Crystal structure and fluorescence study of (μ-N-[(3,5-dimethyl-1H-pyrrol-2-yl)methyl­idene]-N-{4-[(3,5-dimethyl-1H-pyrrol-2-yl)methyl­idene­aza­nium­yl]phen­yl}aza­nium)bis­[di­fluorido­boron(IV)]

Liu, X.; Li, T.; Yin, Z.

doi:10.1107/S2056989021000463

research communications

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ISSN: 2056-9890

Volume 77| Part 2| February 2021| Pages 126-129

https://doi.org/10.1107/S2056989021000463

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Crystal structure and fluorescence study of (μ-N-[(3,5-dimethyl-1H-pyrrol-2-yl)methylidene]-N-{4-[(3,5-dimethyl-1H-pyrrol-2-yl)methylideneazaniumyl]phenyl}azanium)bis[difluoridoboron(IV)]

Xiaoxue Liu,^a Tuo Li ^a and Zhenming Yin ^a ^*

^aCollege of Chemistry, Tianjin Key Laboratory of Structure and Performance for Functional Molecule, Tianjin Normal University, Tianjin 300387, People's Republic of China
^*Correspondence e-mail: tjyinzm@aliyun.com

Edited by J. Ellena, Universidade de Sâo Paulo, Brazil (Received 2 December 2020; accepted 13 January 2021; online 15 January 2021)

The title molecule, C₂₀H₂₀B₂F₄N₄, assumes a planar conformation with all atoms apart from the F atoms lying on the symmetry plane. Each boron atom is four-coordinated by two fluorine atoms, a pyrrole N atom and an imine N atom. Both imine CH=N groups adopt a trans conformation. In the crystal, the molecules self-assemble into a pillar structure through C—H⋯F hydrogen bonds and π–π interactions. The UV–vis spectrum and fluorescence spectra of the title compound are also reported.

Keywords: 2-iminopyrrole; BF₂ complex; crystal structure; fluorescence.

CCDC reference: 2055687

1. Chemical context

Fluorescent materials are gradually becoming a necessity in modern chemistry and biology because of their unique advantages in the characterization of life activities in living organisms (Zhang et al., 2019 ). Boron-dipyrromethene (BODIPY) is a frequently reported fluorescent structure (Boens et al., 2015 ). Its planar structure endows BODIPY compounds with strong fluorescence emission under the action of excitation light. Such compounds also have high molar absorption coefficient, good light stability and excitation wavelengths in the visible to near infrared region. In addition, their structures can easily be modified and they are not easily affected by the environment (Loudet & Burgess, 2007 ). The success of BODIPY dyes has led to research on similar structures such as aza-BODIPY structures (Bodio & Goze, 2019 ), boron complexes of iminopyrrolide ligands (BOIMPY; Suresh et al., 2012 , 2015 ; Lee et al., 2016 ), bis(difluoroboron)-1,2-bis{(pyrrol-2-yl)methylene}hydrazine (BOPHY; Boodts et al., 2018 ) structures and other novel organoboron fluorescence materials (Frath et al., 2014 ).

BOIMPY has a similar structure to BODIPY, in which the pyrrole ring is located in the same plane as the aromatic ring, the boron atom and the methylene bridge. More importantly, BOIMPY has the advantage of lower molecular symmetry, which can overcome the shortcoming of the short Stokes shifts of BODIPY (Lee et al., 2016). In contrast to BODIPY, studies on BOIMPY are still rare. Herein, we report the synthesis, crystal structure and spectroscopic properties of a new BOIMPY compound, bis(difluoroboron)bis(pyrrol-2-yl)methylenediaminophenylene.

2. Structural commentary

The structure of the title compound is shown in Fig. 1. All atoms lie on the symmetry plane except for the F atoms, which deviate from it by 1.136 (1) Å (F1) and 1.135 (1) Å (F2) on the same side of the molecule. Each boron atom is four-coordinated by two fluorine atoms, a pyrrole N atom and an imine N atom. The N1—B1, N2—B1, N3—B2 and N4—B2 bond lengths [1.544 (4), 1.604 (4), 1.610 (4) and 1.538 (4) Å, respectively] are longer than the accepted mean value for a B—N bond (1.54–1.55Å) in BODIPY compounds reported in the literature (Madhu & Ravikanth, 2014 ). The two imine CH=N groups adopt a trans conformation and at 1.339 (4) and 1.321 (4) Å their bond lengths are longer than that in the free imino-pyrrole ligand (1.263 Å; Xu et al., 2010 ) while the C8—N2 and C11—N3 bonds [both 1.408 (4) Å] are shorter than in the free imino-pyrrole ligand (1.424 Å; Xu et al., 2010).

Figure 1
ORTEP diagrams for the title compound, (a) top view and (b) side view, with displacement ellipsoids drawn at the 30% probability level.

3. Supramolecular features

In the crystal, the molecules are linked by C6—H6B⋯F2 hydrogen bonds between methyl group and the fluorine atom (Table 1), and π–π interactions between benzene rings [Cg1⋯Cg1(−x + 1, y + $[{1\over 2}]$ , −z + 1) = 3.7521 (2) Å; Cg1 is the centroid of the C8–C13 ring] into one-dimensional pillars along the b-axis direction. Within the pillar, neighbouring molecules are oriented in opposite directions (Fig. 2). The pillars are held together by van der Waals interactions, forming a herringbone structure. A perspective view of the crystal packing within the unit cell is depicted in Fig. 3.

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C6—H6B⋯F2ⁱ	0.96	2.49	3.336 (3)	147
Symmetry code: (i) $[-x+1, y+{\script{1\over 2}}, -z+1]$ .

Figure 2
Part of the pillar structure showing molecules linked by C—H⋯Fⁱ hydrogen bonds and π–π interaction [symmetry code: (i) −x + 1, y + $[{1\over 2}]$ , −z + 1].

Figure 3
Part of the packing diagram for the title compound.

4. Database survey

A search in the Cambridge Structural Database (CSD, version 5.41, update of November 2019; Groom et al., 2016 ) returned 21 entries for iminopyrrolyl boron complexes. Two diphenylboron analogues of the title compound were reported by Gomes and coworkers [KEDHIM (Suresh et al., 2012) and TUJFOV (Suresh et al., 2015)]. In their crystals, the respective dihedral angles between the 2-formiminopyrrolyl unit and the phenyl ring are −47.2 (3) and 46.1 (11)°.

5. UV–vis spectrum and fluorescence spectra

The UV–vis spectrum and fluorescence spectra of the title compound are shown in Figs. 4 and 5, respectively. The UV–vis spectrum is solvent independent. A THF solution of the title compound displays intense broad absorption at 474 nm, which can be assigned to the n–π* transition of the iminopyrrolyl group. The title compound has two emission peaks at 528 nm and 574 nm. It can be seen that the fluorescence intensity of title compound is greatly affected by the solvents. In the polar solvent DMSO, the fluorescence intensity is much weaker than that in the apolar solvent CHCl₃, which is similar to a previous report (Li et al., 2018 ). The title compound shows substantial bathochromic shifts in both absorption and emission when compared to the diphenylboron analogues reported by Gomes and coworkers (Suresh et al., 2012), which can be ascribed to the planar structure of the title compound.

Figure 4
UV–vis spectrum of the title compound in THF solution (1 × 10 ⁻⁵ M).

Figure 5
Fluorescence spectra of the title compound in different solutions (1 × 10 ⁻⁵ M).

6. Synthesis and crystallization

To a solution of bis(pyrrol-2-yl)methylenediaminophenylene (1 mmol, 0.32 g) and triethylamine (4.2 mmol, 6 mL) in dry dichloromethane (15 mL) was slowly added boron trifluoride ethyl ether (7.2 mmol, 2 mL). The resulting solution was stirred overnight, and then saturated potassium carbonate solution was added and stirred for 30 minutes. The resulting solution was extracted and evaporated under vacuum to dryness. The residue was purified by column chromatography eluting with CH₂Cl₂ and petroleum ether (v:v 1:2) to give an orange product, m.p. 435 K. ¹H NMR (400 MHz, CDCl₃) δ 8.101 (s, 2H, =CH–), 7.519 (s, 4H, Ar C—H), 6.007 (s, 2H, pyrrole CH), 2.412 (s, 6H, –CH₃), 2.270 (s, 6H, –CH₃). HRMS (ESI) m/z: calculated for C₂₀H₂₀B₂F₄N₄, (M + H)⁺ 415.01521; found 415.01533.

7. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2. H atoms were located in a difference-Fourier map, placed in calculated positions (C—H = 0.93 or 0.96 Å) and included in the final cycles of refinement using a riding model, with U_iso(H) = 1.2U_eq(C) or 1.5U_eq(C-methyl). Idealized methyl groups were refined as rotating groups.

Table 2
Experimental details

Crystal data
Chemical formula	C₂₀H₂₀B₂F₄N₄
M_r	414.02
Crystal system, space group	Orthorhombic, Pnma
Temperature (K)	110
a, b, c (Å)	20.2495 (9), 6.8046 (5), 13.4969 (5)
V (Å³)	1859.74 (17)
Z	4
Radiation type	Cu Kα
μ (mm⁻¹)	0.99
Crystal size (mm)	0.25 × 0.14 × 0.13

Data collection
Diffractometer	Rigaku Oxford Diffraction SuperNova, Dual, Cu at zero, AtlasS2
Absorption correction	Multi-scan (CrysAlis PRO; Rigaku OD, 2015 $[Rigaku, OD (2015). CrysAlis PRO. Rigaku Oxford Diffraction, Yarnton, England.]$ )
T_min, T_max	0.478, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections	4486, 1815, 1375
R_int	0.046
(sin θ/λ)_max (Å⁻¹)	0.597

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.048, 0.126, 1.01
No. of reflections	1815
No. of parameters	179
No. of restraints	6
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.27, −0.32
Computer programs: CrysAlis PRO (Rigaku OD, 2015 $[Rigaku, OD (2015). CrysAlis PRO. Rigaku Oxford Diffraction, Yarnton, England.]$ ), SHELXT (Sheldrick, 2015a ), SHELXL (Sheldrick, 2015b ) and OLEX2 (Dolomanov et al., 2009 ).

Supporting information

CCDC reference: 2055687

Crystal structure: contains datablock I. DOI: https://doi.org/10.1107/S2056989021000463/ex2040sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989021000463/ex2040Isup2.hkl

checkCIF report

Computing details top

Data collection: CrysAlis PRO (Rigaku OD, 2015); cell refinement: CrysAlis PRO (Rigaku OD, 2015); data reduction: CrysAlis PRO (Rigaku OD, 2015); program(s) used to solve structure: ShelXT (Sheldrick, 2015a); program(s) used to refine structure: SHELXL (Sheldrick, 2015b); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009).

(µ-N-[(3,5-Dimethyl-1H-pyrrol-2-yl)methylidene]N-{{4-[(3,5-dimethyl-1H-pyrrol-2-yl)methylideneazaniumyl]phenyl}azanium)bis[difluoridoboron(IV)] top

Crystal data top

C₂₀H₂₀B₂F₄N₄	D_x = 1.479 Mg m⁻³
M_r = 414.02	Cu Kα radiation, λ = 1.54184 Å
Orthorhombic, Pnma	Cell parameters from 1337 reflections
a = 20.2495 (9) Å	θ = 3.9–73.0°
b = 6.8046 (5) Å	µ = 0.99 mm⁻¹
c = 13.4969 (5) Å	T = 110 K
V = 1859.74 (17) Å³	Block, brown
Z = 4	0.25 × 0.14 × 0.13 mm
F(000) = 856

Data collection top

Rigaku Oxford Diffraction SuperNova, Dual, Cu at zero, AtlasS2 diffractometer	1815 independent reflections
Radiation source: micro-focus sealed X-ray tube, SuperNova (Cu) X-ray Source	1375 reflections with I > 2σ(I)
Mirror monochromator	R_int = 0.046
Detector resolution: 5.2740 pixels mm^-1	θ_max = 67.1°, θ_min = 3.9°
ω scans	h = −17→24
Absorption correction: multi-scan (CrysAlisPro; Rigaku OD, 2015)	k = −7→8
T_min = 0.478, T_max = 1.000	l = −13→16
4486 measured reflections

Refinement top

Refinement on F²	Primary atom site location: dual
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.048	H-atom parameters constrained
wR(F²) = 0.126	w = 1/[σ²(F_o²) + (0.0648P)²] where P = (F_o² + 2F_c²)/3
S = 1.01	(Δ/σ)_max < 0.001
1815 reflections	Δρ_max = 0.27 e Å⁻³
179 parameters	Δρ_min = −0.32 e Å⁻³
6 restraints

Special details top

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq	Occ. (<1)
F1	0.47574 (6)	0.5830 (2)	0.79642 (10)	0.0251 (3)
F2	0.27560 (6)	0.58327 (19)	0.39551 (9)	0.0214 (3)
N1	0.57949 (12)	0.750000	0.83332 (18)	0.0181 (6)
N2	0.54122 (11)	0.750000	0.66808 (19)	0.0152 (5)
N3	0.37529 (11)	0.750000	0.33323 (18)	0.0146 (5)
N4	0.27854 (11)	0.750000	0.2358 (2)	0.0167 (6)
C1	0.63149 (14)	0.750000	0.7670 (2)	0.0175 (6)
C2	0.60426 (15)	0.750000	0.9262 (2)	0.0196 (7)
C3	0.67356 (15)	0.750000	0.9190 (2)	0.0215 (7)
H3	0.702742	0.750000	0.972227	0.026*
C4	0.69141 (14)	0.750000	0.8194 (2)	0.0183 (6)
C5	0.56119 (16)	0.750000	1.0158 (2)	0.0256 (7)
H5A	0.550754	0.617060	1.033709	0.038*	0.5
H5B	0.521163	0.820249	1.001678	0.038*	0.5
H5C	0.583911	0.812692	1.069602	0.038*	0.5
C6	0.76010 (14)	0.750000	0.7777 (3)	0.0223 (7)
H6A	0.788406	0.827009	0.819538	0.034*	0.5
H6B	0.759521	0.805418	0.712325	0.034*	0.5
H6C	0.776318	0.617573	0.774672	0.034*	0.5
C7	0.60731 (14)	0.750000	0.6711 (2)	0.0174 (6)
H7	0.633991	0.750000	0.615007	0.021*
C8	0.50243 (14)	0.750000	0.5815 (2)	0.0153 (6)
C9	0.43380 (14)	0.750000	0.5922 (2)	0.0190 (7)
H9	0.415253	0.750000	0.655206	0.023*
C10	0.39326 (14)	0.750000	0.5099 (2)	0.0212 (7)
H10	0.347688	0.750000	0.518466	0.025*
C11	0.41924 (14)	0.750000	0.4141 (2)	0.0150 (6)
C12	0.48845 (14)	0.750000	0.4035 (2)	0.0169 (6)
H12	0.507081	0.750000	0.340566	0.020*
C13	0.52863 (13)	0.750000	0.4856 (2)	0.0183 (7)
H13	0.574212	0.750000	0.477137	0.022*
C14	0.39064 (13)	0.750000	0.2381 (2)	0.0172 (6)
H14	0.433769	0.750000	0.214397	0.021*
C15	0.33467 (13)	0.750000	0.1766 (2)	0.0169 (6)
C16	0.31589 (16)	0.750000	0.0770 (2)	0.0199 (7)
C17	0.24674 (15)	0.750000	0.0784 (2)	0.0208 (7)
H17	0.219502	0.750000	0.022896	0.025*
C18	0.22542 (14)	0.750000	0.1769 (2)	0.0192 (7)
C19	0.35899 (15)	0.750000	−0.0125 (2)	0.0260 (7)
H19A	0.358113	0.622295	−0.042734	0.039*	0.5
H19B	0.403441	0.781639	0.006382	0.039*	0.5
H19C	0.343184	0.846066	−0.058910	0.039*	0.5
C20	0.15647 (15)	0.750000	0.2183 (3)	0.0276 (8)
H20A	0.138964	0.881066	0.216494	0.041*	0.5
H20B	0.157389	0.704099	0.285535	0.041*	0.5
H20C	0.129033	0.664835	0.179283	0.041*	0.5
B1	0.51243 (16)	0.750000	0.7788 (2)	0.0164 (7)
B2	0.29629 (15)	0.750000	0.3467 (3)	0.0163 (7)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
F1	0.0203 (6)	0.0351 (8)	0.0197 (6)	−0.0089 (6)	−0.0011 (5)	0.0052 (6)
F2	0.0177 (6)	0.0275 (7)	0.0190 (6)	−0.0052 (5)	0.0007 (5)	0.0037 (6)
N1	0.0159 (12)	0.0255 (14)	0.0128 (12)	0.000	−0.0019 (10)	0.000
N2	0.0108 (10)	0.0211 (13)	0.0137 (12)	0.000	−0.0022 (10)	0.000
N3	0.0109 (11)	0.0196 (12)	0.0133 (12)	0.000	0.0000 (10)	0.000
N4	0.0114 (11)	0.0199 (13)	0.0187 (13)	0.000	−0.0012 (10)	0.000
C1	0.0144 (13)	0.0195 (15)	0.0186 (15)	0.000	−0.0019 (12)	0.000
C2	0.0233 (15)	0.0194 (15)	0.0163 (15)	0.000	−0.0034 (13)	0.000
C3	0.0203 (15)	0.0230 (16)	0.0213 (15)	0.000	−0.0064 (13)	0.000
C4	0.0147 (13)	0.0166 (14)	0.0235 (15)	0.000	−0.0078 (12)	0.000
C5	0.0239 (14)	0.0358 (19)	0.0169 (15)	0.000	−0.0045 (13)	0.000
C6	0.0140 (13)	0.0262 (17)	0.0267 (17)	0.000	−0.0062 (13)	0.000
C7	0.0115 (13)	0.0221 (15)	0.0185 (15)	0.000	−0.0007 (12)	0.000
C8	0.0136 (13)	0.0182 (14)	0.0142 (15)	0.000	−0.0024 (11)	0.000
C9	0.0136 (13)	0.0309 (17)	0.0126 (14)	0.000	0.0015 (12)	0.000
C10	0.0099 (12)	0.0345 (17)	0.0193 (16)	0.000	0.0000 (12)	0.000
C11	0.0128 (13)	0.0179 (14)	0.0144 (14)	0.000	−0.0024 (11)	0.000
C12	0.0123 (13)	0.0259 (15)	0.0124 (14)	0.000	0.0029 (11)	0.000
C13	0.0085 (12)	0.0255 (16)	0.0209 (16)	0.000	−0.0008 (12)	0.000
C14	0.0118 (13)	0.0200 (15)	0.0198 (15)	0.000	−0.0010 (12)	0.000
C15	0.0119 (12)	0.0179 (14)	0.0209 (16)	0.000	0.0006 (12)	0.000
C16	0.0213 (14)	0.0212 (15)	0.0173 (14)	0.000	−0.0064 (13)	0.000
C17	0.0196 (14)	0.0264 (17)	0.0166 (15)	0.000	−0.0093 (13)	0.000
C18	0.0158 (14)	0.0235 (16)	0.0183 (15)	0.000	−0.0044 (12)	0.000
C19	0.0229 (15)	0.0370 (18)	0.0182 (16)	0.000	−0.0004 (13)	0.000
C20	0.0148 (14)	0.045 (2)	0.0234 (17)	0.000	−0.0037 (13)	0.000
B1	0.0160 (15)	0.0232 (18)	0.0100 (16)	0.000	−0.0018 (13)	0.000
B2	0.0092 (14)	0.0238 (18)	0.0158 (15)	0.000	−0.0036 (13)	0.000

Geometric parameters (Å, º) top

F1—B1	1.378 (2)	C6—H6C	0.9600
F2—B2	1.377 (2)	C7—H7	0.9300
N1—C1	1.382 (4)	C8—C9	1.397 (4)
N1—C2	1.350 (4)	C8—C13	1.399 (4)
N1—B1	1.544 (4)	C9—H9	0.9300
N2—C7	1.339 (4)	C9—C10	1.381 (4)
N2—C8	1.408 (4)	C10—H10	0.9300
N2—B1	1.604 (4)	C10—C11	1.396 (4)
N3—C11	1.408 (4)	C11—C12	1.409 (4)
N3—C14	1.321 (4)	C12—H12	0.9300
N3—B2	1.610 (4)	C12—C13	1.374 (4)
N4—C15	1.389 (4)	C13—H13	0.9300
N4—C18	1.338 (4)	C14—H14	0.9300
N4—B2	1.538 (4)	C14—C15	1.404 (4)
C1—C4	1.404 (4)	C15—C16	1.398 (4)
C1—C7	1.384 (4)	C16—C17	1.400 (4)
C2—C3	1.407 (4)	C16—C19	1.491 (5)
C2—C5	1.491 (5)	C17—H17	0.9300
C3—H3	0.9300	C17—C18	1.398 (5)
C3—C4	1.393 (5)	C18—C20	1.504 (4)
C4—C6	1.500 (4)	C19—H19A	0.9600
C5—H5A	0.9600	C19—H19B	0.9600
C5—H5B	0.9600	C19—H19C	0.9600
C5—H5C	0.9600	C20—H20A	0.9600
C6—H6A	0.9600	C20—H20B	0.9600
C6—H6B	0.9600	C20—H20C	0.9600

C1—N1—B1	111.2 (2)	N3—C11—C12	123.4 (3)
C2—N1—C1	108.6 (2)	C10—C11—N3	118.7 (2)
C2—N1—B1	140.2 (3)	C10—C11—C12	117.9 (3)
C7—N2—C8	125.6 (3)	C11—C12—H12	119.7
C7—N2—B1	109.6 (2)	C13—C12—C11	120.5 (3)
C8—N2—B1	124.8 (2)	C13—C12—H12	119.7
C11—N3—B2	122.7 (2)	C8—C13—H13	119.3
C14—N3—C11	127.2 (2)	C12—C13—C8	121.4 (3)
C14—N3—B2	110.1 (2)	C12—C13—H13	119.3
C15—N4—B2	111.6 (2)	N3—C14—H14	123.7
C18—N4—C15	108.4 (3)	N3—C14—C15	112.6 (3)
C18—N4—B2	140.0 (3)	C15—C14—H14	123.7
N1—C1—C4	109.4 (3)	N4—C15—C14	108.7 (3)
N1—C1—C7	109.6 (2)	N4—C15—C16	109.3 (2)
C7—C1—C4	140.9 (3)	C16—C15—C14	142.0 (3)
N1—C2—C3	107.9 (3)	C15—C16—C17	105.0 (3)
N1—C2—C5	122.4 (3)	C15—C16—C19	128.4 (3)
C3—C2—C5	129.8 (3)	C17—C16—C19	126.6 (3)
C2—C3—H3	125.5	C16—C17—H17	125.6
C4—C3—C2	109.0 (3)	C18—C17—C16	108.7 (3)
C4—C3—H3	125.5	C18—C17—H17	125.6
C1—C4—C6	127.8 (3)	N4—C18—C17	108.5 (3)
C3—C4—C1	105.2 (3)	N4—C18—C20	121.7 (3)
C3—C4—C6	127.1 (3)	C17—C18—C20	129.8 (3)
C2—C5—H5A	109.5	C16—C19—H19A	109.5
C2—C5—H5B	109.5	C16—C19—H19B	109.5
C2—C5—H5C	109.5	C16—C19—H19C	109.5
H5A—C5—H5B	109.5	H19A—C19—H19B	109.5
H5A—C5—H5C	109.5	H19A—C19—H19C	109.5
H5B—C5—H5C	109.5	H19B—C19—H19C	109.5
C4—C6—H6A	109.5	C18—C20—H20A	109.5
C4—C6—H6B	109.5	C18—C20—H20B	109.5
C4—C6—H6C	109.5	C18—C20—H20C	109.5
H6A—C6—H6B	109.5	H20A—C20—H20B	109.5
H6A—C6—H6C	109.5	H20A—C20—H20C	109.5
H6B—C6—H6C	109.5	H20B—C20—H20C	109.5
N2—C7—C1	112.5 (3)	F1—B1—F1ⁱ	111.1 (3)
N2—C7—H7	123.8	F1—B1—N1	113.08 (16)
C1—C7—H7	123.8	F1ⁱ—B1—N1	113.08 (16)
C9—C8—N2	118.0 (3)	F1—B1—N2	110.87 (17)
C9—C8—C13	118.2 (3)	F1ⁱ—B1—N2	110.87 (17)
C13—C8—N2	123.8 (3)	N1—B1—N2	97.1 (2)
C8—C9—H9	119.7	F2—B2—F2ⁱ	110.9 (2)
C10—C9—C8	120.6 (3)	F2—B2—N3	110.86 (15)
C10—C9—H9	119.7	F2ⁱ—B2—N3	110.86 (15)
C9—C10—H10	119.3	F2—B2—N4	113.23 (15)
C9—C10—C11	121.4 (3)	F2ⁱ—B2—N4	113.23 (15)
C11—C10—H10	119.3	N4—B2—N3	97.0 (2)

N1—C1—C4—C3	0.000 (1)	C11—N3—C14—C15	180.000 (1)
N1—C1—C4—C6	180.000 (1)	C11—N3—B2—F2ⁱ	61.82 (18)
N1—C1—C7—N2	0.000 (1)	C11—N3—B2—F2	−61.81 (18)
N1—C2—C3—C4	0.000 (1)	C11—N3—B2—N4	180.000 (1)
N2—C8—C9—C10	180.000 (1)	C11—C12—C13—C8	0.000 (1)
N2—C8—C13—C12	180.000 (1)	C13—C8—C9—C10	0.000 (1)
N3—C11—C12—C13	180.000 (1)	C14—N3—C11—C10	180.000 (1)
N3—C14—C15—N4	0.000 (1)	C14—N3—C11—C12	0.000 (1)
N3—C14—C15—C16	180.000 (1)	C14—N3—B2—F2	118.19 (18)
N4—C15—C16—C17	0.000 (1)	C14—N3—B2—F2ⁱ	−118.18 (18)
N4—C15—C16—C19	180.000 (1)	C14—N3—B2—N4	0.000 (1)
C1—N1—C2—C3	0.000 (1)	C14—C15—C16—C17	180.000 (1)
C1—N1—C2—C5	180.000 (1)	C14—C15—C16—C19	0.000 (1)
C1—N1—B1—F1ⁱ	−116.3 (2)	C15—N4—C18—C17	0.000 (1)
C1—N1—B1—F1	116.3 (2)	C15—N4—C18—C20	180.000 (1)
C1—N1—B1—N2	0.000 (1)	C15—N4—B2—F2ⁱ	116.33 (18)
C2—N1—C1—C4	0.000 (1)	C15—N4—B2—F2	−116.32 (18)
C2—N1—C1—C7	180.000 (1)	C15—N4—B2—N3	0.000 (1)
C2—N1—B1—F1	−63.7 (2)	C15—C16—C17—C18	0.000 (1)
C2—N1—B1—F1ⁱ	63.7 (2)	C16—C17—C18—N4	0.000 (1)
C2—N1—B1—N2	180.000 (1)	C16—C17—C18—C20	180.000 (1)
C2—C3—C4—C1	0.000 (1)	C18—N4—C15—C14	180.000 (1)
C2—C3—C4—C6	180.000 (1)	C18—N4—C15—C16	0.000 (1)
C4—C1—C7—N2	180.000 (1)	C18—N4—B2—F2ⁱ	−63.67 (18)
C5—C2—C3—C4	180.000 (1)	C18—N4—B2—F2	63.68 (18)
C7—N2—C8—C9	180.000 (1)	C18—N4—B2—N3	180.000 (1)
C7—N2—C8—C13	0.000 (1)	C19—C16—C17—C18	180.0
C7—N2—B1—F1ⁱ	118.07 (18)	B1—N1—C1—C4	180.000 (1)
C7—N2—B1—F1	−118.07 (18)	B1—N1—C1—C7	0.000 (1)
C7—N2—B1—N1	0.000 (1)	B1—N1—C2—C3	180.000 (1)
C7—C1—C4—C3	180.000 (1)	B1—N1—C2—C5	0.000 (1)
C7—C1—C4—C6	0.000 (1)	B1—N2—C7—C1	0.000 (1)
C8—N2—C7—C1	180.000 (1)	B1—N2—C8—C9	0.000 (1)
C8—N2—B1—F1ⁱ	−61.93 (18)	B1—N2—C8—C13	180.000 (1)
C8—N2—B1—F1	61.93 (18)	B2—N3—C11—C10	0.000 (1)
C8—N2—B1—N1	180.000 (1)	B2—N3—C11—C12	180.000 (1)
C8—C9—C10—C11	0.000 (1)	B2—N3—C14—C15	0.000 (1)
C9—C8—C13—C12	0.000 (1)	B2—N4—C15—C14	0.000 (1)
C9—C10—C11—N3	180.000 (1)	B2—N4—C15—C16	180.000 (1)
C9—C10—C11—C12	0.000 (1)	B2—N4—C18—C17	180.000 (1)
C10—C11—C12—C13	0.000 (1)	B2—N4—C18—C20	0.000 (1)

Symmetry code: (i) x, −y+3/2, z.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C6—H6B···F2ⁱⁱ	0.96	2.49	3.336 (3)	147

Symmetry code: (ii) −x+1, y+1/2, −z+1.

Funding information

Funding for this research was provided by: National Natural Science Foundation of China (award No. 21172174).

References

Bodio, E. & Goze, C. (2019). Dyes Pigments, 160, 700–710. Web of Science CrossRef CAS Google Scholar
Boens, N., Verbelen, B. & Dehaen, W. (2015). Eur. J. Org. Chem. pp. 6577–6595. Web of Science CrossRef Google Scholar
Boodts, S., Fron, E., Hofkens, J. & Dehaen, W. (2018). Coord. Chem. Rev. 371, 1–10. Web of Science CrossRef CAS Google Scholar
Dolomanov, O. V., Bourhis, L. J., Gildea, R. J., Howard, J. A. K. & Puschmann, H. (2009). J. Appl. Cryst. 42, 339–341. Web of Science CrossRef CAS IUCr Journals Google Scholar
Frath, D., Massue, J., Ulrich, G. & Ziessel, R. (2014). Angew. Chem. Int. Ed. 53, 2290–2310. Web of Science CrossRef CAS Google Scholar
Groom, C. R., Bruno, I. J., Lightfoot, M. P. & Ward, S. C. (2016). Acta Cryst. B72, 171–179. Web of Science CrossRef IUCr Journals Google Scholar
Lee, B., Park, B. G., Cho, W., Lee, H. Y., Olasz, A., Chen, C.-H., Park, S. B. & Lee, D. (2016). Chem. Eur. J. 22, 17321–17328. Web of Science CSD CrossRef CAS PubMed Google Scholar
Li, T., Xu, L. & Yin, Z. (2018). Chinese J. Struct. Chem, 37, 809–904. Google Scholar
Loudet, A. & Burgess, K. (2007). Chem. Rev. 107, 4891–4932. Web of Science CrossRef PubMed CAS Google Scholar
Madhu, I. & Ravikanth, M. (2014). Inorg. Chem. 53, 1646–1653. Web of Science CSD CrossRef CAS PubMed Google Scholar
Rigaku, OD (2015). CrysAlis PRO. Rigaku Oxford Diffraction, Yarnton, England. Google Scholar
Sheldrick, G. M. (2015a). Acta Cryst. A71, 3–8. Web of Science CrossRef IUCr Journals Google Scholar
Sheldrick, G. M. (2015b). Acta Cryst. C71, 3–8. Web of Science CrossRef IUCr Journals Google Scholar
Suresh, D., Gomes, C. S. B., Gomes, P. T., Di Paolo, R. E., Macanica, A. L., Calhorda, M. J., Charas, A., Morgado, J. & Duarte, M. T. (2012). Dalton Trans. 41, 8902–8905. Web of Science CSD CrossRef Google Scholar
Suresh, D., Gomes, C. S. B., Lopes, P. S., Figueira, C. A., Ferreira, B., Gomes, P. T., Di Paolo, R. E., Maçanita, A. L., Duarte, M. T., Charas, A., Morgado, J., Vila-Viçosa, D. & Calhorda, M. J. (2015). Chem. Eur. J. 21, 9133–9149. Web of Science CSD CrossRef CAS PubMed Google Scholar
Xu, L., Liu, S. Y. & Yin, Z. (2010). Chin. J. Struct. Chem. 29, 613–617. CAS Google Scholar
Zhang, J., Chai, X., He, X.-P., Kim, H.-J., Yoon, J. & Tian, H. (2019). Chem. Soc. Rev. 48, 683–722. Web of Science CrossRef CAS PubMed Google Scholar

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