Crystal structures of 1,1′-bis­(carb­oxy­meth­yl)-4,4′-bipyridinium derivatives

Kumagai, H.; Kawata, S.; Ogihara, N.

doi:10.1107/S2056989024005127

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ISSN: 2056-9890

Volume 80| Part 7| July 2024| Pages 695-698

https://doi.org/10.1107/S2056989024005127

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Crystal structures of 1,1′-bis(carboxymethyl)-4,4′-bipyridinium derivatives

Hitoshi Kumagai,^a ^* Satoshi Kawata ^b and Nobuhiro Ogihara ^a

^a41-1 Yokomichi, Nagakute, Aichi 480-1192, Japan, and ^bNanakuma Jonan-ku, Fukuoka 814-0180, Japan
^*Correspondence e-mail: e1254@mosk.tytlabs.co.jp

Edited by T. Akitsu, Tokyo University of Science, Japan (Received 7 May 2024; accepted 30 May 2024; online 4 June 2024)

The crystal structures of 2-[1′-(carboxymethyl)-4,4′-bipyridine-1,1′-diium-1-yl]acetate tetrafluoroborate, C₁₄H₁₃N₂O₄⁺·BF₄⁻ or (Hbcbpy)(BF₄), and neutral 1,1′-bis(carboxylatomethyl)-4,4′-bipyridine-1,1′-diium (bcbpy), C₁₄H₂₀N₂O₈, are reported. The asymmetric unit of the (Hbcbpy)(BF₄) consists of a Hbcbpy⁺ monocation, a BF₄⁻ anion, and one-half of a water molecule. The BF₄⁻ anion is disordered. Two pyridinium rings of the Hbcbpy⁺ monocation are twisted at a torsion angle of 30.3 (2)° with respect to each other. The Hbcbpy monocation contains a carboxylic acid group and a deprotonated carboxylate group. Both groups exhibit both a long and a short C—O bond. The cations are linked by intermolecular hydrogen-bonding interactions between the carboxylic acid and the deprotonated carboxylate group to give one-dimensional zigzag chains. The asymmetric unit of the neutral bcbpy consists of one-half of the bcbpy and two water molecules. In contrast to the Hbcbpy⁺ monocation, the neutral bcbpy molecule contains two pyridinium rings that are coplanar with each other and a carboxylate group with similar C—O bond lengths. The molecules are connected by intermolecular hydrogen-bonding interactions between water molecules and carboxylate groups, forming a three-dimensional hydrogen-bonding network.

Keywords: crystal structure; hydrogen bonding; viologen.

CCDC references: 2359279; 2359278

1. Chemical context

Viologen derivatives (N,N′-disubstituted bipyridinium salts) have been widely researched because of their reversible electroactivity, good photochromic properties, and high biochemical activity. Because of these interesting physical and chemical properties, the synthesis of organic polymers or metal–organic frameworks by assembling viologen derivatives using covalent bonds or coordination bonds is attracting attention (Jouhara et al., 2019 ; Madasamy et al., 2019 ; Sun & Zhang, 2015 ). Non-covalent interactions such as hydrogen-bonding and electrostatic interactions have been used to assemble functional molecules in the field of crystal engineering (Desiraju, 2001 ; Horiuchi et al., 2007 ; Lehn, 1995 ). We have been working on hydrogen-bonded assemblies to synthesize functional materials and have previously reported hydrogen-bonded assemblies in which functional molecules such as redox-active ferrocene derivatives or tetrathiafulvalene are used (Kitagawa & Kawata, 2002 ; Nagayoshi et al., 2003 ). In the present study, we focus on hydrogen-bonded assemblies of N,N′-bis(2-carboxyethyl)-4,4′-bipyridinium derivatives.

2. Structural commentary

The asymmetric unit of (Hbcbpy)(BF₄) consists of a Hbcbpy⁺ monocation, a BF₄⁻ anion, and one-half of a water molecule (Fig. 1). The BF₄⁻ anion is disordered. The key feature of the structure is a hydrogen-bonded one-dimensional chain structure in which the chains are connected by intermolecular –COO⁻⋯HOOC– hydrogen-bonding interactions (Table 1, Fig. 2). Because the water molecules of (Hbcbpy)(BF₄) are not involved in the hydrogen-bonding interactions, water molecules are easily lost from the crystal to give partial occupancy. Two pyridinium groups of the Hbcbpy⁺ monocation are twisted at a C4—C5—C8—C9 torsion angle of 30.3 (2)° [dihedral angle between the rings = 30.18 (8)°] to each other. The carboxymethyl groups bonded to the pyridinium groups exhibit a bent structure and are nearly perpendicular to the pyridinium groups. The Hbcbpy⁺ monocation contains a carboxylic acid group, –COOH, and a deprotonated negatively charged carboxylate group, –COO⁻, at each end of the monocation. The charge is compensated by a BF₄⁻ anion. The C—O and C=O bond lengths in the carboxylic acid group, C1—O1 and C1—O2, are 1.294 (2) and 1.223 (2) Å, respectively, with a difference of 0.071 (2) Å. Although the carboxylate group is deprotonated, C14—O3 and C14—O4 also show two different bond lengths of 1.235 (2) and 1.287 (2) Å, respectively, where the difference is 0.052 (2) Å. The carboxylic acid group acts as a hydrogen-bond donor, and O4 of the deprotonated carboxylate groups acts as a hydrogen-bond acceptor; the C14—O4 bond is longer than the C14—O3 bond. No hydrogen-bonding interactions are found for O3. The corresponding ClO₄⁻ salt also exhibits two different C—O bond lengths in the deprotonated carboxylate group and similar hydrogen-bonding interactions to give a zigzag chain structure (Gutov et al., 2008 ). While the measurements of the (Hbcbpy)(BF₄) were conducted at 100 K, the hydrogen-bonding distances of O(carboxylic acid)⋯O(carboxylate) is very similar to that of the ClO₄ salt measured at room temperature, indicative of a small influence of thermal libration (Gutov et al., 2008). We assume that the different C—O bond lengths in the carboxylate group arise from intermolecular hydrogen-bonding interactions.

Table 1
Hydrogen-bond geometry (Å, °) for (Hbcbpy)(BF₄)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1B⋯O4ⁱ	1.05	1.42	2.4694 (18)	172.0
Symmetry code: (i) $[x-{\script{9\over 2}}, -y-{\script{7\over 2}}, z-{\script{7\over 2}}]$ .

Figure 1
Structure of (Hbcbpy)(BF₄) with labeling scheme and 50% probability displacement ellipsoids.

Figure 2
View of the hydrogen-bonded zigzag chain structure of Hbcbpy⁺ monocations. Dashed lines represent hydrogen bonds between oxygen atoms of Hbcbpy⁺ monocations. Only the carboxylic hydrogen atoms are shown for clarity. [Symmetry code: (i) x − $[{9\over 2}]$ , −y − $[{7\over 2}]$ , z − $[{7\over 2}]$ .]

The asymmetric unit of bcbpy consists of one-half of the neutral bcbpy molecule and two solvent water molecules (Fig. 3). The key feature of the structure is a hydrogen-bonded three-dimensional network in which the molecules are connected by intermolecular hydrogen bonding interactions between bcbpy and water molecules (Table 2, Fig. 4). In the bcbpy molecule, two negatively charged deprotonated carboxylate groups are attached to the pyridinium groups to give a neutral molecule. The carboxymethyl group bonded to the pyridinium group exhibits a structure similar to that of a Hbcbpy⁺ monocation. Two C—O bonds in the carboxylate group form similar hydrogen-bonding interactions between water molecules. Two differences are observed between the structure of the bcbpy molecule and that of the Hbcbpy⁺ monocation. The first difference is the arrangement of the two pyridinium groups. Although the two pyridinium groups are twisted toward each other in the Hbcbpy⁺ monocation, they are coplanar with each other in the neutral bcbpy molecule, with a C6—C5—C5ⁱ—C4ⁱ torsion angle of 0.31 (14)°. The other difference is the C—O bond lengths in the deprotonated carboxylate group. In the neutral bcbpy molecule, the two C—O bond lengths are similar [1.248 (1) and 1.255 (1) Å, and the difference [0.007 (1) Å] is smaller than that between the C—O bond lengths in the deprotonated carboxylate group in the Hbcbpy⁺ monocation. Both C—O bonds in the carboxylate group undergo similar hydrogen-bonding interactions between water molecules (Fig. 4). A neutral bcbpy molecule without coordination bonds has been reported in [Zn(H₂O)₆]·(bcbpy)·(1,4-benzen dicarboxylate)·3H₂O (Zhao & Liu, 2021 ). The bcbpy molecule in this Zn compound contains two types of carboxylate groups. One carboxylate group shows hydrogen-bonding interactions similar to those observed in our structure; the two C—O bond lengths in the carboxylate group are 1.236 (3) and 1.249 (3) Å, differing by 0.013 (3) Å. The other carboxylate group in the Zn compound exhibits two types of hydrogen-bonding interactions: interactions with three water molecules, and an interaction with one water molecule. The two C—O bond lengths in the carboxylate group are 1.235 (3) and 1.259 (3) Å; thus, the difference between the C—O bond lengths [0.024 (3) Å] is slightly larger than the corresponding difference for the first carboxylate group. These results indicate that the difference between the two C—O bond lengths in the carboxylate group is influenced by the type of hydrogen-bonding interactions in the bcbpy system.

Table 2
Hydrogen-bond geometry (Å, °) for bcbpy

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O3—H9⋯O2	0.859 (19)	1.96 (2)	2.8135 (12)	172.1 (19)
O3—H8⋯O1ⁱ	0.85 (2)	1.95 (2)	2.7888 (11)	171 (2)
O4—H10⋯O2	0.89 (2)	1.97 (2)	2.8233 (12)	158.9 (18)
O4—H11⋯O1ⁱⁱ	0.85 (2)	1.97 (2)	2.8007 (13)	164.1 (17)
Symmetry codes: (i) $[x+{\script{1\over 2}}, -y+{\script{3\over 2}}, z+{\script{1\over 2}}]$ ; (ii) $[x-{\script{1\over 2}}, -y+{\script{3\over 2}}, z+{\script{1\over 2}}]$ .

Figure 3
Structure of bcbpy with labeling scheme and 50% probability displacement ellipsoids. [Symmetry code: (i) x + $[{1\over 2}]$ , −y + $[{3\over 2}]$ , z + $[{1\over 2}]$ ]

Figure 4
View of hydrogen-bonded network of bcbpy molecules and water molecules. Dashed lines represent hydrogen bonds between oxygen atoms. Hydrogen atoms of bcbpy are omitted for clarity. Only the hydrogen atoms of the water molecules are shown for clarity. [Symmetry codes: (i) x + $[{1\over 2}]$ , −y + $[{3\over 2}]$ , z + $[{1\over 2}]$ ; (ii) x − $[{1\over 2}]$ , −y + $[{3\over 2}]$ , z + $[{1\over 2}]$ .]

3. Supramolecular features

The Hbcbpy⁺ monocation contains a carboxylic acid and a deprotonated carboxylate group at each end of the monocation. Intermolecular hydrogen-bonding interactions occur between the carboxylic acid of one cation and the negatively charged carboxylate groups of another monocation to give one-dimensional chains (Table 1, Fig. 2). The chains zigzag because of the bent structure of the carboxymethyl groups attached to the pyridinium groups. Within the chains, the pyridinium rings are not coplanar, exhibiting no π–π stacking interactions.

The bcbpy molecule contains two deprotonated carboxylate groups at its ends. The negatively charged carboxylate groups undergo intermolecular hydrogen-bonding interactions between water molecules (Table 2). The negatively charged carboxylate groups act as hydrogen-bond acceptors, and water molecules act as hydrogen-bond donors. The water molecule bridges two bcbpy molecules by hydrogen-bonding interactions, forming a three-dimensional hydrogen bonding network. Although the two pyridinium groups are coplanar, no π–π stacking interactions are observed.

Both compounds lack π–π stacking interactions. A possible explanation for this is that the carboxymethyl groups bonded to the pyridinium groups, which are bent and nearly perpendicular to the pyridinium groups, prevent stacking interactions. Thus, the supramolecular structures of the Hbcbpy⁺ monocation and bcbpy molecule are primarily stabilized by the hydrogen-bonding interactions between negatively charged carboxylate groups and carboxylic acids or water molecules.

4. Database survey

A survey of the Cambridge Structural Database (CSD, v5.44, April 2023; Groom et al., 2016 ) for structures with a bcbpy moiety resulted in nine matches. Of these, (Hbcbpy)(ClO₄) (ODOQUV; Zhao & Liu, 2021) and (Zn(H₂O)₆)(bcbpy)(1,4-benzene dicarboxylate) (AXEJEV; Gutov et al., 2008) are related to the present work. Other compounds exhibit metal coordination and contain co-bridging ligands such as tricarboxylate or hexacyano metallate ions to compensate charges (Li et al., 2020 ; Liu et al., 2020 ; Ma et al., 2009 , 2011 ). The crystal structures of similar viologens in which carboxyethyl groups are attached to nitrogen atoms have been reported, viz. 3-[1′-(2-carboxyethyl)-4,4′-bipyridinium-1-yl]propanoate perchlorate (ODOQOP; Gutov et al., 2008) and catena-[tris[1,1′-bis(2-carboxyethyl)-4,4′-bipyridinium]hexakis(μ-bromo)tribromotrilead(II) dihydrate] (FEBLOQ; Sun et al., 2017 ). ODOQOP is a monocation similar to ODOQUV. FEBLOQ is a dication in which [Pb₃Br₉]_n³ⁿ⁻ chains act as counter-ions in the crystal. (4-{2-[1-(Carboxymethyl)pyridin-1-ium-4-yl]ethenyl}pyridin-1-ium-1-yl)acetate tetrafluoroborate (MUPBUX), (4-{2-[1-(carboxymethyl)pyridin-1-ium-4-yl]ethenyl}pyridin-1-ium-1-yl)acetate perchlorate (MUPCAE), and tris(aqua)-[1-(carboxymethyl)-4-(2-{1-[(carboxy)methyl]pyridin-1-ium-4-yl}ethenyl)pyridin-1-iumato]lithium iodide dihydrate (MUPCEI) are ethylenic derivatives in which two pyridinium groups are linked by an ethylene group (Jouhara et al., 2019). MUPBUX and MUPCAE are monocations similar to the Hbcbpy⁺ monocation.

5. Synthesis and crystallization

The dibromo salt H₂bcbpy(Br)₂ was synthesized using a modified version of a reported procedure (Fajardo & Lewis, 1997 ). The route is presented in the supporting information (scheme S1). (Hbcbpy)(BF₄) and bcbpy were obtained as follows. An aqueous solution (50 mL) of Li(BF₄) (38.6 g, 320 mmol) was added to an aqueous solution (50 mL) of H₂bcbpy(Br)₂ (20.0 g, 40 mmol). The mixture was stirred, the resultant white precipitate was collected by filtration, and the obtained solution was slowly evaporated to yield colorless crystals of (Hbcbpy)(BF₄). The crystals (4.9 g, 11 mmol) were dissolved in 30 mL of distilled water, and an aqueous solution (20 mL) of LiOH (0.42 g, 18 mmol) was added. The resultant solution was evaporated, and the obtained white precipitate was filtered. Colorless crystals began to form from the obtained solution at ambient temperature. One of these crystals was used for X-ray crystallographic analysis.

6. Refinement

The crystal data, data collection, and structure refinement details are summarized in Table 3. The hydrogen atoms of the carboxylic acid and water molecules, which are involved in hydrogen-bonding interactions were located in difference-Fourier maps and refined isotropically. Other hydrogen atoms were placed in idealized positions and refined using a riding model. The occupancy of the water molecule in (Hbcbpy)(BF₄) was refined.

Table 3
Experimental details

	(Hbcbpy)(BF₄)	bcbpy
Crystal data
Chemical formula	C₁₄H₁₃N₂O_4.5⁺·BF₄⁻	C₁₄H₂₀N₂O₈
M_r	368.08	344.32
Crystal system, space group	Monoclinic, P2₁/n	Monoclinic, P2₁/n
Temperature (K)	100	296
a, b, c (Å)	7.6794 (16), 20.987 (4), 10.0514 (19)	6.2521 (2), 11.4122 (4), 11.1413 (4)
β (°)	95.123 (3)	99.4832 (14)
V (Å³)	1613.5 (5)	784.07 (5)
Z	4	2
Radiation type	Mo Kα	Mo Kα
μ (mm⁻¹)	0.14	0.12
Crystal size (mm)	0.60 × 0.40 × 0.40	0.48 × 0.46 × 0.42

Data collection
Diffractometer	Rigaku R-AXIS RAPID	Rigaku R-AXIS RAPID
Absorption correction	Multi-scan (ABSCOR; Rigaku, 1995 )	Multi-scan (ABSCOR; Rigaku, 1995)
T_min, T_max	0.656, 0.987	0.788, 0.951
No. of measured, independent and observed reflections	15631, 3652, 3119 [I > 2σ(I)]	7476, 1793, 1678 [F² > 2.0σ(F²)]
R_int	0.032	0.022
(sin θ/λ)_max (Å⁻¹)	0.648	0.649

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.051, 0.132, 1.05	0.048, 0.123, 1.11
No. of reflections	3652	1793
No. of parameters	292	125
No. of restraints	1	0
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.72, −0.56	0.40, −0.28
Computer programs: RAPID-AUTO (Rigaku, 1995), Il Milione (Burla et al., 2007 ), SUPERFLIP (Palatinus & Chapuis, 2007 ), SHELXL2018/3 (Sheldrick, 2015 ), Yadokari-XG 2009 (Kabuto et al., 2009 ) and CrystalStructure (Rigaku, 2019 ).

Supporting information

CCDC references: 2359279; 2359278

Crystal structure: contains datablocks global, HbcbpyBF4, bcbpy. DOI: https://doi.org/10.1107/S2056989024005127/jp2007sup1.cif

Structure factors: contains datablock bcbpy. DOI: https://doi.org/10.1107/S2056989024005127/jp2007bcbpysup2.hkl

Structure factors: contains datablock HbcbpyBF4. DOI: https://doi.org/10.1107/S2056989024005127/jp2007HbcbpyBF4sup3.hkl

Supporting information file. DOI: https://doi.org/10.1107/S2056989024005127/jp2007bcbpysup4.cdx

Supporting information file. DOI: https://doi.org/10.1107/S2056989024005127/jp2007HbcbpyBF4sup5.cdx

checkCIF report

Computing details top

1,1'-Bis(carboxylatomethyl)-4,4'-bipyridine-1,1'-diium (bcbpy) top

Crystal data top

C₁₄H₂₀N₂O₈	F(000) = 364.00
M_r = 344.32	D_x = 1.458 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71075 Å
a = 6.2521 (2) Å	Cell parameters from 7055 reflections
b = 11.4122 (4) Å	θ = 3.3–27.5°
c = 11.1413 (4) Å	µ = 0.12 mm⁻¹
β = 99.4832 (14)°	T = 296 K
V = 784.07 (5) Å³	Block, yellow
Z = 2	0.48 × 0.46 × 0.42 mm

Data collection top

Rigaku R-AXIS RAPID diffractometer	1678 reflections with F² > 2.0σ(F²)
Detector resolution: 10.000 pixels mm^-1	R_int = 0.022
ω scans	θ_max = 27.5°, θ_min = 3.5°
Absorption correction: multi-scan (ABSCOR; Rigaku, 1995)	h = −8→7
T_min = 0.788, T_max = 0.951	k = −14→14
7476 measured reflections	l = −14→14
1793 independent reflections

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.048	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.123	H atoms treated by a mixture of independent and constrained refinement
S = 1.11	w = 1/[σ²(F_o²) + (0.0813P)² + 0.1761P] where P = (F_o² + 2F_c²)/3
1793 reflections	(Δ/σ)_max < 0.001
125 parameters	Δρ_max = 0.40 e Å⁻³
0 restraints	Δρ_min = −0.28 e Å⁻³
Primary atom site location: structure-invariant direct methods

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.

Refinement. Refinement was performed using all reflections. The weighted R-factor (wR) and goodness of fit (S) are based on F². R-factor (gt) are based on F. The threshold expression of F² > 2.0 sigma(F²) is used only for calculating R-factor (gt).

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

	x	y	z	U_iso*/U_eq
O1	0.51613 (14)	0.68508 (8)	0.03041 (7)	0.0252 (2)
O2	0.48570 (13)	0.70887 (7)	0.22699 (7)	0.0228 (2)
O3	0.80684 (15)	0.87902 (8)	0.29910 (8)	0.0270 (2)
O4	0.41417 (14)	0.74797 (8)	0.46745 (8)	0.0277 (2)
N1	0.17838 (14)	0.54278 (8)	0.22070 (8)	0.0176 (2)
C7	0.28870 (17)	0.46929 (10)	0.30354 (10)	0.0207 (3)
H7	0.411238	0.430906	0.286205	0.025*
C6	0.22108 (18)	0.45072 (9)	0.41363 (10)	0.0204 (3)
H6	0.297168	0.399296	0.469856	0.025*
C5	0.03839 (16)	0.50899 (9)	0.44103 (9)	0.0165 (3)
C4	−0.07103 (17)	0.58473 (10)	0.35318 (9)	0.0194 (3)
H4	−0.193261	0.624817	0.368421	0.023*
C3	0.00173 (17)	0.60021 (10)	0.24390 (10)	0.0199 (3)
H3	−0.071887	0.650736	0.185822	0.024*
C2	0.26195 (17)	0.56648 (10)	0.10675 (9)	0.0195 (3)
H2A	0.143316	0.591106	0.044479	0.023*
H2B	0.322475	0.495057	0.079110	0.023*
C1	0.43789 (17)	0.66260 (9)	0.12460 (9)	0.0183 (2)
H9	0.709 (3)	0.8291 (18)	0.2700 (17)	0.041 (5)*
H8	0.860 (3)	0.8538 (18)	0.369 (2)	0.049 (5)*
H10	0.400 (3)	0.7365 (16)	0.387 (2)	0.041 (5)*
H11	0.285 (3)	0.7551 (15)	0.4820 (18)	0.043 (5)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0241 (4)	0.0337 (5)	0.0190 (4)	−0.0043 (3)	0.0071 (3)	0.0034 (3)
O2	0.0228 (4)	0.0264 (4)	0.0193 (4)	−0.0036 (3)	0.0037 (3)	−0.0010 (3)
O3	0.0265 (5)	0.0282 (5)	0.0259 (5)	−0.0060 (3)	0.0033 (3)	0.0055 (3)
O4	0.0210 (5)	0.0380 (5)	0.0241 (5)	0.0000 (3)	0.0041 (3)	−0.0065 (4)
N1	0.0185 (5)	0.0185 (4)	0.0162 (4)	−0.0025 (3)	0.0045 (3)	0.0000 (3)
C7	0.0206 (5)	0.0204 (5)	0.0221 (5)	0.0028 (4)	0.0067 (4)	0.0023 (4)
C6	0.0215 (5)	0.0198 (5)	0.0209 (5)	0.0032 (4)	0.0059 (4)	0.0039 (4)
C5	0.0173 (5)	0.0155 (5)	0.0171 (5)	−0.0023 (4)	0.0037 (4)	−0.0004 (4)
C4	0.0180 (5)	0.0212 (5)	0.0193 (5)	0.0016 (4)	0.0045 (4)	0.0013 (4)
C3	0.0191 (5)	0.0219 (5)	0.0186 (5)	0.0016 (4)	0.0029 (4)	0.0025 (4)
C2	0.0214 (5)	0.0230 (5)	0.0151 (5)	−0.0017 (4)	0.0058 (4)	−0.0003 (4)
C1	0.0162 (5)	0.0209 (5)	0.0182 (5)	0.0013 (4)	0.0035 (4)	0.0026 (4)

Geometric parameters (Å, º) top

O1—C1	1.2553 (13)	C6—C5	1.3982 (14)
O2—C1	1.2479 (14)	C6—H6	0.9300
O3—H9	0.86 (2)	C5—C4	1.3973 (15)
O3—H8	0.85 (2)	C5—C5ⁱ	1.4856 (19)
O4—H10	0.89 (2)	C4—C3	1.3794 (14)
O4—H11	0.85 (2)	C4—H4	0.9300
N1—C3	1.3454 (14)	C3—H3	0.9300
N1—C7	1.3495 (15)	C2—C1	1.5429 (15)
N1—C2	1.4753 (13)	C2—H2A	0.9700
C7—C6	1.3780 (14)	C2—H2B	0.9700
C7—H7	0.9300

H9—O3—H8	105.7 (19)	C3—C4—H4	119.9
H10—O4—H11	105.3 (18)	C5—C4—H4	119.9
C3—N1—C7	120.97 (9)	N1—C3—C4	120.51 (10)
C3—N1—C2	119.62 (9)	N1—C3—H3	119.7
C7—N1—C2	119.27 (9)	C4—C3—H3	119.7
N1—C7—C6	120.47 (10)	N1—C2—C1	111.44 (8)
N1—C7—H7	119.8	N1—C2—H2A	109.3
C6—C7—H7	119.8	C1—C2—H2A	109.3
C7—C6—C5	120.17 (10)	N1—C2—H2B	109.3
C7—C6—H6	119.9	C1—C2—H2B	109.3
C5—C6—H6	119.9	H2A—C2—H2B	108.0
C4—C5—C6	117.68 (9)	O2—C1—O1	127.60 (10)
C4—C5—C5ⁱ	120.85 (11)	O2—C1—C2	118.49 (9)
C6—C5—C5ⁱ	121.47 (12)	O1—C1—C2	113.91 (9)
C3—C4—C5	120.19 (10)

C3—N1—C7—C6	0.60 (17)	C7—N1—C3—C4	−0.25 (16)
C2—N1—C7—C6	176.33 (10)	C2—N1—C3—C4	−175.96 (10)
N1—C7—C6—C5	−0.68 (17)	C5—C4—C3—N1	−0.02 (17)
C7—C6—C5—C4	0.41 (16)	C3—N1—C2—C1	92.74 (11)
C7—C6—C5—C5ⁱ	−179.89 (11)	C7—N1—C2—C1	−83.05 (12)
C6—C5—C4—C3	−0.07 (16)	N1—C2—C1—O2	−1.12 (14)
C5ⁱ—C5—C4—C3	−179.76 (11)	N1—C2—C1—O1	179.23 (9)

Symmetry code: (i) −x, −y+1, −z+1.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O3—H9···O2	0.859 (19)	1.96 (2)	2.8135 (12)	172.1 (19)
O3—H8···O1ⁱⁱ	0.85 (2)	1.95 (2)	2.7888 (11)	171 (2)
O4—H10···O2	0.89 (2)	1.97 (2)	2.8233 (12)	158.9 (18)
O4—H11···O1ⁱⁱⁱ	0.85 (2)	1.97 (2)	2.8007 (13)	164.1 (17)

Symmetry codes: (ii) x+1/2, −y+3/2, z+1/2; (iii) x−1/2, −y+3/2, z+1/2.

2-[1'-(Carboxymethyl)-4,4'-bipyridine-1,1'-diium-1-yl]acetate tetrafluoroborate (HbcbpyBF4) top

Crystal data top

C₁₄H₁₃N₂O_4.5⁺·BF₄⁻	F(000) = 756
M_r = 368.08	D_x = 1.519 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71075 Å
a = 7.6794 (16) Å	Cell parameters from 2543 reflections
b = 20.987 (4) Å	θ = 5.6–27.4°
c = 10.0514 (19) Å	µ = 0.14 mm⁻¹
β = 95.123 (3)°	T = 100 K
V = 1613.5 (5) Å³	Platelet, colorless
Z = 4	0.60 × 0.40 × 0.40 mm

Data collection top

Rigaku R-AXIS RAPID diffractometer	3119 reflections with I > 2σ(I)
Detector resolution: 10.000 pixels mm^-1	R_int = 0.032
ω scans	θ_max = 27.4°, θ_min = 3.2°
Absorption correction: multi-scan (ABSCOR; Rigaku, 1995)	h = −9→9
T_min = 0.656, T_max = 0.987	k = −27→27
15631 measured reflections	l = −13→13
3652 independent 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)] = 0.051	Hydrogen site location: mixed
wR(F²) = 0.132	H atoms treated by a mixture of independent and constrained refinement
S = 1.05	w = 1/[σ²(F_o²) + (0.0594P)² + 1.2013P] where P = (F_o² + 2F_c²)/3
3652 reflections	(Δ/σ)_max < 0.001
292 parameters	Δρ_max = 0.72 e Å⁻³
1 restraint	Δρ_min = −0.56 e Å⁻³

Special details top

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

	x	y	z	U_iso*/U_eq	Occ. (<1)
O4	−0.12434 (15)	0.59508 (5)	0.51560 (12)	0.0246 (3)
O3	−0.18392 (15)	0.49606 (6)	0.58466 (13)	0.0278 (3)
C14	−0.0977 (2)	0.54581 (7)	0.59083 (16)	0.0212 (3)
C13	0.0546 (2)	0.54866 (8)	0.69960 (17)	0.0232 (3)
H13	0.006964	0.550938	0.787824	0.028*
H13A	0.123093	0.508798	0.697034	0.028*
N2	0.17293 (17)	0.60349 (6)	0.68628 (13)	0.0206 (3)
C10	0.3334 (2)	0.59435 (8)	0.64492 (17)	0.0224 (3)
H10	0.368960	0.552814	0.621280	0.027*
C9	0.4466 (2)	0.64527 (8)	0.63679 (17)	0.0233 (3)
H9	0.559646	0.638678	0.607859	0.028*
C8	0.3941 (2)	0.70639 (8)	0.67125 (16)	0.0211 (3)
C5	0.5167 (2)	0.76126 (8)	0.67427 (16)	0.0221 (3)
N1	0.75008 (18)	0.86160 (6)	0.68917 (14)	0.0227 (3)
C12	0.2245 (2)	0.71446 (8)	0.70921 (17)	0.0249 (4)
H12	0.183872	0.755753	0.729713	0.030*
C7	0.6207 (2)	0.86054 (8)	0.77144 (18)	0.0252 (3)
H7	0.611023	0.894042	0.833916	0.030*
C1	1.0355 (2)	0.88901 (7)	0.80414 (16)	0.0208 (3)
O1	1.14297 (16)	0.93451 (6)	0.84102 (13)	0.0305 (3)
O2	1.04698 (15)	0.83348 (5)	0.84064 (12)	0.0240 (3)
C11	0.1169 (2)	0.66241 (8)	0.71677 (17)	0.0246 (3)
H11	0.002372	0.667885	0.743615	0.029*
C6	0.5025 (2)	0.81110 (8)	0.76520 (17)	0.0250 (3)
H6	0.410968	0.810802	0.822826	0.030*
C2	0.8844 (2)	0.91214 (8)	0.70692 (18)	0.0246 (3)
H2	0.832748	0.951166	0.742328	0.029*
H2A	0.927993	0.922573	0.619744	0.029*
F1A	0.2612 (3)	0.83677 (18)	0.3422 (3)	0.0623 (9)	0.662 (3)
C4	0.6512 (2)	0.76409 (8)	0.58975 (17)	0.0272 (4)
H4	0.663465	0.731336	0.526009	0.033*
F2A	0.1745 (3)	0.84329 (14)	0.5476 (2)	0.0524 (7)	0.662 (3)
C3	0.7663 (2)	0.81476 (9)	0.59933 (18)	0.0283 (4)
H3	0.858056	0.816631	0.541966	0.034*
B1A	0.2445 (7)	0.8769 (2)	0.4484 (4)	0.0336 (9)	0.662 (3)
F3A	0.4096 (3)	0.89999 (11)	0.4970 (2)	0.0540 (7)	0.662 (3)
F4A	0.1333 (5)	0.92664 (13)	0.4093 (3)	0.0938 (13)	0.662 (3)
B1B	0.1633 (13)	0.8772 (5)	0.4399 (9)	0.037 (2)	0.338 (3)
H1B	−0.259900	0.581900	0.413100	0.050*
F1B	0.2530 (6)	0.9024 (3)	0.5528 (4)	0.0615 (15)	0.338 (3)
F2B	0.2596 (6)	0.8794 (4)	0.3323 (4)	0.0537 (15)	0.338 (3)
F3B	0.1320 (8)	0.8129 (3)	0.4697 (7)	0.0718 (17)	0.338 (3)
F4B	0.0007 (6)	0.9038 (2)	0.4137 (3)	0.0508 (13)	0.338 (3)
O5B	0.5838 (6)	0.9583 (2)	0.5161 (4)	0.0446 (11)	0.352 (2)
O5A	−0.1551 (12)	0.9609 (5)	0.4223 (9)	0.036 (2)	0.148 (2)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O4	0.0198 (6)	0.0195 (6)	0.0340 (6)	−0.0016 (4)	−0.0005 (5)	0.0036 (5)
O3	0.0219 (6)	0.0218 (6)	0.0396 (7)	−0.0056 (5)	0.0020 (5)	0.0037 (5)
C14	0.0158 (7)	0.0200 (7)	0.0285 (8)	−0.0005 (6)	0.0057 (6)	−0.0001 (6)
C13	0.0203 (8)	0.0192 (7)	0.0303 (8)	−0.0010 (6)	0.0034 (6)	0.0037 (6)
N2	0.0172 (6)	0.0193 (6)	0.0251 (7)	−0.0003 (5)	0.0008 (5)	−0.0002 (5)
C10	0.0166 (7)	0.0206 (7)	0.0297 (8)	0.0028 (6)	0.0005 (6)	−0.0042 (6)
C9	0.0168 (7)	0.0238 (8)	0.0294 (8)	0.0001 (6)	0.0024 (6)	−0.0057 (6)
C8	0.0192 (7)	0.0204 (8)	0.0236 (7)	−0.0014 (6)	0.0002 (6)	−0.0026 (6)
C5	0.0183 (7)	0.0201 (7)	0.0273 (8)	−0.0001 (6)	−0.0016 (6)	−0.0016 (6)
N1	0.0200 (7)	0.0181 (6)	0.0294 (7)	−0.0015 (5)	−0.0019 (5)	−0.0004 (5)
C12	0.0213 (8)	0.0194 (8)	0.0339 (9)	0.0018 (6)	0.0022 (6)	−0.0047 (7)
C7	0.0216 (8)	0.0204 (8)	0.0330 (9)	0.0016 (6)	0.0005 (6)	−0.0059 (7)
C1	0.0185 (7)	0.0186 (7)	0.0260 (8)	−0.0003 (6)	0.0053 (6)	−0.0016 (6)
O1	0.0262 (6)	0.0195 (6)	0.0438 (7)	−0.0050 (5)	−0.0087 (5)	0.0016 (5)
O2	0.0231 (6)	0.0179 (6)	0.0311 (6)	−0.0008 (4)	0.0021 (5)	0.0012 (5)
C11	0.0190 (8)	0.0229 (8)	0.0322 (8)	0.0025 (6)	0.0046 (6)	−0.0045 (7)
C6	0.0198 (8)	0.0229 (8)	0.0325 (9)	0.0007 (6)	0.0041 (6)	−0.0048 (7)
C2	0.0216 (8)	0.0176 (7)	0.0338 (9)	−0.0031 (6)	−0.0011 (6)	0.0010 (6)
F1A	0.0304 (11)	0.099 (2)	0.0589 (15)	−0.0085 (14)	0.0125 (10)	−0.0396 (17)
C4	0.0267 (9)	0.0260 (8)	0.0291 (8)	−0.0052 (7)	0.0044 (7)	−0.0081 (7)
F2A	0.0353 (11)	0.0829 (18)	0.0405 (11)	−0.0104 (11)	0.0127 (9)	0.0096 (12)
C3	0.0265 (9)	0.0294 (9)	0.0294 (9)	−0.0051 (7)	0.0054 (7)	−0.0055 (7)
B1A	0.034 (2)	0.0352 (19)	0.032 (2)	0.000 (2)	0.007 (2)	0.0040 (14)
F3A	0.0532 (13)	0.0619 (14)	0.0449 (11)	−0.0261 (10)	−0.0073 (9)	0.0120 (10)
F4A	0.122 (3)	0.0458 (15)	0.103 (2)	0.0258 (17)	−0.054 (2)	0.0037 (14)
B1B	0.028 (4)	0.058 (5)	0.026 (4)	−0.009 (5)	0.011 (4)	−0.004 (3)
F1B	0.049 (3)	0.100 (4)	0.034 (2)	0.000 (2)	−0.0034 (17)	−0.020 (2)
F2B	0.033 (2)	0.103 (4)	0.0269 (19)	−0.027 (3)	0.0100 (15)	−0.006 (3)
F3B	0.075 (4)	0.059 (3)	0.085 (4)	−0.002 (3)	0.026 (3)	0.021 (3)
F4B	0.038 (2)	0.091 (3)	0.0237 (17)	0.009 (2)	0.0002 (14)	−0.0136 (18)
O5B	0.050 (3)	0.041 (2)	0.041 (2)	−0.004 (2)	−0.0052 (19)	0.0051 (19)
O5A	0.040 (5)	0.037 (5)	0.030 (4)	−0.001 (4)	0.000 (4)	0.002 (4)

Geometric parameters (Å, º) top

O4—C14	1.287 (2)	C12—H12	0.9500
O4—H1B	1.4248	C7—C6	1.376 (2)
O3—C14	1.2350 (19)	C7—H7	0.9500
C14—C13	1.529 (2)	C1—O2	1.2226 (19)
C13—N2	1.480 (2)	C1—O1	1.2944 (19)
C13—H13	0.9900	C1—C2	1.528 (2)
C13—H13A	0.9900	C11—H11	0.9500
N2—C10	1.349 (2)	C6—H6	0.9500
N2—C11	1.353 (2)	C2—H2	0.9900
C10—C9	1.384 (2)	C2—H2A	0.9900
C10—H10	0.9500	F1A—B1A	1.375 (5)
C9—C8	1.398 (2)	C4—C3	1.381 (2)
C9—H9	0.9500	C4—H4	0.9500
C8—C12	1.399 (2)	F2A—B1A	1.370 (5)
C8—C5	1.486 (2)	C3—H3	0.9500
C5—C4	1.396 (2)	B1A—F4A	1.384 (5)
C5—C6	1.400 (2)	B1A—F3A	1.404 (6)
N1—C3	1.348 (2)	B1B—F2B	1.364 (9)
N1—C7	1.349 (2)	B1B—F4B	1.372 (12)
N1—C2	1.479 (2)	B1B—F1B	1.380 (10)
C12—C11	1.376 (2)	B1B—F3B	1.406 (11)

C14—O4—H1B	109.7	O2—C1—O1	126.19 (15)
O3—C14—O4	126.40 (15)	O2—C1—C2	121.66 (14)
O3—C14—C13	116.20 (14)	O1—C1—C2	112.15 (13)
O4—C14—C13	117.40 (14)	N2—C11—C12	120.56 (15)
N2—C13—C14	113.73 (13)	N2—C11—H11	119.7
N2—C13—H13	108.8	C12—C11—H11	119.7
C14—C13—H13	108.8	C7—C6—C5	120.26 (15)
N2—C13—H13A	108.8	C7—C6—H6	119.9
C14—C13—H13A	108.8	C5—C6—H6	119.9
H13—C13—H13A	107.7	N1—C2—C1	109.32 (13)
C10—N2—C11	121.13 (14)	N1—C2—H2	109.8
C10—N2—C13	120.19 (13)	C1—C2—H2	109.8
C11—N2—C13	118.68 (13)	N1—C2—H2A	109.8
N2—C10—C9	120.27 (15)	C1—C2—H2A	109.8
N2—C10—H10	119.9	H2—C2—H2A	108.3
C9—C10—H10	119.9	C3—C4—C5	119.62 (16)
C10—C9—C8	119.83 (14)	C3—C4—H4	120.2
C10—C9—H9	120.1	C5—C4—H4	120.2
C8—C9—H9	120.1	N1—C3—C4	120.75 (16)
C9—C8—C12	118.34 (15)	N1—C3—H3	119.6
C9—C8—C5	121.34 (14)	C4—C3—H3	119.6
C12—C8—C5	120.25 (14)	F2A—B1A—F1A	108.7 (4)
C4—C5—C6	118.07 (15)	F2A—B1A—F4A	108.8 (4)
C4—C5—C8	121.48 (15)	F1A—B1A—F4A	109.9 (4)
C6—C5—C8	120.43 (15)	F2A—B1A—F3A	109.0 (3)
C3—N1—C7	121.07 (14)	F1A—B1A—F3A	109.7 (4)
C3—N1—C2	119.89 (14)	F4A—B1A—F3A	110.7 (4)
C7—N1—C2	118.82 (14)	F2B—B1B—F4B	112.4 (7)
C11—C12—C8	119.80 (15)	F2B—B1B—F1B	111.9 (7)
C11—C12—H12	120.1	F4B—B1B—F1B	112.4 (7)
C8—C12—H12	120.1	F2B—B1B—F3B	108.5 (8)
N1—C7—C6	120.23 (15)	F4B—B1B—F3B	105.1 (7)
N1—C7—H7	119.9	F1B—B1B—F3B	106.0 (8)
C6—C7—H7	119.9

O3—C14—C13—N2	168.93 (14)	C2—N1—C7—C6	−174.36 (15)
O4—C14—C13—N2	−11.5 (2)	C10—N2—C11—C12	−1.5 (2)
C14—C13—N2—C10	−107.12 (17)	C13—N2—C11—C12	178.25 (15)
C14—C13—N2—C11	73.10 (19)	C8—C12—C11—N2	−0.8 (3)
C11—N2—C10—C9	2.0 (2)	N1—C7—C6—C5	0.6 (3)
C13—N2—C10—C9	−177.78 (15)	C4—C5—C6—C7	−1.1 (2)
N2—C10—C9—C8	−0.2 (2)	C8—C5—C6—C7	177.33 (15)
C10—C9—C8—C12	−2.0 (2)	C3—N1—C2—C1	−84.48 (19)
C10—C9—C8—C5	175.02 (15)	C7—N1—C2—C1	90.16 (17)
C9—C8—C5—C4	30.3 (2)	O2—C1—C2—N1	10.3 (2)
C12—C8—C5—C4	−152.72 (17)	O1—C1—C2—N1	−169.22 (14)
C9—C8—C5—C6	−148.12 (17)	C6—C5—C4—C3	0.9 (3)
C12—C8—C5—C6	28.9 (2)	C8—C5—C4—C3	−177.53 (16)
C9—C8—C12—C11	2.5 (2)	C7—N1—C3—C4	−0.4 (3)
C5—C8—C12—C11	−174.60 (15)	C2—N1—C3—C4	174.09 (16)
C3—N1—C7—C6	0.2 (3)	C5—C4—C3—N1	−0.1 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C13—H13A···O1ⁱ	0.99	2.43	3.387 (2)	161
C10—H10···O3ⁱⁱ	0.95	2.61	3.126 (2)	114
C10—H10···O1ⁱ	0.95	2.51	3.362 (2)	149
C12—H12···O2ⁱⁱⁱ	0.95	2.28	3.188 (2)	159
C7—H7···O3^iv	0.95	2.34	3.208 (2)	151
C2—H2···O3^iv	0.99	2.36	3.231 (2)	146
C4—H4···O2^v	0.95	2.41	3.278 (2)	151
O4—H1B···O2^vi	1.42	2.39	3.3044 (17)	118.1
O1—H1B···O4^vii	1.05	1.42	2.4694 (18)	172.0

Symmetry codes: (i) −x+3/2, y−1/2, −z+3/2; (ii) −x, −y+1, −z+1; (iii) x−1, y, z; (iv) −x+1/2, y+1/2, −z+3/2; (v) x−1/2, −y+3/2, z−1/2; (vi) x−3/2, −y+3/2, z−1/2; (vii) x−9/2, −y−7/2, z−7/2.

Acknowledgements

We would like to thank Dr Mitsutaro Umehara for help with the database survey.

References

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CRYSTALLOGRAPHIC
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ISSN: 2056-9890

Volume 80| Part 7| July 2024| Pages 695-698

https://doi.org/10.1107/S2056989024005127

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research communications\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Crystal structures of 1,1′-bis­­(carb­­oxy­meth­yl)-4,4′-bipyridinium derivatives

1. Chemical context

2. Structural commentary

3. Supra­molecular features

4. Database survey

5. Synthesis and crystallization

6. Refinement

Supporting information

Acknowledgements

References

research communications

Crystal structures of 1,1′-bis(carboxymethyl)-4,4′-bipyridinium derivatives

3. Supramolecular features