Crystal structure of dioxidobis(pentane-2,4-dionato-κ2O,O′)[1-phenyl-3-(pyridin-4-yl)propane-κN]uranium(VI)

Kawasaki, T.; Kitazawa, T.

doi:10.1107/S2056989014026607

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Volume 71| Part 1| January 2015| Pages 42-44

https://doi.org/10.1107/S2056989014026607

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Crystal structure of dioxidobis(pentane-2,4-dionato-κ²O,O′)[1-phenyl-3-(pyridin-4-yl)propane-κN]uranium(VI)

Takeshi Kawasaki ^a and Takafumi Kitazawa ^a,^b ^*

^aDepartment of Chemistry, Faculty of Science, Toho University, 2-2-1 Miyama, Funabashi, Chiba 274-8510, Japan, and ^bResearch Center for Materials with Integrated Properties, Toho University, Miyama, Funabashi, Chiba 274-8510, Japan
^*Correspondence e-mail: kitazawa@chem.sci.toho-u.ac.jp

Edited by A. M. Chippindale, University of Reading, England (Received 23 October 2014; accepted 3 December 2014; online 1 January 2015)

In the title compound, [UO₂(C₅H₇O₂)₂(C₁₄H₁₅N)], the uranyl(VI) unit ([O=U=O]²⁺) is coordinated to two acetylacetonate (acac) anions and one 1-phenyl-3-(pyridin-4-yl)propane (ppp) molecule. The geometry around the U atom is UNO₆ pentagonal–bipyramidal; two uranyl(VI) O atoms are located at the axial positions, whereas four O atoms from two chelating bidentate acac ligands and one N atom of a ppp ligand form the equatorial plane.

Keywords: crystal structure; pentane-2,4-dionate; 1-phenyl-3-(pyridin-4-yl)propane; uranium(VI) complex.

CCDC reference: 1037284

1. Chemical context

The structural properties of uranyl(VI) complexes are interesting from the viewpoint of nuclear fuels reprocessing and actinide waste treatment. In most commercial reprocessing plants, spent nuclear fuels are treated by the Purex method, in which uranium and plutonium are extracted from a nitric acid solution of spent nuclear fuels using tributyl-phosphate/n-dodecane. Uranium in the nitric acid solution exists as uranyl(VI) ([O=U=O]²⁺) complexes. However, the Purex method has a few problems; for example, as the processing takes place on a relatively large scale, a large amount of extractant is necessary (Ikeda et al., 2004 ; Suzuki et al., 2012 ) Attempts to find other suitable coordinating ligands are therefore being undertaken. A number of structural studies of uranyl(VI) β-diketonate complexes have been reported by ourselves and others (Alcock et al., 1984 , 1987 ; Huuskonen et al., 2007 ; Kannan et al., 2001 ; Kawasaki & Kitazawa, 2008 ; Kawasaki et al., 2010 ; Sidorenko et al., 2009 ; Tahir et al., 2006 ; Takao & Ikeda, 2008 ). In particular, acetylacetonate (acac), is the simplest β-diketonate ligand and an important coordinating ligand for uranium.

We report herein the synthesis and crystal structure of a novel uranyl(VI) acetylacetonate (acac) complex with the pyridine-based ligand ppp [ppp = 1-phenyl-3-(pyridin-4-yl)propane] (Seth, 2014 ), namely, [UO₂(acac)₂(ppp)].

2. Structural commentary

The title compound of formula [UO₂(C₅H₇O₂)₂(C₁₄H₁₅N)], is constructed from one uranyl(VI) ([O=U=O]²⁺) unit, two acetylacetonate anions and one molecule of ppp (Fig. 1). The uranium(VI) atom exhibits a pentagonal–bipyramidal coordination geometry: two uranyl(VI) oxygen atoms (O1 and O2) are located in the axial positions and four oxygen atoms (O3, O4, O5 and O6) from two chelating bidentate acac ions, together with one nitrogen atom (N1) of the ppp molecule, form the equatorial plane. The bond lengths around U1 (Table 1) decrease in the order U—N > U—O_acac > U=O. The dihedral angle between the pyridine ring of the ppp molecule and the equatorial plane around U1 is 49.43 (12)°. The above structural properties are similar to those in the majority of previously characterised [UO₂(acac)₂L] (L = pyridine derivative ligand) complexes (Alcock et al., 1984; Kawasaki & Kitazawa, 2008; Kawasaki et al., 2010). The conformation of the ppp molecule is GG′ (Fig. 2). The dihedral angle between the pyridine ring and the phenyl ring in the ppp molecule is 26.96 (13)°.

Table 1
Selected geometric parameters (Å, °)

U1—O1	1.773 (3)	U1—O5	2.348 (2)
U1—O2	1.777 (3)	U1—O6	2.354 (2)
U1—O3	2.330 (2)	U1—N1	2.610 (3)
U1—O4	2.360 (2)

O1—U1—O2	179.19 (11)	O1—U1—N1	86.45 (11)
O3—U1—O4	70.88 (9)	O2—U1—N1	92.74 (11)
O3—U1—O6	138.83 (9)	O3—U1—N1	69.37 (9)
O4—U1—O5	79.13 (9)	O6—U1—N1	70.15 (9)
O5—U1—O6	70.91 (9)

Figure 1
The molecular structure of [UO₂(acac)₂(ppp)]. Displacement ellipsoids are drawn at the 50% probability level and H atoms have been omitted for clarity.

Figure 2
The four possible conformations that the ppp ligand can form (based on Carlucci et al., 2002

). In the title compound, the conformation is GG′.

3. Supramolecular features

A packing diagram of title complex is shown in Fig. 3. The molecules are stacked along the b axis, held together by van der Waals' interactions only. Significant intermolecular π–π and C—H⋯π interactions are not found.

Figure 3
A packing diagram of the title complex (red line: a axis; green line: b axis; blue line: c axis). Displacement ellipsoids are drawn at the 50% probability level and H atoms have been omitted for clarity.

4. Synthesis and crystallization

The title complex was synthesized according to literature procedures (Alcock et al., 1984, 1987; Kawasaki & Kitazawa, 2008; Kawasaki et al., 2010). To 10 ml of a methanolic solution containing 1 mmol UO₂(NO₃)₂·6H₂O was added 3 mmol of acetylacetone and 3 mmol of 1-phenyl-3-(pyridin-4-yl)propane in 5 ml MeOH. The solvent evaporated slowly at room temperature for a few days and orange crystal were obtained.

5. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2. All H atoms were placed at calculated positions [C(CH)—H = 0.93, C(CH₂)—H = 0.97 and C(CH₃)—H = 0.96Å] and allowed to ride on their parent atoms with U_iso(H) = 1.2U_eq(CH,CH₂) and U_iso(H) = 1.5U_eq(CH₃).

Table 2
Experimental details

Crystal data
Chemical formula	[UO₂(C₅H₇O₂)₂(C₁₄H₁₅N)]
M_r	665.51
Crystal system, space group	Triclinic, P $[\overline{1}]$
Temperature (K)	297
a, b, c (Å)	8.2100 (16), 11.530 (2), 14.516 (3)
α, β, γ (°)	108.67 (3), 98.50 (3), 100.81 (3)
V (Å³)	1246.4 (4)
Z	2
Radiation type	Mo Kα
μ (mm⁻¹)	6.55
Crystal size (mm)	0.47 × 0.29 × 0.26

Data collection
Diffractometer	Bruker SMART APEXII
Absorption correction	Analytical (XPREP; Bruker, 2007 )
T_min, T_max	0.149, 0.281
No. of measured, independent and observed [I > 2σ(I)] reflections	9353, 6948, 6026
R_int	0.015
(sin θ/λ)_max (Å⁻¹)	0.722

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.027, 0.056, 0.99
No. of reflections	6948
No. of parameters	293
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.88, −0.64
Computer programs: APEX2, SAINT and XSCANS (Bruker, 2007), SHELXS97, SHELXL97 and SHELXTL (Sheldrick, 2008 ), ORTEP-3 for Windows (Farrugia, 2012 ) and PLATON (Spek, 2009 ).

Supporting information

CCDC reference: 1037284

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S2056989014026607/cq2012sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989014026607/cq2012Isup2.hkl

checkCIF report

Computing details top

Data collection: APEX2 (Bruker, 2007) and XSCANS (Bruker, 2007); cell refinement: SAINT (Bruker, 2007) and XSCANS (Bruker, 2007); data reduction: APEX2 (Bruker, 2007) and SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008) and ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Dioxidobis(pentane-2,4-dionato-κ²O,O')[1-phenyl-3-(pyridin-4-yl)propane-κN]uranium(VI) top

Crystal data top

[U(C₅H₇O₂)₂O₂(C₁₄H₁₅N)]	Z = 2
M_r = 665.51	F(000) = 640
Triclinic, P1	D_x = 1.773 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 8.2100 (16) Å	Cell parameters from 4311 reflections
b = 11.530 (2) Å	θ = 2.6–28.5°
c = 14.516 (3) Å	µ = 6.55 mm⁻¹
α = 108.67 (3)°	T = 297 K
β = 98.50 (3)°	Block, orange
γ = 100.81 (3)°	0.47 × 0.29 × 0.26 mm
V = 1246.4 (4) Å³

Data collection top

Bruker SMART APEXII diffractometer	6948 independent reflections
Radiation source: fine-focus sealed tube	6026 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.015
Detector resolution: 8.333 pixels mm^-1	θ_max = 30.9°, θ_min = 1.9°
ω scans	h = −11→9
Absorption correction: analytical (XPREP; Bruker, 2007)	k = −16→15
T_min = 0.149, T_max = 0.281	l = −14→20
9353 measured reflections

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.027	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.056	H-atom parameters constrained
S = 0.99	w = 1/[σ²(F_o²) + (0.0257P)²] where P = (F_o² + 2F_c²)/3
6948 reflections	(Δ/σ)_max = 0.003
293 parameters	Δρ_max = 0.88 e Å⁻³
0 restraints	Δρ_min = −0.64 e Å⁻³

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 > 2σ(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
U1	0.488854 (15)	0.690915 (11)	0.372080 (8)	0.03519 (4)
O1	0.3391 (3)	0.5504 (2)	0.3581 (2)	0.0535 (6)
O2	0.6386 (3)	0.8327 (2)	0.38786 (19)	0.0525 (6)
O3	0.6977 (3)	0.6473 (3)	0.47398 (18)	0.0566 (7)
O4	0.6471 (3)	0.5741 (2)	0.27211 (18)	0.0521 (6)
O5	0.3569 (4)	0.6784 (3)	0.21310 (17)	0.0579 (7)
O6	0.2846 (3)	0.8105 (3)	0.38825 (18)	0.0567 (7)
N1	0.4613 (4)	0.7730 (3)	0.55740 (19)	0.0397 (6)
C1	0.9705 (6)	0.6794 (5)	0.5706 (3)	0.0810 (14)
H1A	0.9878	0.7680	0.6071	0.121*
H1B	1.0774	0.6618	0.5601	0.121*
H1C	0.9231	0.6316	0.6080	0.121*
C2	0.8488 (5)	0.6426 (3)	0.4705 (3)	0.0493 (9)
C3	0.9047 (5)	0.6043 (4)	0.3827 (3)	0.0573 (10)
H3	1.0188	0.6043	0.3872	0.069*
C4	0.8004 (5)	0.5661 (3)	0.2886 (3)	0.0497 (9)
C5	0.8646 (7)	0.5049 (5)	0.1981 (4)	0.0757 (14)
H5A	0.7867	0.4249	0.1584	0.114*
H5B	0.9744	0.4920	0.2186	0.114*
H5C	0.8738	0.5586	0.1595	0.114*
C6	0.2066 (7)	0.6847 (5)	0.0645 (3)	0.0796 (15)
H6A	0.3049	0.7172	0.0433	0.119*
H6B	0.1140	0.7170	0.0434	0.119*
H6C	0.1752	0.5940	0.0354	0.119*
C7	0.2466 (5)	0.7251 (4)	0.1764 (3)	0.0496 (9)
C8	0.1637 (5)	0.8067 (4)	0.2321 (3)	0.0560 (10)
H8	0.0878	0.8375	0.1980	0.067*
C9	0.1856 (4)	0.8459 (3)	0.3350 (3)	0.0473 (8)
C10	0.0891 (6)	0.9354 (4)	0.3879 (3)	0.0670 (12)
H10A	−0.0194	0.8881	0.3894	0.101*
H10B	0.0723	0.9919	0.3531	0.101*
H10C	0.1526	0.9833	0.4549	0.101*
C11	0.4545 (5)	0.6962 (3)	0.6101 (3)	0.0449 (8)
H11	0.4583	0.6129	0.5791	0.054*
C12	0.4422 (5)	0.7361 (4)	0.7083 (3)	0.0479 (8)
H12	0.4371	0.6798	0.7421	0.058*
C13	0.4373 (4)	0.8594 (3)	0.7568 (2)	0.0434 (8)
C14	0.4484 (5)	0.9381 (3)	0.7028 (3)	0.0476 (8)
H14	0.4501	1.0227	0.7333	0.057*
C15	0.4570 (5)	0.8929 (3)	0.6042 (3)	0.0470 (8)
H15	0.4599	0.9474	0.5688	0.056*
C16	0.4135 (6)	0.9028 (4)	0.8628 (3)	0.0576 (10)
H16A	0.4701	0.9919	0.8956	0.069*
H16B	0.4675	0.8568	0.8984	0.069*
C17	0.2268 (6)	0.8831 (4)	0.8692 (3)	0.0586 (10)
H17A	0.1655	0.7980	0.8253	0.070*
H17B	0.2195	0.8901	0.9367	0.070*
C18	0.1404 (5)	0.9765 (4)	0.8412 (3)	0.0536 (9)
H18A	0.1565	0.9747	0.7759	0.064*
H18B	0.0192	0.9492	0.8361	0.064*
C19	0.2056 (5)	1.1116 (4)	0.9144 (3)	0.0488 (8)
C20	0.1846 (6)	1.1420 (4)	1.0114 (3)	0.0621 (11)
H20	0.1317	1.0788	1.0318	0.075*
C21	0.2424 (6)	1.2672 (5)	1.0796 (3)	0.0750 (14)
H21	0.2255	1.2868	1.1442	0.090*
C22	0.3239 (6)	1.3604 (5)	1.0503 (4)	0.0772 (14)
H22	0.3654	1.4431	1.0952	0.093*
C23	0.3428 (7)	1.3292 (5)	0.9534 (4)	0.0796 (14)
H23	0.3952	1.3923	0.9328	0.096*
C24	0.2867 (6)	1.2082 (4)	0.8869 (3)	0.0627 (11)
H24	0.3030	1.1900	0.8222	0.075*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
U1	0.03593 (7)	0.03608 (7)	0.03601 (7)	0.01545 (5)	0.00830 (5)	0.01242 (5)
O1	0.0494 (15)	0.0444 (15)	0.0616 (16)	0.0058 (12)	0.0129 (12)	0.0154 (12)
O2	0.0563 (16)	0.0411 (14)	0.0611 (16)	0.0096 (12)	0.0197 (13)	0.0182 (12)
O3	0.0536 (16)	0.078 (2)	0.0503 (14)	0.0391 (15)	0.0132 (12)	0.0262 (14)
O4	0.0537 (16)	0.0575 (16)	0.0478 (14)	0.0285 (13)	0.0151 (12)	0.0124 (12)
O5	0.0669 (18)	0.0722 (19)	0.0417 (13)	0.0421 (15)	0.0081 (12)	0.0175 (13)
O6	0.0607 (17)	0.0762 (19)	0.0453 (13)	0.0456 (15)	0.0134 (12)	0.0208 (13)
N1	0.0469 (16)	0.0383 (15)	0.0385 (14)	0.0166 (13)	0.0148 (12)	0.0141 (12)
C1	0.067 (3)	0.093 (4)	0.075 (3)	0.026 (3)	−0.012 (2)	0.029 (3)
C2	0.046 (2)	0.043 (2)	0.062 (2)	0.0183 (16)	0.0049 (17)	0.0212 (17)
C3	0.0358 (19)	0.065 (3)	0.079 (3)	0.0201 (18)	0.0187 (19)	0.030 (2)
C4	0.052 (2)	0.044 (2)	0.068 (2)	0.0230 (17)	0.0303 (19)	0.0257 (18)
C5	0.093 (4)	0.072 (3)	0.086 (3)	0.043 (3)	0.054 (3)	0.032 (3)
C6	0.092 (4)	0.107 (4)	0.046 (2)	0.048 (3)	0.004 (2)	0.029 (2)
C7	0.048 (2)	0.056 (2)	0.0462 (19)	0.0167 (18)	0.0018 (16)	0.0232 (17)
C8	0.055 (2)	0.064 (3)	0.052 (2)	0.030 (2)	0.0006 (18)	0.0204 (19)
C9	0.0377 (18)	0.043 (2)	0.058 (2)	0.0173 (15)	0.0035 (16)	0.0130 (17)
C10	0.062 (3)	0.068 (3)	0.071 (3)	0.040 (2)	0.011 (2)	0.014 (2)
C11	0.057 (2)	0.0391 (19)	0.0473 (19)	0.0229 (16)	0.0172 (17)	0.0184 (15)
C12	0.060 (2)	0.049 (2)	0.0470 (19)	0.0214 (18)	0.0182 (17)	0.0262 (17)
C13	0.0427 (19)	0.048 (2)	0.0362 (16)	0.0154 (16)	0.0057 (14)	0.0101 (15)
C14	0.060 (2)	0.0379 (19)	0.0438 (18)	0.0158 (17)	0.0158 (17)	0.0096 (15)
C15	0.062 (2)	0.0379 (19)	0.0488 (19)	0.0157 (17)	0.0215 (17)	0.0192 (16)
C16	0.076 (3)	0.066 (3)	0.0361 (18)	0.034 (2)	0.0081 (18)	0.0178 (18)
C17	0.079 (3)	0.055 (2)	0.051 (2)	0.021 (2)	0.029 (2)	0.0227 (19)
C18	0.052 (2)	0.057 (2)	0.053 (2)	0.0113 (18)	0.0174 (18)	0.0191 (19)
C19	0.0391 (19)	0.058 (2)	0.048 (2)	0.0161 (17)	0.0076 (16)	0.0160 (18)
C20	0.063 (3)	0.065 (3)	0.056 (2)	0.015 (2)	0.018 (2)	0.017 (2)
C21	0.073 (3)	0.084 (4)	0.058 (3)	0.033 (3)	0.011 (2)	0.007 (2)
C22	0.069 (3)	0.051 (3)	0.094 (4)	0.018 (2)	−0.001 (3)	0.009 (3)
C23	0.081 (3)	0.053 (3)	0.103 (4)	0.013 (2)	0.019 (3)	0.029 (3)
C24	0.064 (3)	0.063 (3)	0.069 (3)	0.021 (2)	0.019 (2)	0.030 (2)

Geometric parameters (Å, º) top

U1—O1	1.773 (3)	C10—H10A	0.9600
U1—O2	1.777 (3)	C10—H10B	0.9600
U1—O3	2.330 (2)	C10—H10C	0.9600
U1—O4	2.360 (2)	C11—C12	1.376 (5)
U1—O5	2.348 (2)	C11—H11	0.9300
U1—O6	2.354 (2)	C12—C13	1.382 (5)
U1—N1	2.610 (3)	C12—H12	0.9300
O3—C2	1.260 (4)	C13—C14	1.375 (5)
O4—C4	1.272 (4)	C13—C16	1.512 (5)
O5—C7	1.271 (4)	C14—C15	1.375 (5)
O6—C9	1.251 (4)	C14—H14	0.9300
N1—C11	1.342 (4)	C15—H15	0.9300
N1—C15	1.342 (4)	C16—C17	1.528 (6)
C1—C2	1.519 (5)	C16—H16A	0.9700
C1—H1A	0.9600	C16—H16B	0.9700
C1—H1B	0.9600	C17—C18	1.519 (5)
C1—H1C	0.9600	C17—H17A	0.9700
C2—C3	1.384 (6)	C17—H17B	0.9700
C3—C4	1.386 (6)	C18—C19	1.517 (6)
C3—H3	0.9300	C18—H18A	0.9700
C4—C5	1.501 (5)	C18—H18B	0.9700
C5—H5A	0.9600	C19—C20	1.382 (5)
C5—H5B	0.9600	C19—C24	1.389 (6)
C5—H5C	0.9600	C20—C21	1.407 (6)
C6—C7	1.505 (5)	C20—H20	0.9300
C6—H6A	0.9600	C21—C22	1.375 (7)
C6—H6B	0.9600	C21—H21	0.9300
C6—H6C	0.9600	C22—C23	1.375 (7)
C7—C8	1.385 (5)	C22—H22	0.9300
C8—C9	1.388 (5)	C23—C24	1.362 (6)
C8—H8	0.9300	C23—H23	0.9300
C9—C10	1.504 (5)	C24—H24	0.9300

O1—U1—O2	179.19 (11)	O6—C9—C8	122.9 (3)
O1—U1—O3	91.86 (12)	O6—C9—C10	116.8 (3)
O1—U1—O4	91.38 (11)	C8—C9—C10	120.3 (3)
O1—U1—O5	89.82 (12)	C9—C10—H10A	109.5
O1—U1—O6	92.85 (12)	C9—C10—H10B	109.5
O2—U1—O3	87.91 (12)	H10A—C10—H10B	109.5
O2—U1—O4	89.27 (11)	C9—C10—H10C	109.5
O2—U1—O5	90.77 (12)	H10A—C10—H10C	109.5
O2—U1—O6	86.82 (11)	H10B—C10—H10C	109.5
O3—U1—O4	70.88 (9)	N1—C11—C12	122.5 (3)
O3—U1—O5	149.99 (9)	N1—C11—H11	118.8
O3—U1—O6	138.83 (9)	C12—C11—H11	118.8
O4—U1—O5	79.13 (9)	C11—C12—C13	120.3 (3)
O4—U1—O6	149.71 (9)	C11—C12—H12	119.8
O5—U1—O6	70.91 (9)	C13—C12—H12	119.8
O1—U1—N1	86.45 (11)	C14—C13—C12	116.7 (3)
O2—U1—N1	92.74 (11)	C14—C13—C16	122.3 (3)
O3—U1—N1	69.37 (9)	C12—C13—C16	121.0 (3)
O4—U1—N1	140.08 (8)	C15—C14—C13	120.7 (3)
O5—U1—N1	140.62 (9)	C15—C14—H14	119.6
O6—U1—N1	70.15 (9)	C13—C14—H14	119.6
C2—O3—U1	132.2 (2)	N1—C15—C14	122.3 (3)
C4—O4—U1	132.7 (2)	N1—C15—H15	118.9
C7—O5—U1	137.4 (2)	C14—C15—H15	118.9
C9—O6—U1	139.2 (2)	C13—C16—C17	113.2 (3)
C11—N1—C15	117.5 (3)	C13—C16—H16A	108.9
C11—N1—U1	120.6 (2)	C17—C16—H16A	108.9
C15—N1—U1	121.9 (2)	C13—C16—H16B	108.9
C2—C1—H1A	109.5	C17—C16—H16B	108.9
C2—C1—H1B	109.5	H16A—C16—H16B	107.7
H1A—C1—H1B	109.5	C18—C17—C16	113.9 (3)
C2—C1—H1C	109.5	C18—C17—H17A	108.8
H1A—C1—H1C	109.5	C16—C17—H17A	108.8
H1B—C1—H1C	109.5	C18—C17—H17B	108.8
O3—C2—C3	123.9 (4)	C16—C17—H17B	108.8
O3—C2—C1	115.6 (4)	H17A—C17—H17B	107.7
C3—C2—C1	120.5 (4)	C19—C18—C17	114.2 (3)
C2—C3—C4	123.8 (3)	C19—C18—H18A	108.7
C2—C3—H3	118.1	C17—C18—H18A	108.7
C4—C3—H3	118.1	C19—C18—H18B	108.7
O4—C4—C3	124.5 (3)	C17—C18—H18B	108.7
O4—C4—C5	115.8 (4)	H18A—C18—H18B	107.6
C3—C4—C5	119.7 (4)	C20—C19—C24	117.9 (4)
C4—C5—H5A	109.5	C20—C19—C18	120.4 (4)
C4—C5—H5B	109.5	C24—C19—C18	121.7 (4)
H5A—C5—H5B	109.5	C19—C20—C21	120.9 (4)
C4—C5—H5C	109.5	C19—C20—H20	119.5
H5A—C5—H5C	109.5	C21—C20—H20	119.5
H5B—C5—H5C	109.5	C22—C21—C20	119.7 (5)
C7—C6—H6A	109.5	C22—C21—H21	120.1
C7—C6—H6B	109.5	C20—C21—H21	120.1
H6A—C6—H6B	109.5	C21—C22—C23	118.8 (5)
C7—C6—H6C	109.5	C21—C22—H22	120.6
H6A—C6—H6C	109.5	C23—C22—H22	120.6
H6B—C6—H6C	109.5	C24—C23—C22	121.7 (5)
O5—C7—C8	124.5 (3)	C24—C23—H23	119.1
O5—C7—C6	115.5 (4)	C22—C23—H23	119.1
C8—C7—C6	120.0 (3)	C23—C24—C19	120.8 (4)
C7—C8—C9	124.8 (3)	C23—C24—H24	119.6
C7—C8—H8	117.6	C19—C24—H24	119.6
C9—C8—H8	117.6

Acknowledgements

This work was supported by a MEXT (Ministry of Education, Culture, Sports, Science and Technology, Japan)-Supported Program for the Strategic Research Foundation at Private Universities 2012–2016.

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