—C9	112.56 (6)	C14—C9—P1	123.15 (11)
O1—P1—C9	98.10 (6)	C11—C10—C9	120.20 (15)
O2—P1—C15	111.66 (6)	C11—C10—H10A	119.9
O1—P1—C15	106.34 (6)	C9—C10—H10A	119.9
C9—P1—C15	109.76 (6)	C12—C11—C10	120.04 (15)
N1—O1—P1	110.53 (8)	C12—C11—H11A	120.0
C2—N1—O1	109.96 (11)	C10—C11—H11A	120.0
C2—C1—H1A	109.5	C11—C12—C13	120.12 (14)
C2—C1—H1B	109.5	C11—C12—H12A	119.9
H1A—C1—H1B	109.5	C13—C12—H12A	119.9
C2—C1—H1C	109.5	C12—C13—C14	120.36 (15)
H1A—C1—H1C	109.5	C12—C13—H13A	119.8
H1B—C1—H1C	109.5	C14—C13—H13A	119.8
N1—C2—C3	113.98 (13)	C13—C14—C9	119.59 (14)
N1—C2—C1	124.80 (13)	C13—C14—H14A	120.2
C3—C2—C1	121.17 (13)	C9—C14—H14A	120.2
C4—C3—C8	118.37 (14)	C16—C15—C20	119.83 (12)
C4—C3—C2	120.77 (14)	C16—C15—P1	116.99 (10)
C8—C3—C2	120.77 (13)	C20—C15—P1	123.18 (10)
C5—C4—C3	120.44 (16)	C17—C16—C15	120.48 (13)
C5—C4—H4A	119.8	C17—C16—H16A	119.8
C3—C4—H4A	119.8	C15—C16—H16A	119.8
C6—C5—C4	120.47 (16)	C16—C17—C18	119.78 (13)
C6—C5—H5A	119.8	C16—C17—H17A	120.1
C4—C5—H5A	119.8	C18—C17—H17A	120.1
C5—C6—C7	119.62 (15)	C19—C18—C17	119.89 (13)
C5—C6—H6A	120.2	C19—C18—H18A	120.1
C7—C6—H6A	120.2	C17—C18—H18A	120.1
C6—C7—C8	120.26 (16)	C18—C19—C20	120.83 (13)
C6—C7—H7A	119.9	C18—C19—H19A	119.6
C8—C7—H7A	119.9	C20—C19—H19A	119.6
C7—C8—C3	120.78 (15)	C19—C20—C15	119.18 (13)
C7—C8—H8A	119.6	C19—C20—H20A	120.4
C3—C8—H8A	119.6	C15—C20—H20A	120.4
C10—C9—C14	119.62 (13)
O2—P1—O1—N1	63.26 (10)	C15—P1—C9—C14	−81.80 (12)
C9—P1—O1—N1	−176.03 (8)	C14—C9—C10—C11	−1.7 (2)
C15—P1—O1—N1	−62.60 (9)	P1—C9—C10—C11	175.03 (12)
P1—O1—N1—C2	175.14 (9)	C9—C10—C11—C12	−0.7 (2)
O1—N1—C2—C3	−179.77 (11)	C10—C11—C12—C13	1.8 (3)
O1—N1—C2—C1	−2.34 (19)	C11—C12—C13—C14	−0.5 (2)
N1—C2—C3—C4	160.60 (14)	C12—C13—C14—C9	−1.8 (2)
C1—C2—C3—C4	−16.9 (2)	C10—C9—C14—C13	2.9 (2)
N1—C2—C3—C8	−16.02 (19)	P1—C9—C14—C13	−173.61 (11)
C1—C2—C3—C8	166.44 (14)	O2—P1—C15—C16	26.35 (12)
C8—C3—C4—C5	2.1 (2)	O1—P1—C15—C16	155.67 (10)
C2—C3—C4—C5	−174.57 (15)	C9—P1—C15—C16	−99.19 (11)
C3—C4—C5—C6	−0.1 (3)	O2—P1—C15—C20	−154.43 (11)
C4—C5—C6—C7	−2.1 (3)	O1—P1—C15—C20	−25.11 (12)
C5—C6—C7—C8	2.2 (2)	C9—P1—C15—C20	80.04 (12)
C6—C7—C8—C3	−0.2 (2)	C20—C15—C16—C17	1.1 (2)
C4—C3—C8—C7	−2.0 (2)	P1—C15—C16—C17	−179.65 (11)
C2—C3—C8—C7	174.72 (13)	C15—C16—C17—C18	0.1 (2)
O2—P1—C9—C10	−23.40 (13)	C16—C17—C18—C19	−1.0 (2)
O1—P1—C9—C10	−147.71 (11)	C17—C18—C19—C20	0.6 (2)
C15—P1—C9—C10	101.62 (12)	C18—C19—C20—C15	0.6 (2)
O2—P1—C9—C14	153.18 (11)	C16—C15—C20—C19	−1.46 (19)
O1—P1—C9—C14	28.87 (12)	P1—C15—C20—C19	179.34 (10)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C14—H14A···O2^i	0.95	2.59	3.4973 (18)	161
C20—H20A···O2^i	0.95	2.62	3.5150 (17)	157

Symmetry code: (i) x, y−1, z.