4,4′-Imino­dipyridinium bis­(hydrogen phthalate)

Martin, D.P.; LaDuca, R.L.

doi:10.1107/S1600536808031681

organic compounds

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ISSN: 2056-9890

Volume 64| Part 11| November 2008| Page o2153

doi:10.1107/S1600536808031681

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4,4′-Iminodipyridinium bis(hydrogen phthalate)

David P. Martin ^a and Robert L. LaDuca ^a ^*

^aLyman Briggs College, Department of Chemistry, Michigan State University, East Lansing, MI 48825, USA
^*Correspondence e-mail: laduca@msu.edu

(Received 26 September 2008; accepted 1 October 2008; online 22 October 2008)

In the title salt, C₁₀H₁₁N₃²⁺·2C₈H₅O₄⁻, doubly protonated 4,4′-dipyridylamine (dpa) cations participate in N—H⋯O hydrogen bonding with two hydrogen phthalate anions to form a neutral unit. Both anions contain an intramolecular O—H⋯O hydrogen bond. In the crystal structure, these units form two-dimensional layers through π–π stacking interactions with a centroid-to-centroid distance of 3.763 (3) Å. In turn, these layers aggregate in three dimensions by additional N—H⋯O hydrogen bonding. The assignment to the noncentrosymmetric space group P1 is corroborated by chemically unreasonable aromatic ring bond distances and poor K scale factor distributions for a disordered model in the centrosymmetric P $[\overline{1}]$ space group.

Related literature

For the crystal structure of dpa, see: Cordes et al. (2006 ). For a chiral dpa-containing coordination polymer, see: Montney et al. (2007 ). For carboxylic acid/imine co-crystals, see: Horiuchi et al. (2005 ); Bhogala & Nangia (2003 ). For charge-separated hydrogen bonding, see: Steiner (2002 ). For the preparation of dpa, see: Zapf et al. (1998 ).

Experimental

Crystal data

C₁₀H₁₁N₃²⁺·2C₈H₅O₄⁻
M_r = 503.46
Triclinic, P 1
a = 7.858 (2) Å
b = 8.101 (2) Å
c = 9.601 (3) Å
α = 85.673 (5)°
β = 85.186 (5)°
γ = 68.834 (4)°
V = 567.3 (3) Å³
Z = 1
Mo Kα radiation
μ = 0.11 mm⁻¹
T = 293 (2) K
0.75 × 0.60 × 0.30 mm

Data collection

Bruker SMART 1K diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.831, T_max = 0.967
6282 measured reflections
2513 independent reflections
2269 reflections with I > 2σ(I)
R_int = 0.014

Refinement

R[F² > 2σ(F²)] = 0.060
wR(F²) = 0.170
S = 1.06
2513 reflections
349 parameters
6 restraints
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.56 e Å⁻³
Δρ_min = −0.32 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O3—H3A⋯O2	1.07 (9)	1.37 (9)	2.386 (6)	155 (7)
O6—H7A⋯O7	1.03 (8)	1.37 (8)	2.396 (6)	172 (7)
N1—H1N⋯O1	0.86 (6)	1.90 (6)	2.757 (6)	177 (7)
N2—H2N⋯O6	0.85 (6)	2.00 (6)	2.834 (5)	167 (7)
N3—H3N⋯O8ⁱ	0.92 (5)	1.88 (5)	2.794 (5)	172 (5)
Symmetry code: (i) x, y-1, z+1.

Data collection: SMART (Bruker, 2001 ); cell refinement: SAINT-Plus (Bruker, 2003 ); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: CrystalMaker (Palmer, 2005 ); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536808031681/lh2702sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808031681/lh2702Isup2.hkl

checkCIF report

Comment top

Co-crystals containing carboxylic acids and imines have exhibited enticing physical properties such as ferroelectricity (Horiuchi et al., 2005). Proton transfer between carboxylic acid and pyridine components has been observed in this class of co-crystals (Bhogala & Nangia, 2003). Charge-separated hydrogen bonding interactions serve to promote the stability of these co-crystals (Steiner, 2002). Because of locked conformation between its pyridyl rings in the solid-state, crystals of pure dpa are noncentrosymmetric (Cordes et al., 2006). Coordination polymers containing dpa have been observed to crystallize in noncentrosymmetric space groups (Montney et al., 2007). Thus we have sought to prepare chiral dpa-containing co-crystals.

The asymmetric unit of the title salt contains a doubly protonated [H₂dpa]²⁺ dication, and two hydrogen phthalate ([phtH]^-) ions (Fig. 1). The similar C—O bond lengths at the carboxylate termini marked by C17 and C28 indicate the presence of delocalized π bonds. On the other hand the C—O bond distances at C18 and C27 show greater C═O and C—O single bond character.

Each [H₂dpa]²⁺ dication is linked to [Hpht]^- anions on either side to form neutral [H₂dpa][[Hpht]₂ units, via N—H···O hydrogen bonding donation from both of its pyridinium termini to [Hpht]^- carboxylate oxygen atoms. These neutral units then engage in π–π stacking between pyridyl and benzene rings (centroid-to-centroid distance = 3.763 Å) to construct pseudo two-dimensional layer patterns that lie parallel to the (101) crystal planes (Fig. 2).

The [H₂dpa][[Hpht]₂ layers are connected into the pseudo three-dimensional structure of the title compound via N—H···O hydrogen bonding mechanisms instilled by the central amine units of the [H₂dpa]²⁺ dications (Fig. 3). Geometric parameters for the hydrogen bonding interactions are given in Table 1.

The assignment to the noncentrosymmetric space group P1 is corroborated by chemically unreasonable aromatic ring bond distances (1.0 and 1.7 Å) and poor K scale factors distributions for a disordered model in the centrosymmetric P1 space group.

Related literature top

For the crystal structure of dpa, see: Cordes et al. (2006). For a chiral dpa-containing coordination polymer, see: Montney et al. (2007). For carboxylic acid/imine co-crystals, see: Horiuchi et al. (2005); Bhogala & Nangia (2003). For charge-separated hydrogen bonding, see: Steiner (2002). For the preparation of dpa, see: Zapf et al. (1998).

Experimental top

Phthalic acid was obtained commercially. 4,4'-dipyridylamine was prepared via a published procedure (Zapf et al., 1998). A mixture of phthalic acid (96 mg, 0.58 mmol) and 4,4'-dipyridylamine (50 mg, 0.29 mmol) was placed in 10.0 g water (550 mmol) in a 25 ml beaker. The solution was then heated to boiling. Large colourless blocks of the title compound were isolated after the solution was cooled to 298K and allowed to stand undisturbed for 3 d.

Computing details top

Data collection: SMART (Bruker, 2001); cell refinement: SAINT-Plus (Bruker, 2003); data reduction: SAINT-Plus (Bruker, 2003); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: CrystalMaker (Palmer, 2005); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

	Fig. 1. Asymmetric unit of the title compound, showing 50% probability ellipsoids and atom numbering scheme. Hydrogen atoms are represented as short gray sticks. Color codes: light-blue N, red O, black C. Hydrogen bonding is shown as dashed lines.
	Fig. 2. A pseudo layer in the title compound. Color codes: light-blue N, red O, black C, pink H. Hydrogen bonding is shown as dashed lines.
	Fig. 3. Packing diagram illustrating the stacking of layers to form the 3-D crystal structure of the title compound. Hydrogen bonding is shown as dashed lines.

4,4'-Iminodipyridinium bis(hydrogen phthalate) top

Crystal data top

C₁₀H₁₁N₃²⁺·2C₈H₅O₄⁻	Z = 1
M_r = 503.46	F(000) = 262
Triclinic, P1	D_x = 1.474 Mg m⁻³
Hall symbol: P 1	Mo Kα radiation, λ = 0.71073 Å
a = 7.858 (2) Å	Cell parameters from 6282 reflections
b = 8.101 (2) Å	θ = 2.1–28.0°
c = 9.601 (3) Å	µ = 0.11 mm⁻¹
α = 85.673 (5)°	T = 293 K
β = 85.186 (5)°	Block, colourless
γ = 68.834 (4)°	0.75 × 0.60 × 0.30 mm
V = 567.3 (3) Å³

Data collection top

Bruker SMART 1K diffractometer	2513 independent reflections
Radiation source: fine-focus sealed tube	2269 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.014
ω scans	θ_max = 28.0°, θ_min = 2.1°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −10→10
T_min = 0.831, T_max = 0.967	k = −10→10
6282 measured reflections	l = −12→12

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)] = 0.060	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.170	H atoms treated by a mixture of independent and constrained refinement
S = 1.06	w = 1/[σ²(F_o²) + (0.0871P)² + 0.2863P] where P = (F_o² + 2F_c²)/3
2513 reflections	(Δ/σ)_max < 0.001
349 parameters	Δρ_max = 0.56 e Å⁻³
6 restraints	Δρ_min = −0.32 e Å⁻³

Crystal data top

C₁₀H₁₁N₃²⁺·2C₈H₅O₄⁻	γ = 68.834 (4)°
M_r = 503.46	V = 567.3 (3) Å³
Triclinic, P1	Z = 1
a = 7.858 (2) Å	Mo Kα radiation
b = 8.101 (2) Å	µ = 0.11 mm⁻¹
c = 9.601 (3) Å	T = 293 K
α = 85.673 (5)°	0.75 × 0.60 × 0.30 mm
β = 85.186 (5)°

Data collection top

Bruker SMART 1K diffractometer	2513 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	2269 reflections with I > 2σ(I)
T_min = 0.831, T_max = 0.967	R_int = 0.014
6282 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.060	6 restraints
wR(F²) = 0.170	H atoms treated by a mixture of independent and constrained refinement
S = 1.06	Δρ_max = 0.56 e Å⁻³
2513 reflections	Δρ_min = −0.32 e Å⁻³
349 parameters

Special details top

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > 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) top

	x	y	z	U_iso*/U_eq
O1	−0.9711 (7)	0.8965 (7)	1.1049 (4)	0.0832 (14)
O2	−0.7469 (5)	0.7612 (6)	1.2383 (5)	0.0712 (12)
O3	−0.6750 (5)	0.5656 (7)	1.4411 (6)	0.0824 (14)
H3A	−0.691 (11)	0.624 (10)	1.337 (9)	0.099*
O4	−0.8021 (6)	0.3983 (6)	1.5649 (5)	0.0780 (13)
O5	0.3019 (7)	1.2225 (8)	0.2453 (5)	0.0926 (17)
O6	0.0684 (5)	1.3566 (6)	0.1220 (5)	0.0709 (12)
H7A	0.043 (9)	1.430 (9)	0.028 (8)	0.085*
O7	−0.0087 (5)	1.5473 (6)	−0.0843 (5)	0.0802 (13)
O8	0.1036 (5)	1.7269 (5)	−0.2062 (4)	0.0654 (10)
N1	−0.6896 (8)	0.9599 (7)	0.9469 (5)	0.0655 (14)
H1N	−0.780 (6)	0.944 (9)	0.995 (6)	0.079*
N2	−0.0792 (9)	1.2304 (7)	0.3688 (5)	0.0760 (18)
H2N	−0.047 (10)	1.285 (8)	0.299 (5)	0.091*
N3	−0.2299 (5)	0.9798 (5)	0.7185 (4)	0.0495 (8)
H3N	−0.121 (5)	0.902 (6)	0.751 (6)	0.059*
C1	−0.7118 (7)	1.0624 (9)	0.8305 (7)	0.0714 (17)
H1	−0.8289	1.1282	0.8031	0.086*
C2	−0.5601 (8)	1.0716 (7)	0.7497 (5)	0.0605 (14)
H2	−0.5747	1.1424	0.6674	0.073*
C3	−0.3924 (6)	0.9770 (7)	0.7916 (5)	0.0533 (12)
C4	−0.3767 (8)	0.8754 (8)	0.9177 (6)	0.0689 (16)
H4	−0.2625	0.8122	0.9517	0.083*
C5	−0.5320 (10)	0.8709 (8)	0.9894 (6)	0.0713 (16)
H5	−0.5226	0.8009	1.0718	0.086*
C6	0.0413 (8)	1.1117 (8)	0.4402 (7)	0.0668 (15)
H6	0.1643	1.0811	0.4115	0.080*
C7	−0.0060 (7)	1.0321 (7)	0.5539 (6)	0.0607 (13)
H7	0.0843	0.9471	0.6042	0.073*
C8	−0.1878 (8)	1.0729 (6)	0.5996 (5)	0.0517 (11)
C9	−0.3186 (7)	1.1998 (8)	0.5237 (6)	0.0618 (14)
H9	−0.4424	1.2313	0.5500	0.074*
C10	−0.2574 (9)	1.2797 (8)	0.4051 (6)	0.0697 (15)
H10	−0.3414	1.3673	0.3517	0.084*
C11	−1.0440 (6)	0.7547 (6)	1.3134 (4)	0.0392 (9)
C12	−1.2276 (6)	0.8392 (7)	1.2857 (5)	0.0508 (11)
H12	−1.2573	0.9150	1.2065	0.061*
C13	−1.3670 (7)	0.8140 (8)	1.3720 (7)	0.0642 (14)
H13	−1.4881	0.8714	1.3502	0.077*
C14	−1.3265 (7)	0.7059 (8)	1.4877 (6)	0.0639 (15)
H14	−1.4203	0.6922	1.5477	0.077*
C15	−1.1462 (7)	0.6149 (7)	1.5178 (5)	0.0547 (12)
H15	−1.1207	0.5380	1.5967	0.066*
C16	−1.0025 (6)	0.6360 (5)	1.4328 (4)	0.0384 (9)
C17	−0.9122 (7)	0.8067 (6)	1.2125 (5)	0.0493 (11)
C18	−0.8166 (7)	0.5225 (7)	1.4825 (6)	0.0586 (12)
C21	0.3638 (5)	1.3702 (5)	0.0345 (4)	0.0391 (9)
C22	0.5473 (7)	1.2878 (7)	0.0605 (5)	0.0535 (12)
H22	0.5797	1.2125	0.1396	0.064*
C23	0.6836 (7)	1.3158 (8)	−0.0294 (7)	0.0640 (14)
H23	0.8060	1.2567	−0.0120	0.077*
C24	0.6362 (7)	1.4317 (9)	−0.1449 (6)	0.0632 (14)
H24	0.7259	1.4535	−0.2048	0.076*
C25	0.4570 (7)	1.5131 (7)	−0.1694 (5)	0.0539 (12)
H25	0.4265	1.5892	−0.2483	0.065*
C26	0.3158 (6)	1.4886 (6)	−0.0825 (4)	0.0420 (9)
C27	0.2367 (8)	1.3142 (7)	0.1443 (5)	0.0548 (12)
C28	0.1238 (6)	1.5967 (6)	−0.1279 (5)	0.0488 (10)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.080 (3)	0.110 (4)	0.055 (2)	−0.037 (3)	0.000 (2)	0.034 (2)
O2	0.044 (2)	0.090 (3)	0.076 (3)	−0.0278 (18)	0.0088 (17)	0.023 (2)
O3	0.0427 (19)	0.099 (3)	0.106 (3)	−0.030 (2)	−0.022 (2)	0.032 (3)
O4	0.081 (3)	0.072 (3)	0.072 (3)	−0.020 (2)	−0.018 (2)	0.032 (2)
O5	0.083 (3)	0.134 (5)	0.058 (2)	−0.047 (3)	0.000 (2)	0.048 (3)
O6	0.046 (2)	0.083 (3)	0.079 (3)	−0.0271 (18)	0.0162 (18)	0.022 (2)
O7	0.0424 (18)	0.088 (3)	0.108 (3)	−0.0269 (18)	−0.0145 (19)	0.040 (2)
O8	0.054 (2)	0.064 (2)	0.071 (2)	−0.0164 (17)	−0.0107 (17)	0.0269 (18)
N1	0.071 (3)	0.081 (3)	0.061 (3)	−0.051 (3)	0.032 (2)	−0.020 (2)
N2	0.125 (5)	0.062 (3)	0.051 (2)	−0.054 (3)	0.037 (3)	0.000 (2)
N3	0.0458 (17)	0.056 (2)	0.0426 (18)	−0.0175 (15)	0.0023 (14)	0.0135 (15)
C1	0.040 (3)	0.084 (4)	0.082 (4)	−0.008 (3)	−0.013 (2)	−0.014 (3)
C2	0.084 (4)	0.056 (3)	0.039 (2)	−0.024 (3)	−0.011 (2)	0.018 (2)
C3	0.045 (2)	0.070 (3)	0.050 (3)	−0.028 (2)	0.0135 (19)	−0.015 (2)
C4	0.063 (3)	0.066 (3)	0.051 (3)	0.006 (2)	−0.005 (2)	0.010 (2)
C5	0.098 (5)	0.059 (3)	0.049 (3)	−0.025 (3)	0.005 (3)	0.018 (2)
C6	0.054 (3)	0.066 (3)	0.083 (4)	−0.028 (2)	0.018 (3)	−0.015 (3)
C7	0.049 (3)	0.067 (3)	0.057 (3)	−0.009 (2)	−0.007 (2)	−0.003 (2)
C8	0.076 (3)	0.043 (2)	0.038 (2)	−0.027 (2)	0.011 (2)	0.0008 (17)
C9	0.044 (2)	0.078 (4)	0.063 (3)	−0.021 (2)	0.007 (2)	−0.014 (3)
C10	0.082 (4)	0.058 (3)	0.058 (3)	−0.012 (3)	−0.018 (3)	0.014 (2)
C11	0.037 (2)	0.048 (2)	0.0359 (19)	−0.0200 (17)	−0.0010 (16)	0.0031 (16)
C12	0.040 (2)	0.059 (3)	0.051 (3)	−0.016 (2)	−0.0064 (19)	0.009 (2)
C13	0.036 (2)	0.077 (4)	0.077 (4)	−0.018 (2)	−0.004 (2)	0.002 (3)
C14	0.047 (3)	0.078 (4)	0.076 (4)	−0.037 (3)	0.015 (2)	−0.001 (3)
C15	0.060 (3)	0.065 (3)	0.048 (3)	−0.036 (2)	0.006 (2)	0.009 (2)
C16	0.041 (2)	0.041 (2)	0.038 (2)	−0.0194 (17)	−0.0055 (16)	0.0053 (16)
C17	0.054 (3)	0.055 (3)	0.041 (2)	−0.025 (2)	0.0030 (19)	0.0045 (19)
C18	0.054 (3)	0.057 (3)	0.064 (3)	−0.019 (2)	−0.012 (2)	0.009 (2)
C21	0.038 (2)	0.040 (2)	0.039 (2)	−0.0150 (16)	−0.0002 (16)	0.0020 (16)
C22	0.051 (3)	0.058 (3)	0.052 (3)	−0.020 (2)	−0.016 (2)	0.014 (2)
C23	0.034 (2)	0.077 (3)	0.083 (4)	−0.024 (2)	−0.004 (2)	0.002 (3)
C24	0.047 (3)	0.088 (4)	0.061 (3)	−0.037 (3)	0.015 (2)	0.004 (3)
C25	0.050 (3)	0.065 (3)	0.049 (3)	−0.027 (2)	−0.001 (2)	0.014 (2)
C26	0.0350 (19)	0.052 (2)	0.041 (2)	−0.0199 (17)	0.0055 (16)	−0.0010 (18)
C27	0.062 (3)	0.058 (3)	0.045 (2)	−0.026 (2)	0.015 (2)	0.004 (2)
C28	0.042 (2)	0.051 (2)	0.051 (2)	−0.0165 (18)	−0.0068 (18)	0.013 (2)

Geometric parameters (Å, º) top

O1—C17	1.238 (6)	C7—C8	1.385 (7)
O2—C17	1.257 (6)	C7—H7	0.9300
O2—H3A	1.37 (9)	C8—C9	1.376 (8)
O3—C18	1.305 (7)	C9—C10	1.403 (8)
O3—H3A	1.07 (9)	C9—H9	0.9300
O4—C18	1.210 (6)	C10—H10	0.9300
O5—C27	1.206 (7)	C11—C12	1.395 (6)
O6—C27	1.273 (7)	C11—C16	1.420 (6)
O6—H7A	1.03 (8)	C11—C17	1.507 (6)
O7—C28	1.273 (6)	C12—C13	1.383 (7)
O7—H7A	1.37 (8)	C12—H12	0.9300
O8—C28	1.218 (6)	C13—C14	1.347 (8)
N1—C5	1.271 (9)	C13—H13	0.9300
N1—C1	1.325 (9)	C14—C15	1.385 (8)
N1—H1N	0.86 (6)	C14—H14	0.9300
N2—C6	1.282 (9)	C15—C16	1.391 (6)
N2—C10	1.333 (9)	C15—H15	0.9300
N2—H2N	0.85 (6)	C16—C18	1.513 (7)
N3—C8	1.403 (5)	C21—C22	1.388 (6)
N3—C3	1.411 (5)	C21—C26	1.404 (6)
N3—H3N	0.92 (5)	C21—C27	1.547 (6)
C1—C2	1.389 (9)	C22—C23	1.391 (7)
C1—H1	0.9300	C22—H22	0.9300
C2—C3	1.342 (8)	C23—C24	1.382 (9)
C2—H2	0.9300	C23—H23	0.9300
C3—C4	1.400 (7)	C24—C25	1.355 (8)
C4—C5	1.361 (9)	C24—H24	0.9300
C4—H4	0.9300	C25—C26	1.394 (6)
C5—H5	0.9300	C25—H25	0.9300
C6—C7	1.321 (9)	C26—C28	1.527 (6)
C6—H6	0.9300

C17—O2—H3A	114 (4)	C13—C12—C11	122.2 (4)
C18—O3—H3A	110 (4)	C13—C12—H12	118.9
C27—O6—H7A	109 (4)	C11—C12—H12	118.9
C28—O7—H7A	109 (3)	C14—C13—C12	119.7 (5)
C5—N1—C1	121.9 (5)	C14—C13—H13	120.2
C5—N1—H1N	116 (5)	C12—C13—H13	120.2
C1—N1—H1N	122 (5)	C13—C14—C15	120.4 (5)
C6—N2—C10	122.0 (5)	C13—C14—H14	119.8
C6—N2—H2N	120 (5)	C15—C14—H14	119.8
C10—N2—H2N	118 (5)	C14—C15—C16	121.4 (5)
C8—N3—C3	135.3 (4)	C14—C15—H15	119.3
C8—N3—H3N	108 (4)	C16—C15—H15	119.3
C3—N3—H3N	117 (4)	C15—C16—C11	118.6 (4)
N1—C1—C2	119.9 (5)	C15—C16—C18	113.1 (4)
N1—C1—H1	120.0	C11—C16—C18	128.3 (4)
C2—C1—H1	120.0	O1—C17—O2	121.0 (5)
C3—C2—C1	119.2 (5)	O1—C17—C11	118.5 (5)
C3—C2—H2	120.4	O2—C17—C11	120.5 (4)
C1—C2—H2	120.4	O4—C18—O3	120.8 (5)
C2—C3—C4	118.6 (5)	O4—C18—C16	119.8 (5)
C2—C3—N3	123.6 (5)	O3—C18—C16	119.3 (5)
C4—C3—N3	117.8 (5)	C22—C21—C26	118.9 (4)
C5—C4—C3	118.6 (5)	C22—C21—C27	112.6 (4)
C5—C4—H4	120.7	C26—C21—C27	128.5 (4)
C3—C4—H4	120.7	C21—C22—C23	121.3 (4)
N1—C5—C4	121.8 (5)	C21—C22—H22	119.4
N1—C5—H5	119.1	C23—C22—H22	119.4
C4—C5—H5	119.1	C24—C23—C22	119.6 (5)
N2—C6—C7	121.3 (5)	C24—C23—H23	120.2
N2—C6—H6	119.4	C22—C23—H23	120.2
C7—C6—H6	119.4	C25—C24—C23	118.9 (4)
C6—C7—C8	121.1 (5)	C25—C24—H24	120.5
C6—C7—H7	119.4	C23—C24—H24	120.5
C8—C7—H7	119.4	C24—C25—C26	123.4 (4)
C9—C8—C7	118.2 (4)	C24—C25—H25	118.3
C9—C8—N3	123.2 (5)	C26—C25—H25	118.3
C7—C8—N3	118.5 (5)	C25—C26—C21	117.8 (4)
C8—C9—C10	117.3 (5)	C25—C26—C28	114.7 (4)
C8—C9—H9	121.4	C21—C26—C28	127.5 (3)
C10—C9—H9	121.4	O5—C27—O6	121.4 (5)
N2—C10—C9	120.1 (5)	O5—C27—C21	119.0 (5)
N2—C10—H10	119.9	O6—C27—C21	119.4 (4)
C9—C10—H10	119.9	O8—C28—O7	122.3 (5)
C12—C11—C16	117.7 (4)	O8—C28—C26	118.4 (4)
C12—C11—C17	114.6 (4)	O7—C28—C26	119.3 (4)
C16—C11—C17	127.7 (4)

C5—N1—C1—C2	1.5 (9)	C12—C11—C16—C18	177.2 (5)
N1—C1—C2—C3	−0.6 (9)	C17—C11—C16—C18	−4.8 (8)
C1—C2—C3—C4	−1.4 (8)	C12—C11—C17—O1	−10.2 (7)
C1—C2—C3—N3	−178.7 (5)	C16—C11—C17—O1	171.7 (5)
C8—N3—C3—C2	3.8 (8)	C12—C11—C17—O2	169.0 (5)
C8—N3—C3—C4	−173.6 (5)	C16—C11—C17—O2	−9.0 (8)
C2—C3—C4—C5	2.7 (9)	C15—C16—C18—O4	17.3 (7)
N3—C3—C4—C5	−179.9 (5)	C11—C16—C18—O4	−162.1 (5)
C1—N1—C5—C4	−0.2 (10)	C15—C16—C18—O3	−159.4 (5)
C3—C4—C5—N1	−1.9 (10)	C11—C16—C18—O3	21.3 (8)
C10—N2—C6—C7	0.1 (10)	C26—C21—C22—C23	−2.2 (8)
N2—C6—C7—C8	0.5 (9)	C27—C21—C22—C23	177.6 (5)
C6—C7—C8—C9	−0.4 (8)	C21—C22—C23—C24	1.9 (9)
C6—C7—C8—N3	178.0 (5)	C22—C23—C24—C25	−1.3 (10)
C3—N3—C8—C9	1.6 (8)	C23—C24—C25—C26	1.2 (10)
C3—N3—C8—C7	−176.7 (5)	C24—C25—C26—C21	−1.4 (8)
C7—C8—C9—C10	−0.3 (8)	C24—C25—C26—C28	178.6 (5)
N3—C8—C9—C10	−178.6 (5)	C22—C21—C26—C25	1.9 (7)
C6—N2—C10—C9	−0.8 (9)	C27—C21—C26—C25	−177.9 (5)
C8—C9—C10—N2	0.9 (9)	C22—C21—C26—C28	−178.1 (5)
C16—C11—C12—C13	1.7 (7)	C27—C21—C26—C28	2.1 (8)
C17—C11—C12—C13	−176.5 (5)	C22—C21—C27—O5	6.8 (7)
C11—C12—C13—C14	0.6 (9)	C26—C21—C27—O5	−173.4 (6)
C12—C13—C14—C15	−2.4 (9)	C22—C21—C27—O6	−168.9 (5)
C13—C14—C15—C16	1.9 (9)	C26—C21—C27—O6	10.9 (8)
C14—C15—C16—C11	0.4 (7)	C25—C26—C28—O8	−20.4 (7)
C14—C15—C16—C18	−179.0 (5)	C21—C26—C28—O8	159.6 (5)
C12—C11—C16—C15	−2.2 (6)	C25—C26—C28—O7	158.8 (5)
C17—C11—C16—C15	175.9 (5)	C21—C26—C28—O7	−21.2 (8)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3A···O2	1.07 (9)	1.37 (9)	2.386 (6)	155 (7)
O6—H7A···O7	1.03 (8)	1.37 (8)	2.396 (6)	172 (7)
N1—H1N···O1	0.86 (6)	1.90 (6)	2.757 (6)	177 (7)
N2—H2N···O6	0.85 (6)	2.00 (6)	2.834 (5)	167 (7)
N3—H3N···O8ⁱ	0.92 (5)	1.88 (5)	2.794 (5)	172 (5)

Symmetry code: (i) x, y−1, z+1.

Experimental details

Crystal data
Chemical formula	C₁₀H₁₁N₃²⁺·2C₈H₅O₄⁻
M_r	503.46
Crystal system, space group	Triclinic, P1
Temperature (K)	293
a, b, c (Å)	7.858 (2), 8.101 (2), 9.601 (3)
α, β, γ (°)	85.673 (5), 85.186 (5), 68.834 (4)
V (Å³)	567.3 (3)
Z	1
Radiation type	Mo Kα
µ (mm⁻¹)	0.11
Crystal size (mm)	0.75 × 0.60 × 0.30

Data collection
Diffractometer	Bruker SMART 1K diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.831, 0.967
No. of measured, independent and observed [I > 2σ(I)] reflections	6282, 2513, 2269
R_int	0.014
(sin θ/λ)_max (Å⁻¹)	0.661

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.060, 0.170, 1.06
No. of reflections	2513
No. of parameters	349
No. of restraints	6
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.56, −0.32

Computer programs: SMART (Bruker, 2001), SAINT-Plus (Bruker, 2003), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), CrystalMaker (Palmer, 2005).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3A···O2	1.07 (9)	1.37 (9)	2.386 (6)	155 (7)
O6—H7A···O7	1.03 (8)	1.37 (8)	2.396 (6)	172 (7)
N1—H1N···O1	0.86 (6)	1.90 (6)	2.757 (6)	177 (7)
N2—H2N···O6	0.85 (6)	2.00 (6)	2.834 (5)	167 (7)
N3—H3N···O8ⁱ	0.92 (5)	1.88 (5)	2.794 (5)	172 (5)

Symmetry code: (i) x, y−1, z+1.

Acknowledgements

We gratefully acknowledge Michigan State University for funding this work. We thank Dr Richard J. Staples for helpful discussions.

References

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