Crystal structure of 4,4′-(diazenediyl)dipyridinium nitrate perchlorate

Qiu, Q.-M.; Song, J.-B.; Dong, A.-G.; Li, C.-T.; Zheng, Z.-Y.

doi:10.1107/S2056989022007885

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Volume 78| Part 9| September 2022| Pages 897-899

https://doi.org/10.1107/S2056989022007885

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Crystal structure of 4,4′-(diazenediyl)dipyridinium nitrate perchlorate

Qi-Ming Qiu,^a ^* Jian-Biao Song,^b Ai-Guo Dong,^a Chuan-Tao Li ^a and Zhi-Yuan Zheng ^a

^aSchool of Science, China University of Geosciences, Beijing 100083, People's Republic of China, and ^bBeijing Chaoyang Foreign Language School, Beijing 100101, People's Republic of China
^*Correspondence e-mail: qiuqiming890521@163.com

Edited by A. V. Yatsenko, Moscow State University, Russia (Received 8 July 2022; accepted 5 August 2022; online 12 August 2022)

The title compound, C₁₀H₁₀N₄²⁺·NO₃⁻·ClO₄⁻, was obtained unexpectedly by the reaction of Co(ClO₄)₂·6H₂O and cytidine-5′-monophosphate with 4,4′-azopyridine in an aqueous solution of nitric acid. The molecular structure comprises two planar 4,4′-diazenediyldipyridinium dications lying on inversion centres and perchlorate and nitrate anions in general positions. In the crystal, N—H⋯O hydrogen bonds between dications and anions lead to the formation of [232] chains.

Keywords: crystal structure; 4,4′-azopyridine; hydrogen bonds.

CCDC reference: 2163316

1. Chemical context

If a molecule contains two connected six-membered rings, and each of them contains N atoms, this molecule can coordinate various metal ions in different ways. In particular, molecules containing two or more pyridine rings are perfect bridging ligands to form supramolecular structures (Zhang et al., 2005 ; Rusu et al., 2012 ; Theilmann et al., 2009 ; Aakeröy et al., 2013a ,b ; Huang et al., 2016 ; Santana et al., 2017 ; Hutchins et al., 2018 ). In our previous work (Qiu et al., 2017 ), we used, together with a cytidine-5′-monophosphate mononucleotide (CMP), an auxiliary ligands, namely 4,4′-azopyridine (azpy), to completely coordinate a metal ion to restrain the non-enzymatic hydrolysis of the phosphate group catalyzed by these ions, and we obtained the complex Co-CMP-azpy under pH = 5. As a result of the different charge states of CMP in aqueous solution, it seems to be meaningful to study nucleotide complexes at other pH values. Unexpectedly, single crystals of the title compound were obtained in a more acidic medium (pH = 3). The title compound is the first example of a salt of 4,4′-diazenediyldipyridinium dication with two different anions.

2. Structural commentary

The molecular structure of the title compound comprises two planar [within 0.261 (5) Å] 4,4′-diazenediyldipyridinium dications lying on inversion centers and perchlorate and nitrate anions in general positions (Fig. 1). A planar conformation of the 4,4′-diazenediyldipyridinium dications is commonly observed for this type of compound. However, in the structure of bis(4,4′-diazenediyldipyridinium) bis(μ-chloro)octachlorodibismuth (POPHIO; Klein, 2019a ) pyridinium rings are twisted by 19.0 (4)°, whereas in the structure of 4,4′-diazenediyldipyridinium bis(iodide) (POPKEN; Klein, 2019b ) the mean planes of the pyridinium rings form a dihedral angle of 84.1 (2)°. In the title 4,4'-diazenediyldipyridinium, the value of the dihedral angle between the planes passing through the pyridine rings is 0°.

Figure 1
The structure of the title compound showing the asymmetric unit (labelled) with cations supplemented by the symmetry-generated moieties (not labelled) at 1 − x, 2 − y, 2 − z (molecule containing N1/N3) and at 1 − x, 1 − y, 2 − z (molecule containing N2/N4). Displacement ellipsoids are drawn at the 50% probability level.

3. Supramolecular features

The 4,4′-diazenediyldipyridinium dications are connected by N—H⋯O hydrogen bonds with nitrate anions thus forming chains directed along [232] (Fig. 2, Table 1). The perchlorate anions are attached to these chains via N—H⋯O hydrogen bonds. C—H⋯O interactions are also observed.

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N2—H2B⋯O2ⁱ	0.86	2.47	3.046 (5)	125
N2—H2B⋯O1ⁱ	0.86	1.97	2.833 (4)	177
N2—H2B⋯N5ⁱ	0.86	2.58	3.372 (4)	153
N1—H1B⋯O4ⁱⁱ	0.86	2.42	3.078 (5)	134
N1—H1B⋯O1	0.86	2.22	2.989 (5)	150
C10—H10⋯O2ⁱ	0.93	2.46	3.049 (5)	122
C10—H10⋯O2ⁱⁱⁱ	0.93	2.42	3.257 (5)	150
C9—H9⋯O7ⁱⁱⁱ	0.93	2.58	3.191 (6)	124
C7—H7⋯O6^iv	0.93	2.45	3.285 (6)	150
C6—H6⋯O5^v	0.93	2.42	3.302 (6)	159
C6—H6⋯O4^v	0.93	2.56	3.318 (5)	139
C6—H6⋯Cl1^v	0.93	2.93	3.798 (4)	156
C5—H5⋯O7ⁱⁱ	0.93	2.53	3.447 (7)	169
C1—H1A⋯O3	0.93	2.28	3.117 (5)	150
Symmetry codes: (i) ; (ii) ; (iii) x, y, z+1; (iv) ; (v) .

Figure 2
Chain in the structure of the title compound formed by N—H⋯O hydrogen bonds (shown as dashed lines). Hydrogen atoms not involved in hydrogen bonding are omitted.

4. Database survey

A search of the Cambridge Structural Database (CSD version 5.40, update of March 2020; Groom et al., 2016 ) for the 4,4′-diazenediyldipyridinium dication gave 17 hits, of which four purely organic structures are closely related to the title compound. In the crystal of 4,4′-diazenediyldipyridinium dinitrate (HUKQIN; Felloni et al., 2002 ), N—H⋯O hydrogen bonds connect the dication to two anions, thus forming an island structure. The same type of structure is present in 4,4′-diazenediyldipyridinium dichloride (POPBUU; Klein, 2019c ) and 4,4′-diazenediyldipyridinium diiodide (POPKEN; Klein, 2019b). In the salt with partially deprotonated 1,2,4,5-benzenetetracarboxylic acid (BULJEZ; Ravat et al., 2015 ), the 4,4′-diazenediyldipyridinium dications act as the spacers that join the layers of hydrogen-bonded anions into a three-dimensional structure.

5. Synthesis and crystallization

An aqueous solution (5 mL) of cytidine-5′-monophosphate (32 mg, 0.10 mmol) was added to an aqueous solution (5 mL) of Co(ClO₄)₂·6H₂O (18 mg, 0.05 mmol). After stirring for 10 min, 4,4′-azopyridine (9 mg, 0.05 mmol) in distilled water (5 mL) was added to this mixture. Nitric acid was also dropped to it and the resulting solution (pH = 3) was stirred at room temperature for 30 min. Red block-shaped crystals were obtained by evaporation at room temperature for two weeks.

6. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2. All H atoms were positioned geometrically (N—H = 0.86 Å, C—H = 0.93 Å) and refined using a riding model with U_iso(H) = 1.2U_eq(N,C).

Table 2
Experimental details

Crystal data
Chemical formula	C₁₀H₁₀N₄²⁺·NO₃⁻·ClO₄⁻
M_r	347.68
Crystal system, space group	Triclinic, P $[\overline{1}]$
Temperature (K)	298
a, b, c (Å)	8.3023 (8), 10.0792 (9), 10.1052 (9)
α, β, γ (°)	116.966 (3), 105.481 (2), 92.871 (1)
V (Å³)	711.77 (11)
Z	2
Radiation type	Mo Kα
μ (mm⁻¹)	0.32
Crystal size (mm)	0.45 × 0.40 × 0.33

Data collection
Diffractometer	Bruker APEXII CCD
Absorption correction	Multi-scan (SADABS; Krause et al., 2015 )
T_min, T_max	0.873, 0.904
No. of measured, independent and observed [I > 2σ(I)] reflections	3625, 2466, 1896
R_int	0.034
(sin θ/λ)_max (Å⁻¹)	0.596

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.081, 0.250, 1.00
No. of reflections	2466
No. of parameters	208
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.63, −0.51
Computer programs: APEX2 and SAINT (Bruker, 2006 ), SHELXT (Sheldrick, 2015a ), SHELXL2018/3 (Sheldrick, 2015b ), SHELXTL (Sheldrick, 2008 ).

Supporting information

CCDC reference: 2163316

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S2056989022007885/yk2173sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989022007885/yk2173Isup2.hkl

checkCIF report

Computing details top

Data collection: SAINT (Bruker, 2006); cell refinement: SAINT (Bruker, 2006); data reduction: APEX2 (Bruker, 2006); program(s) used to solve structure: SHELXT (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2018/3 (Sheldrick, 2015b); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

4,4'-(Diazenediyl)dipyridinium nitrate perchlorate top

Crystal data top

C₁₀H₁₀N₄²⁺·NO₃⁻·ClO₄⁻	Z = 2
M_r = 347.68	F(000) = 356
Triclinic, P1	D_x = 1.622 Mg m⁻³
a = 8.3023 (8) Å	Mo Kα radiation, λ = 0.71073 Å
b = 10.0792 (9) Å	Cell parameters from 1709 reflections
c = 10.1052 (9) Å	θ = 2.3–25.3°
α = 116.966 (3)°	µ = 0.32 mm⁻¹
β = 105.481 (2)°	T = 298 K
γ = 92.871 (1)°	Block, red
V = 711.77 (11) Å³	0.45 × 0.40 × 0.33 mm

Data collection top

Bruker APEXII CCD diffractometer	1896 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube, Bruker (Mo) X-ray Source	R_int = 0.034
phi and ω continuous scans	θ_max = 25.1°, θ_min = 2.3°
Absorption correction: multi-scan (SADABS; Krause et al., 2015)	h = −9→9
T_min = 0.873, T_max = 0.904	k = −11→7
3625 measured reflections	l = −12→12
2466 independent reflections

Refinement top

Refinement on F²	0 restraints
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.081	H-atom parameters constrained
wR(F²) = 0.250	w = 1/[σ²(F_o²) + (0.189P)² + 0.2213P] where P = (F_o² + 2F_c²)/3
S = 1.00	(Δ/σ)_max < 0.001
2466 reflections	Δρ_max = 0.63 e Å⁻³
208 parameters	Δρ_min = −0.51 e Å⁻³

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
C1	0.2913 (7)	0.5983 (5)	0.6432 (5)	0.0737 (14)
H1A	0.305031	0.544442	0.545363	0.088*
C2	0.3896 (6)	0.7426 (5)	0.7501 (5)	0.0611 (11)
H2A	0.469672	0.786844	0.725164	0.073*
C3	0.3655 (5)	0.8180 (4)	0.8929 (4)	0.0494 (9)
C4	0.2457 (5)	0.7514 (5)	0.9279 (5)	0.0583 (10)
H4	0.228689	0.802795	1.024639	0.070*
C5	0.1525 (6)	0.6100 (6)	0.8199 (6)	0.0681 (13)
H5	0.071484	0.563924	0.842278	0.082*
C6	0.2190 (5)	0.0818 (4)	0.6583 (4)	0.0539 (10)
H6	0.201694	0.007099	0.555676	0.065*
C7	0.3250 (5)	0.2196 (5)	0.7198 (4)	0.0510 (9)
H7	0.377227	0.240802	0.658865	0.061*
C8	0.3518 (4)	0.3251 (4)	0.8734 (4)	0.0424 (8)
C9	0.2710 (5)	0.2956 (4)	0.9628 (4)	0.0465 (9)
H9	0.288421	0.367714	1.066539	0.056*
C10	0.1631 (5)	0.1558 (4)	0.8943 (5)	0.0513 (9)
H10	0.106801	0.132813	0.951752	0.062*
N1	0.1780 (6)	0.5378 (4)	0.6816 (5)	0.0723 (12)
H1B	0.118526	0.448315	0.614476	0.087*
N2	0.1408 (4)	0.0552 (3)	0.7461 (4)	0.0510 (8)
H2B	0.073137	−0.030783	0.704763	0.061*
N3	0.4662 (5)	0.9644 (4)	1.0220 (4)	0.0617 (9)
N4	0.4601 (4)	0.4702 (3)	0.9303 (3)	0.0464 (8)
N5	0.1514 (4)	0.2180 (4)	0.2959 (4)	0.0529 (8)
O1	0.0745 (4)	0.2327 (3)	0.3941 (3)	0.0592 (8)
O2	0.1175 (5)	0.0958 (4)	0.1741 (4)	0.0848 (11)
O3	0.2412 (6)	0.3270 (4)	0.3114 (4)	0.1011 (15)
Cl1	0.22108 (13)	0.71463 (11)	0.30697 (11)	0.0595 (4)
O4	0.0952 (4)	0.7204 (4)	0.3809 (4)	0.0798 (10)
O5	0.2642 (6)	0.8577 (4)	0.3160 (5)	0.1046 (14)
O6	0.3646 (6)	0.6719 (7)	0.3762 (7)	0.131 (2)
O7	0.1536 (7)	0.6059 (5)	0.1466 (5)	0.1112 (15)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.106 (4)	0.049 (3)	0.042 (2)	0.015 (3)	0.015 (2)	0.007 (2)
C2	0.072 (3)	0.045 (2)	0.057 (2)	0.004 (2)	0.026 (2)	0.0163 (19)
C3	0.047 (2)	0.0333 (18)	0.051 (2)	0.0021 (15)	0.0095 (16)	0.0102 (16)
C4	0.052 (2)	0.054 (2)	0.064 (2)	0.0061 (18)	0.0195 (18)	0.025 (2)
C5	0.054 (3)	0.056 (3)	0.091 (4)	−0.001 (2)	0.009 (2)	0.043 (3)
C6	0.058 (2)	0.041 (2)	0.0427 (19)	−0.0034 (17)	0.0141 (17)	0.0061 (16)
C7	0.048 (2)	0.048 (2)	0.050 (2)	−0.0002 (16)	0.0212 (16)	0.0161 (18)
C8	0.0385 (18)	0.0290 (16)	0.0469 (19)	0.0011 (13)	0.0086 (14)	0.0114 (15)
C9	0.051 (2)	0.0363 (18)	0.0387 (18)	0.0029 (15)	0.0151 (15)	0.0075 (15)
C10	0.055 (2)	0.044 (2)	0.057 (2)	0.0035 (17)	0.0230 (17)	0.0241 (18)
N1	0.076 (3)	0.0365 (18)	0.072 (3)	−0.0058 (17)	−0.013 (2)	0.0219 (19)
N2	0.0477 (18)	0.0341 (16)	0.0548 (18)	−0.0064 (13)	0.0102 (14)	0.0134 (15)
N3	0.074 (3)	0.050 (2)	0.057 (2)	0.0032 (17)	0.0302 (17)	0.0182 (17)
N4	0.0490 (18)	0.0371 (16)	0.0453 (15)	0.0039 (13)	0.0147 (13)	0.0144 (14)
N5	0.058 (2)	0.0440 (18)	0.0464 (17)	−0.0044 (15)	0.0227 (14)	0.0116 (15)
O1	0.0702 (19)	0.0487 (16)	0.0513 (15)	−0.0080 (13)	0.0297 (14)	0.0148 (13)
O2	0.122 (3)	0.0550 (19)	0.0581 (18)	−0.0123 (18)	0.0462 (19)	0.0060 (15)
O3	0.121 (3)	0.067 (2)	0.092 (3)	−0.031 (2)	0.065 (2)	0.0067 (19)
Cl1	0.0639 (7)	0.0527 (7)	0.0564 (7)	0.0023 (5)	0.0317 (5)	0.0162 (5)
O4	0.078 (2)	0.0570 (19)	0.092 (2)	−0.0099 (15)	0.0561 (19)	0.0123 (17)
O5	0.147 (4)	0.063 (2)	0.116 (3)	0.003 (2)	0.078 (3)	0.036 (2)
O6	0.087 (3)	0.209 (6)	0.172 (5)	0.040 (3)	0.057 (3)	0.145 (5)
O7	0.162 (4)	0.081 (3)	0.070 (2)	0.012 (3)	0.059 (3)	0.010 (2)

Geometric parameters (Å, º) top

C1—N1	1.326 (7)	C8—N4	1.452 (4)
C1—C2	1.391 (6)	C9—C10	1.388 (5)
C1—H1A	0.9300	C9—H9	0.9300
C2—C3	1.369 (6)	C10—N2	1.327 (5)
C2—H2A	0.9300	C10—H10	0.9300
C3—C4	1.379 (6)	N1—H1B	0.8600
C3—N3	1.458 (5)	N2—H2B	0.8600
C4—C5	1.360 (6)	N3—N3ⁱ	1.188 (7)
C4—H4	0.9300	N4—N4ⁱⁱ	1.216 (6)
C5—N1	1.334 (7)	N5—O3	1.219 (4)
C5—H5	0.9300	N5—O2	1.232 (4)
C6—N2	1.335 (5)	N5—O1	1.276 (4)
C6—C7	1.377 (6)	Cl1—O6	1.405 (5)
C6—H6	0.9300	Cl1—O7	1.408 (4)
C7—C8	1.373 (5)	Cl1—O5	1.424 (4)
C7—H7	0.9300	Cl1—O4	1.427 (3)
C8—C9	1.379 (5)

N1—C1—C2	119.7 (4)	C8—C9—C10	118.4 (3)
N1—C1—H1A	120.2	C8—C9—H9	120.8
C2—C1—H1A	120.2	C10—C9—H9	120.8
C3—C2—C1	118.3 (4)	N2—C10—C9	119.4 (3)
C3—C2—H2A	120.9	N2—C10—H10	120.3
C1—C2—H2A	120.9	C9—C10—H10	120.3
C2—C3—C4	120.2 (4)	C1—N1—C5	122.8 (4)
C2—C3—N3	125.2 (4)	C1—N1—H1B	118.6
C4—C3—N3	114.4 (3)	C5—N1—H1B	118.6
C5—C4—C3	119.4 (4)	C10—N2—C6	122.9 (3)
C5—C4—H4	120.3	C10—N2—H2B	118.6
C3—C4—H4	120.3	C6—N2—H2B	118.6
N1—C5—C4	119.6 (5)	N3ⁱ—N3—C3	112.2 (4)
N1—C5—H5	120.2	N4ⁱⁱ—N4—C8	112.6 (4)
C4—C5—H5	120.2	O3—N5—O2	119.4 (3)
N2—C6—C7	120.0 (3)	O3—N5—O1	121.1 (3)
N2—C6—H6	120.0	O2—N5—O1	118.9 (3)
C7—C6—H6	120.0	O6—Cl1—O7	108.4 (3)
C8—C7—C6	118.3 (4)	O6—Cl1—O5	111.8 (3)
C8—C7—H7	120.9	O7—Cl1—O5	107.3 (3)
C6—C7—H7	120.9	O6—Cl1—O4	110.1 (2)
C7—C8—C9	121.0 (3)	O7—Cl1—O4	109.5 (3)
C7—C8—N4	115.9 (3)	O5—Cl1—O4	109.7 (2)
C9—C8—N4	123.0 (3)

N1—C1—C2—C3	0.0 (7)	N4—C8—C9—C10	176.6 (3)
C1—C2—C3—C4	−0.4 (6)	C8—C9—C10—N2	0.0 (6)
C1—C2—C3—N3	175.1 (4)	C2—C1—N1—C5	0.3 (7)
C2—C3—C4—C5	0.4 (6)	C4—C5—N1—C1	−0.2 (7)
N3—C3—C4—C5	−175.6 (4)	C9—C10—N2—C6	0.4 (6)
C3—C4—C5—N1	−0.1 (6)	C7—C6—N2—C10	−1.5 (6)
N2—C6—C7—C8	2.2 (6)	C2—C3—N3—N3ⁱ	22.8 (7)
C6—C7—C8—C9	−1.8 (6)	C4—C3—N3—N3ⁱ	−161.4 (5)
C6—C7—C8—N4	−178.0 (3)	C7—C8—N4—N4ⁱⁱ	−149.2 (4)
C7—C8—C9—C10	0.7 (5)	C9—C8—N4—N4ⁱⁱ	34.8 (5)

Symmetry codes: (i) −x+1, −y+2, −z+2; (ii) −x+1, −y+1, −z+2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2B···O2ⁱⁱⁱ	0.86	2.47	3.046 (5)	125
N2—H2B···O1ⁱⁱⁱ	0.86	1.97	2.833 (4)	177
N2—H2B···N5ⁱⁱⁱ	0.86	2.58	3.372 (4)	153
N1—H1B···O4^iv	0.86	2.42	3.078 (5)	134
N1—H1B···O1	0.86	2.22	2.989 (5)	150
C10—H10···O2ⁱⁱⁱ	0.93	2.46	3.049 (5)	122
C10—H10···O2^v	0.93	2.42	3.257 (5)	150
C9—H9···O7^v	0.93	2.58	3.191 (6)	124
C7—H7···O6^vi	0.93	2.45	3.285 (6)	150
C6—H6···O5^vii	0.93	2.42	3.302 (6)	159
C6—H6···O4^vii	0.93	2.56	3.318 (5)	139
C6—H6···Cl1^vii	0.93	2.93	3.798 (4)	156
C5—H5···O7^iv	0.93	2.53	3.447 (7)	169
C1—H1A···O3	0.93	2.28	3.117 (5)	150

Symmetry codes: (iii) −x, −y, −z+1; (iv) −x, −y+1, −z+1; (v) x, y, z+1; (vi) −x+1, −y+1, −z+1; (vii) x, y−1, z.

Funding information

We gratefully acknowledge support by the Fundamental Research Funds for the Central Universities (grant No. 2–9–2021–008).

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