Synthesis, crystal structure and photophysical properties of 1,4-bis(1,3-diazaazulen-2-yl)benzene: A new π building block.

Article abstract of DOI:10.1107/S2053229617018459

A dimerized 1,3-diazaazulene derivative, namely 1,4-bis(1,3-diazaazulen-2-yl)benzene [or 2,2′-(1,4-phenylene)bis(1,3-diazaazulene)], C₂₂H₁₄N₄, (I), has been synthesized successfully through the condensation reaction betwee

Full text of DOI:10.1107/S2053229617018459

research papers
Synthesis, crystal structure and photophysical
properties of 1,4-bis(1,3-diazaazulen-2-yl)benzene:
a new p building block
ISSN 2053-2296
Peili Sun, Zongyao Zhang, Hongxia Luo, Pu Zhang,* Yujun Qin and Zhi-Xin Guo*
Department of Chemistry, Renmin University of China, Zhongguancun Street, Beijing 100872, People’s Republic of
China. *Correspondence e-mail: zhangpu@ruc.edu.cn, gzhixin@ruc.edu.cn
Received 1 November 2017
Accepted 27 December 2017
A dimerized 1,3-diazaazulene derivative, namely 1,4-bis(1,3-diazaazulen-2-yl)-
benzene [or 2,20-(1,4-phenylene)bis(1,3-diazaazulene)], C22H14N4, (I), has been
synthesized successfully through the condensation reaction between 2-methoxy-
tropone and benzene-1,4-dicarboximidamide hydrochloride, and was character-
Edited by T.-B. Lu, Sun Yat-Sen University,
People’s Republic of China
Keywords: 1,3-diazaazulene; ꢀ building block;
DFT calculations; computational chemistry;
nonlinear optical material; crystal structure;
organic functional materials; photophysical
properties.
1
ized by H NMR and 13C NMR spectroscopies, and ESI–MS. X-ray diffraction
analysis reveals that (I) has a nearly planar structure with good ꢀ-electron
delocalization, indicating that it might serve as a ꢀ building block. The crystal
belongs to the monoclinic system. One-dimensional chains were formed along
the a axis through ꢀ–ꢀ interactions and adjacent chains are stabilized by C—
Hꢀ ꢀ ꢀN interactions, forming a three-dimensional architecture. The solid
emission of (I) in the crystalline form exhibited a 170 nm red shift compared
with that in the solution state. The observed optical bandgap for (I) is 3.22 eV
and a cyclic voltammetry experiment confirmed the energy levels of the highest
occupied molecular orbital (HOMO) and the lowest unoccupied molecular
orbital (LUMO). The calculated bandgap for (I) is 3.37 eV, which is very close to
the experimental result. In addition, the polarizability and hyperpolarizability of
(I) were appraised for its further application in second-order nonlinear optical
materials.
CCDC reference: 1813489
Supporting information: this article has
supporting information at journals.iucr.org/c
1. Introduction
Organic functional materials have attracted much attention
due to their potential applications in optoelectronics (Ostro-
¨
verkhova, 2016; Gsanger et al., 2016), semiconducting devices
(Gsanger et al., 2016) and chemical sensors (Bansal et al.,
¨
2015). Aromatic conjugated skeletons are interesting since
they serve as building blocks for organic functional materials
(Zhang et al., 2013; Jiang et al., 2009). For example, azulene
derivatives were reported to display tunable photophysical
and optical behaviours and are candidates for optical mate-
rials owing to their unique polarized charge distribution on the
fused seven- and five-membered rings (Xin et al., 2016; Tsurui
et al., 2014).
Within many reported structures related to azulene, 1,3-
diazaazulene is a unique derivative in which two C atoms are
replaced by N atoms, with a rather large dipole moment
located within the heteroaromatic core (Braun et al., 1973;
Nozoe et al., 1954). Studies show that 1,3-diazaazulene deri-
vatives display promising performance in liquid crystal (Mori
# 2018 International Union of Crystallography
Acta Cryst. (2018). C74, 171–176
https://doi.org/10.1107/S2053229617018459 171

research papers
Table 1
Experimental details.
et al., 2003) and nonlinear optical materials (Ma et al., 2011;
Zhu et al., 2007). As was reported, molecules with more N
atoms in the conjugated system offer more possibilities for
modulating stability, photophysical and electronic properties,
and the generation of various structural backbones, and might
display better photochemical stability and diverse properties
(Zhou et al., 2016; Liang et al., 2011; Winkler & Houk, 2007).
Thus, 1,3-diazaazulene is an interesting fragment for the
construction of new ꢀ building blocks for organic optoelec-
tronic materials.
In our previously published 1,3-diazaazulene derivatives,
which have one 1,3-diazaazulene ring bonded to the arene
ring, the rings are coplanar, forming a 16-ꢀ-electron conju-
gated structure (Rao et al., 2017; Ma et al., 2011; Zhu et al.,
2007). Hence, it can be deduced that it is possible to design
conjugated molecules containing more N atoms by introdu-
cing further 1,3-diazaazulene groups to the arene ring.
We designed a dimerized 1,3-diazaazulene derivative,
namely 1,4-bis(1,3-diazaazulen-2-yl)benzene, (I) (Scheme 1),
with two 1,3-diazaazulene units connected through an arene
bridge, which presents a larger conjugated system together
with an increased number of N atoms. We report the synthesis
and single-crystal X-ray structure characterization of (I), as
well as an analysis of its photophysical and electrochemical
properties. Theoretical calculations were also carried out to
support the experimental studies.
Crystal data
Chemical formula
Mr
Crystal system, space group
Temperature (K)
˚
a, b, c (A)
C22H14N4
334.37
Monoclinic, P21/n
106
3.7610 (3), 13.2538 (9),
18.8657 (19)
91.226 (9)
940.19 (14)
2
Mo Kꢃ
0.07
0.40 ꢄ 0.06 ꢄ 0.03
ꢂ (ꢂ)
3
˚
V (A )
Z
Radiation type
ꢄ (mmꢃ1
Crystal size (mm)
)
Data collection
Diffractometer
Absorption correction
Agilent Xcalibur Eos Gemini
Multi-scan (CrysAlis PRO;
Agilent, 2011)
0.974, 1.000
3520, 1846, 1396
Tmin, Tmax
No. of measured, independent and
observed [I > 2ꢅ(I)] reflections
Rint
0.030
0.617
ꢃ1
˚
(sin ꢆ/ꢇ)max (A
)
Refinement
R[F2 > 2ꢅ(F2)], wR(F2), S
No. of reflections
No. of parameters
0.054, 0.155, 1.06
1846
118
H atoms treated by a mixture of
independent and constrained
refinement
H-atom treatment
ꢃ3
˚
Áꢈmax, Áꢈmin (e A
)
0.20, ꢃ0.20
Computer programs: CrysAlis PRO (Agilent, 2011), SHELXS97 (Sheldrick, 2008),
SHELXL97 (Sheldrick, 2008) and OLEX2 (Dolomanov et al., 2009).
analysis calculated (%): C 79.02, H 4.22, N 16.76; found: C
79.2, H 4.0, N 16.3; the absolute errors are 0.18% for C, 0.22%
for H and 0.34% for N.
It should be noted that the solvent used for the condensa-
tion reaction should be methanol, not ethanol, since the use of
ethanol would mostly convert 2-methoxytropone to 2-ethoxy-
tropone and (I) would not be obtained. The preparation of
benzene-1,4-dicarboximidamide hydrochloride, i.e. (4), and
2. Experimental
2.1. Synthesis and crystallization
For the preparation of target compound (I), t-BuOK
(191 mg, 4.0 equiv.) was added to a methanol solution of
benzene-1,4-dicarboximidamide hydrochloride (100 mg,
1.0 equiv.), as shown in Scheme 2. The mixture was stirred for
30 min and cooled in an ice bath. A methanol solution of
2-methoxytropone (173 mg, 3.0 equiv.) was added carefully
dropwise. The resulting solution was heated under reflux and
the reaction was monitored by thin-layer chromatography
(RF = 0.1, MeOH/CH2Cl2 = 1:10 v/v). A light-yellow powder
was obtained by flash-column chromatography with CH3OH/
1
CH2Cl2 (1:50 v/v) as eluent. H NMR (400 MHz, CDCl3): ꢁ
8.79–8.73 (m, 4H), 8.63 (s, 4H), 8.08 (d, J = 7.8 Hz, 6H); 13C
NMR (101 MHz, CDCl3): ꢁ 174.60, 162.95, 162.46, 139.03,
135.18, 134.87, 129.56; HRMS (ESI): m/z [M]+ calculated for
[C22H14N4 + H+] 335.12912; found 335.12826. Elemental
Figure 1
Thermogravimetric analysis of (I). The heating rate was 10 K minꢃ1
under an N2 flow.
ꢁ
172 Sun et al. 1,4-Bis(1,3-diazaazulen-2-yl)benzene
Acta Cryst. (2018). C74, 171–176

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2-methoxytropone, (2), are described in the supporting
information, as are their specific characterizations.
The lifetimes of (I) in dichloromethane solution (1 ꢄ
10ꢃ5 mol lꢃ1) and in the crystalline state were investigated on
an UltraFast lifetime Spectrofluorometer (Delta flex).
Yellow needle-shaped crystals of (I) suitable for single-
crystal X-ray analysis were grown via slow evaporation from a
mixed solvent of dichloromethane and methanol (3:1 v/v) at
room temperature for 3 d. Elemental analysis (vario EL
elemental analyser) and themogravimetric differential scan-
ning calorimetry (SDT Q600 analyser, under a nitrogen flow,
10 K minꢃ1) investigations were carried out to determine the
amount of solvent in the crystal. Powder X-ray diffraction
studies were also carried out (Shimadzu XRD-7000) with
Cu Kꢃ radiation to analyse the phase purity of the bulk sample
of (I).
2.5. Electrochemical study
The electrochemical properties of (I) in acetonitrile
(CH3CN) were studied on a CHI 660D workstation (CH
Instruments Inc., China) with tetrabutylammonium hexa-
fluorophosphate (Bu4NPF6) (0.1 mol lꢃ1) as electrolyte. A
traditional three-electrode system, consisting of a bare GC
(È = 3.0 mm) working electrode, an Ag/AgCl (in 3.0 mol lꢃ1
KCl) reference electrode and a platinum wire auxiliary elec-
trode, was used. The scan rate was 100 mV sꢃ1
.
2.2. Refinement
3. Results and discussion
Crystal data, data collection and structure refinement
details are summarized in Table 1. C-bound H atoms were
placed in calculated positions and treated using a riding-model
3.1. Synthesis and characterization
Compound (I) was obtained in good yield as a pale-yellow
powder through the condensation reaction of one equivalent
of benzene-1,4-dicarboximidamide hydrochloride and three
equivalents of 2-methoxytropone. The chemical structure was
identified by 1H NMR and 13C NMR spectroscopies, and ESI–
MS (see supporting information). Compound (I) exhibits a
low solubility in most solvents, except dichloromethane,
chloroform and methanol, due to its expanded ꢀ-conjugated
structure with no hydrophilic substitutions.
The elemental analysis results (see x2.1) are well within the
margin of error, suggesting that almost no solvent molecules
exist in the crystal. Thermogravimetric analysis (TGA) shows
that there is a weight loss of only 0.8% below 473 K,
confirming the presence of little or no solvent in the crystal
(Fig. 1). From the powder X-ray diffraction (PXRD) results,
we found that the patterns matched with the simulated results
very well, confirming the phase purity of the bulk sample used
for the other measurements (Fig. 2).
˚
approximation, with C—H = 0.93 A, and refined as riding,
with Uiso(H) = 1.2Ueq(C). A region of electron density was
removed using the SQUEEZE (Spek, 2015) procedure in
PLATON (Spek, 2009). SQUEEZE calculated two voids with
a volume of approximately 96 A occupied by 16 electrons per
unit cell.
3
˚
2.3. Computational methods
The crystal structure parameters of (I) were used in the
calculations without any optimization. All calculations were
performed using GAUSSIAN09 software (Revision A.02;
Frisch et al., 2009). Density functional theory (DFT) calcula-
tions were carried out at the B3LYP/6-311G(d,p) level for the
gas state. The polarizability, the first hyperpolarizability tensor
components, the highest occupied molecular orbital (HOMO)
and the lowest occupied molecular orbital (LUMO) were all
displayed based on the crystal structure parameters without
any optimization, and details are presented in the supporting
information.
2.4. UV–Vis absorption and fluorescence studies
The general photophysical properties of (I) in solution were
characterized in dichloromethane, including the UV–Vis
absorption (8 ꢄ 10ꢃ5 mol lꢃ1) and fluorescence excitation/
emission (1 ꢄ 10ꢃ5 mol lꢃ1) spectra. The UV–Vis absorption
spectrum was recorded on a Varian Cary 50 UV–Vis spec-
trophotometer and the fluorescence spectra were recorded on
an FLS980 steady-state and time-resolved fluorescence spec-
trophotometer.
The solid-state photophysical properties of (I) were also
studied. The UV–Vis absorption spectrum was recorded on a
Shimazu UV3600Plus UV–Vis–NIR (NIR is near IR) spec-
trophotometer equipped with an integrating sphere. The
fluorescence emission spectrum was recorded on an FLS980
steady-state and time-resolved fluorescence spectrophotom-
eter.
Figure 2
Comparison of the experimental PXRD pattern (red line) with the
simulated pattern from the single-crystal structure (black line) for
compound (I).
ꢁ
Acta Cryst. (2018). C74, 171–176
Sun et al.
1,4-Bis(1,3-diazaazulen-2-yl)benzene 173

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Table 2
Selected geometric parameters (A, ).
ꢂ
˚
N2—C1
N2—C6
N1—C1
N1—C5
C2—C1
C2—C4
C2—C3
C4—C3i
1.353 (3)
1.354 (3)
1.359 (3)
1.360 (3)
1.468 (3)
1.403 (3)
1.399 (3)
1.393 (3)
C7—C8
C7—C6
C8—C9
C5—C6
C5—C11
C10—C11
C10—C9
1.393 (3)
1.393 (3)
1.387 (3)
1.462 (3)
1.397 (3)
1.390 (3)
1.393 (3)
C4—C2—C1—N2
C4—C2—C1—N1
12.0 (3)
ꢃ167.08 (18)
C3—C2—C1—N2
C3—C2—C1—N1
ꢃ169.12 (17)
11.8 (3)
Symmetry code: (i) ꢃx þ 1; ꢃy þ 1; ꢃz.
3.2. Crystal structure of compound (I)
Short and straight golden needle-shaped crystals of (I) were
obtained. The molecular structure is shown in Fig. 3(a).
Selected geometric parameters are presented in Table 2. The
single-crystal X-ray results indicate that (I) crystallizes in the
monoclinic system (space group P21/n) (Fig. 3a) and that the
unit cell consists of two molecules (Fig. 3b). The molecular
structure of (I) shows that the two diazaazulene rings are
coplanar, but there is a torsion angle of 11.8 (3)ꢂ (C3—C2—
C1—N1; Table 2) between the diazaazulene and arene rings.
This value is larger than that of the anologue previously
reported by our group, namely 2-(4-aminophenyl)-6-nitro-1,3-
diazaazulene (Ma et al., 2011), whose twist is only 1.1ꢂ between
the diazaazulene and arene rings. Thus, the connection of two
diazaazulene rings to the arene ring led to an increase of the
Figure 4
Crystal packing diagrams of (I), showing (a) chains formed through ꢀ–ꢀ
interactions along the a axis and (b) the three-dimensional architecture
(the grey dashed lines represent weak C—Hꢀ ꢀ ꢀN interactions).
dihedral angle between the conjugated rings in the crystal
structure. In addition, the C—C bond lengths range from
˚
1.387 (3) to 1.468 (3) A (Table 2), falling in the range of typical
˚
˚
C—C single (1.54 A) and C—C aryl bonds (1.36 A), and the
˚
C—N bond lengths range from 1.353 (3) to 1.360 (3) A
˚
(Table 2), falling in the range of typical C—N single (1.47 A)
˚
and double bonds (1.27 A) (Zarei et al., 2017). These obser-
vations indicate good ꢀ-electron delocalization across the
molecule of (I). In the crystal packing structure, one-dimen-
sional chains are formed along the a axis through ꢀ–ꢀ inter-
˚
actions, with a centroid–centroid distance of 3.761 (1) A and a
˚
centroid–plane distance of 3.465 (1) A (Fig. 4a). Adjacent
chains were stabilized by weak C—Hꢀ ꢀ ꢀN interactions
˚
(Nobukuni et al., 2007), with a Cꢀ ꢀ ꢀN distance of 3.548 (?) A,
forming a three-dimensional architecture (Fig. 4b). The well-
organized stacking performance of (I) through intermolecular
interactions makes (I) promising as a ꢀ building block.
Figure 3
(a) The molecular structure of (I). Displacement ellipsoids are drawn at
the 50% probability level and H atoms are shown as small spheres of
arbitrary radii. (b) The unit cell (colour key: C atoms dark grey, N atoms
blue and H atoms light grey). [Symmetry code: (i) ꢃx + 1, ꢃy + 1, ꢃz.]
3.3. Photophysical properties
To illuminate the optical properties, the UV–Vis absorption
and fluorescence spectra of (I) are shown in Fig. 5. Compound
ꢁ
174 Sun et al. 1,4-Bis(1,3-diazaazulen-2-yl)benzene
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Table 3
Summary of the energy properties of (I).
red
1/2
E
LUMO
(eV)b
HOMO
(eV)c
Egap/ꢇmax
LUMO
(eV)e
HOMO
(eV)e
Egap
(eV)e
(V)a
[(eV)d/nm]
ꢃ1.67
ꢃ2.73
ꢃ5.95
3.22/385
ꢃ2.85
ꢃ6.02
3.37
Notes: (a) obtained from cyclic voltammograms; (b) calculated from cyclic voltammo-
grams; (c) calculated according to the formula EHOMO = ELUMO – Egap; (d) optical
bandgap, Egap = 1240/ꢇmax; (e) obtained from theoretical calculations.
(I) exhibited a main absorption peak at 385 nm with a
shoulder at 405 nm in dichloromethane. In the crystal, (I)
exhibited a broader absorption coverage ranging from 200 to
800 nm (Fig. 5a) due to the intermolecular interactions in the
crystalline state. Absorption spectra were also recorded in
other solvents with different polarities, and no obvious peak-
shape changes were observed, except for a slight red shift of
the maximum absorption peak with decreasing solvent
polarity (Fig. 1S of the supporting information). This is in good
agreement with the results reported for 1,3-diazaazulene
(Jinguji et al., 1985), indicating that the dipole moment of the
ground state (ꢄg) is larger than that of the excited state (ꢄe)
for (I) and that the ground state is difficult to polarize.
Figure 6
Cyclic voltammetry curve of (I) in acetonitrile.
of 95 nm, which is larger than for reported molecules with only
one 1,3-diazaazulene component (Ma et al., 2011). However,
the emission peak of (I) in the crystal is red shifted by 170 nm
compared with that in solution, with a value of 650 nm; the
peak shapes are similar. Results of lifetime studies show that
(I) in dichloromethane solution displays a shorter lifetime of
1.03 ns, while (I) in the crystal displays an average lifetime of
1.89 ns (see Fig. 2S in the supporting information). This might
be caused by the restricted motional freedom for (I) in the
crystal (Chosrowjan et al., 2007).
The fluorescence emission spectrum of (I) in solution
indicates a main S1!S0 emission at 480 nm, with a Stokes shift
3.4. Electrochemical properties
As shown in Fig. 6, (I) displays a pair of reduction/re-
oxidation peaks under negative voltage. When the potential
scan moved towards positive voltage, no oxidation peak was
observed. Therefore, (I) should be an inherent n-type organic
semiconductor. The half-wave reduction potential for (I) is
ꢃ1.67 V, in agreement with the LUMO energy level of
ꢃ2.73 V, obtained according to the empirical equation
ELUMO = ꢃ[4.4 + Ered] eV (Hong et al., 2011). The optical
bandgap was obtained based on the wavelength of the
observed maximum absorption peak. The HOMO energy
level could then be calculated from the optical bandgap and
the LUMO level, as shown in Table 3.
3.5. Calculation results
The theoretically calculated HOMO and LUMO energies
were analyzed based on the crystal structure parameters
(Fig. 3S and Table 1S of the supporting information). Data are
listed in Table 3 and compared with the experimental elec-
trochemical results. As can be seen, the calculated HOMO and
LUMO energies are very close to the observed results and the
calculated energy gap was 3.37 eV, in good agreement with the
experimental data (3.22 eV), with a small difference of
0.15 eV. In addition, the polarizability and hyperpolarizability
parameters of (I) are gathered in Table 2S of the supporting
information according to the x, y and z components defined by
Zarei et al.. (2017). However, (I) exhibited no nonlinear
optical (NLO) properties due to its centrosymmetric nature.
Figure 5
Normalized (a) absorption spectra and (b) fluorescence emission spectra
of (I) in dichloromethane solution (black) and in the crystalline state
(red).
ꢁ
Acta Cryst. (2018). C74, 171–176
Sun et al.
1,4-Bis(1,3-diazaazulen-2-yl)benzene 175

research papers
Dolomanov, O. V., Bourhis, L. J., Gildea, R. J., Howard, J. A. K. &
Puschmann, H. (2009). J. Appl. Cryst. 42, 339–341.
Frisch, M. J., et al. (2009). GAUSSIAN09. Gaussian Inc., Wallingford,
CT, USA. http://www.gaussian.com.
4. Conclusion
In summary, 1,4-bis(1,3-diazaazulen-2-yl)benzene, (I), a novel
chromophore based on 1,3-diazaazulene, was synthesized
successfully in excellent yield using methanol as solvent. To
the best of our knowledge, this is the first case where the
synthesis and crystal structure of dimerized 1,3-diazaazulene
have been discussed. Single-crystal X-ray diffraction results
show that (I) is a centrosymmetric molecule, with the atoms
arranged almost in a plane and forming a conjugation struc-
ture with 26-ꢀ electrons; it could thus serve as a ꢀ building
block. One-dimensional chains are formed based on inter-
molecular ꢀ–ꢀ interactions and adjacent chains are stabilized
by C—Hꢀ ꢀ ꢀN interactions, forming a well-organized three-
dimensional architecture. In addition, the calculated HOMO,
LUMO and bandgaps for (I) are very close to the experi-
mental electrochemical results. Even though the first hyper-
polarizability was zero due to its centrosymmetric
characteristic according our calculations, it is believed that a
good nonlinear optic performance could be expected if elec-
tron-donor/acceptor substituents were introduced to this
novel ꢀ-conjugation backbone.
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Funding information
Funding for this research was provided by: National Natural
Science Foundation of China (grant No. 21575160); Research
Funds of Renmin University of China (grant No. 15XNLQ04).
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176 Sun et al. 1,4-Bis(1,3-diazaazulen-2-yl)benzene
Acta Cryst. (2018). C74, 171–176

supporting information
supporting information
Acta Cryst. (2018). C74, 171-176 [https://doi.org/10.1107/S2053229617018459]
Synthesis, crystal structure and photophysical properties of 1,4-bis(1,3-diaza-
azulen-2-yl)benzene: a new π building block
Peili Sun, Zongyao Zhang, Hongxia Luo, Pu Zhang, Yujun Qin and Zhi-Xin Guo
Computing details
Data collection: CrysAlis PRO (Agilent, 2011); cell refinement: CrysAlis PRO (Agilent, 2011); data reduction: CrysAlis
PRO (Agilent, 2011); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine
structure: SHELXL97 (Sheldrick, 2008); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare
material for publication: OLEX2 (Dolomanov et al., 2009).
2-[4-(Cyclohepta[d]imidazol-2-yl)phenyl]cyclohepta[d]imidazole
Crystal data
C22H14N4
Mr = 334.37
F(000) = 348
Dx = 1.181 Mg m−3
Mo Kα radiation, λ = 0.7107 Å
Cell parameters from 868 reflections
θ = 3.2–29.1°
Monoclinic, P21/n
a = 3.7610 (3) Å
b = 13.2538 (9) Å
c = 18.8657 (19) Å
β = 91.226 (9)°
V = 940.19 (14) Å3
Z = 2
µ = 0.07 mm−1
T = 106 K
Needle, yellow
0.40 × 0.06 × 0.03 mm
Data collection
Agilent Xcalibur Eos Gemini
diffractometer
Radiation source: Enhance (Mo) X-ray Source
Graphite monochromator
Detector resolution: 16.0971 pixels mm-1
ω scans
3520 measured reflections
1846 independent reflections
1396 reflections with I > 2σ(I)
Rint = 0.030
θmax = 26.0°, θmin = 3.3°
h = −4→4
k = −16→9
l = −23→23
Absorption correction: multi-scan
(CrysAlis PRO; Agilent, 2011)
T
min = 0.974, Tmax = 1.000
Refinement
Refinement on F2
Least-squares matrix: full
R[F2 > 2σ(F2)] = 0.054
wR(F2) = 0.155
S = 1.06
1846 reflections
118 parameters
0 restraints
Primary atom site location: structure-invariant
direct methods
Secondary atom site location: difference Fourier
map
Hydrogen site location: inferred from
neighbouring sites
H atoms treated by a mixture of independent
and constrained refinement
Acta Cryst. (2018). C74, 171-176
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supporting information
w = 1/[σ2(Fo2) + (0.0762P)2 + 0.1696P]
where P = (Fo2 + 2Fc2)/3
(Δ/σ)max < 0.001
Δρmax = 0.20 e Å−3
Δρmin = −0.20 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.
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 > σ(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)
x
y
z
Uiso*/Ueq
N2
N1
C2
C1
C4
H4
C3
H3
C7
H7
C8
H8
C5
0.1546 (4)
0.2047 (4)
0.3804 (5)
0.2471 (5)
0.3503 (5)
0.2500
0.5311 (5)
0.5522
−0.0754 (5)
−0.0712
−0.1973 (5)
−0.2623
0.0698 (5)
0.0408 (5)
−0.1619 (5)
−0.2142
−0.0212 (5)
0.0165
−0.2352 (5)
−0.3238
0.52343 (13)
0.68447 (13)
0.54193 (16)
0.58368 (16)
0.43798 (16)
0.3965
0.60383 (15)
0.6729
0.55841 (17)
0.4894
0.61972 (18)
0.5862
0.69108 (16)
0.58873 (16)
0.79588 (17)
0.8622
0.78228 (17)
0.8404
0.72377 (18)
0.7495
0.18448 (8)
0.13999 (9)
0.06353 (10)
0.12997 (10)
0.05077 (10)
0.0847
0.01219 (10)
0.0201
0.30062 (11)
0.3096
0.35492 (12)
0.3960
0.20612 (11)
0.23432 (10)
0.30496 (11)
0.3171
0.23809 (11)
0.2117
0.35631 (11)
0.3983
0.0228 (4)
0.0218 (4)
0.0194 (5)
0.0199 (5)
0.0202 (5)
0.024*
0.0206 (5)
0.025*
0.0288 (5)
0.035*
0.0293 (5)
0.035*
0.0218 (5)
0.0220 (5)
0.0285 (5)
0.034*
0.0261 (5)
0.031*
0.0289 (5)
0.035*
C6
C10
H10
C11
H11
C9
H9
Atomic displacement parameters (Å2)
U11
U22
U33
U12
U13
U23
N2
N1
C2
C1
C4
C3
C7
C8
0.0260 (9)
0.0227 (8)
0.0156 (9)
0.0165 (9)
0.0189 (9)
0.0200 (9)
0.0334 (11)
0.0300 (11)
0.0237 (9)
0.0240 (9)
0.0254 (11)
0.0245 (10)
0.0244 (11)
0.0202 (10)
0.0285 (12)
0.0368 (13)
0.0190 (9)
0.0004 (7)
0.0019 (7)
0.0012 (8)
−0.0008 (8)
0.0001 (8)
0.0016 (8)
−0.0039 (9)
−0.0048 (10)
0.0034 (7)
0.0006 (7)
−0.0021 (7)
−0.0019 (7)
0.0002 (8)
−0.0012 (8)
0.0037 (9)
0.0066 (9)
−0.0031 (7)
−0.0017 (7)
−0.0007 (8)
−0.0015 (8)
0.0005 (9)
−0.0008 (8)
−0.0016 (10)
−0.0045 (10)
0.0187 (8)
0.0170 (10)
0.0187 (10)
0.0174 (9)
0.0214 (10)
0.0248 (11)
0.0215 (11)
Acta Cryst. (2018). C74, 171-176
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supporting information
C5
C6
C10
C11
C9
0.0180 (9)
0.0215 (9)
0.0262 (10)
0.0266 (10)
0.0264 (10)
0.0269 (11)
0.0248 (10)
0.0301 (12)
0.0242 (10)
0.0393 (13)
0.0202 (10)
0.0198 (10)
0.0290 (12)
0.0276 (11)
0.0212 (11)
−0.0007 (8)
−0.0014 (8)
0.0048 (9)
0.0025 (9)
0.0020 (10)
−0.0023 (8)
−0.0006 (8)
−0.0023 (9)
−0.0009 (9)
0.0009 (9)
−0.0026 (9)
−0.0038 (9)
−0.0119 (10)
−0.0034 (9)
−0.0114 (10)
Geometric parameters (Å, º)
N2—C1
N2—C6
N1—C1
N1—C5
C2—C1
C2—C4
C2—C3
C4—H4
C4—C3i
C3—C4i
C3—H3
C7—H7
1.353 (3)
C7—C8
C7—C6
C8—H8
C8—C9
1.393 (3)
1.393 (3)
0.9300
1.387 (3)
1.462 (3)
1.397 (3)
0.9300
1.390 (3)
1.393 (3)
0.9300
1.354 (3)
1.359 (3)
1.360 (3)
1.468 (3)
1.403 (3)
1.399 (3)
0.9300
1.393 (3)
1.393 (3)
0.9300
C5—C6
C5—C11
C10—H10
C10—C11
C10—C9
C11—H11
C9—H9
0.9300
0.9300
C1—N2—C6
C1—N1—C5
C4—C2—C1
C3—C2—C1
C3—C2—C4
N2—C1—N1
N2—C1—C2
N1—C1—C2
C2—C4—H4
C3i—C4—C2
C3i—C4—H4
C2—C3—H3
C4i—C3—C2
C4i—C3—H3
C8—C7—H7
C8—C7—C6
C6—C7—H7
C7—C8—H8
103.92 (17)
103.78 (17)
119.27 (17)
121.40 (19)
119.32 (17)
116.20 (16)
121.62 (19)
122.17 (18)
119.6
120.73 (18)
119.6
120.0
119.95 (18)
120.0
116.3
C9—C8—C7
C9—C8—H8
N1—C5—C6
N1—C5—C11
C11—C5—C6
N2—C6—C7
N2—C6—C5
C7—C6—C5
C11—C10—H10
C11—C10—C9
C9—C10—H10
C5—C11—H11
C10—C11—C5
C10—C11—H11
C8—C9—C10
C8—C9—H9
C10—C9—H9
129.0 (2)
115.5
107.83 (17)
123.49 (19)
128.68 (19)
123.3 (2)
108.26 (17)
128.43 (19)
115.6
128.8 (2)
115.6
116.4
127.3 (2)
116.4
130.3 (2)
114.8
127.4 (2)
116.3
115.5
114.8
N1—C5—C6—N2
N1—C5—C6—C7
N1—C5—C11—C10
C1—N2—C6—C7
C1—N2—C6—C5
C1—N1—C5—C6
C1—N1—C5—C11
C1—C2—C4—C3i
−0.7 (2)
C3—C2—C4—C3i
C7—C8—C9—C10
C8—C7—C6—N2
C8—C7—C6—C5
C5—N1—C1—N2
C5—N1—C1—C2
C6—N2—C1—N1
C6—N2—C1—C2
0.1 (3)
−0.4 (4)
−179.84 (19)
1.3 (3)
−0.7 (2)
178.42 (16)
0.3 (2)
−178.84 (16)
178.37 (19)
179.60 (19)
−178.87 (18)
0.2 (2)
0.8 (2)
−178.90 (19)
178.97 (16)
Acta Cryst. (2018). C74, 171-176
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supporting information
C1—C2—C3—C4i
C4—C2—C1—N2
C4—C2—C1—N1
C4—C2—C3—C4i
C3—C2—C1—N2
C3—C2—C1—N1
−178.94 (16)
12.0 (3)
−167.08 (18)
−0.1 (3)
−169.12 (17)
11.8 (3)
C6—C7—C8—C9
C6—C5—C11—C10
C11—C5—C6—N2
C11—C5—C6—C7
C11—C10—C9—C8
C9—C10—C11—C5
0.6 (4)
0.0 (4)
178.99 (19)
−2.0 (3)
−1.6 (4)
2.1 (4)
Symmetry code: (i) −x+1, −y+1, −z.
Acta Cryst. (2018). C74, 171-176
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