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Acta Cryst. (2009). E65, o2333    [ doi:10.1107/S1600536809034448 ]

1,10-Phenanthrolin-1-ium 2-carboxy-4,5-dichlorobenzoate

G. Smith, U. D. Wermuth and J. M. White

Abstract top

In the structure of the 1:1 proton-transfer compound of 1,10-phenanthroline with 4,5-dichlorophthalic acid, C12H9N2+·C8H3Cl2O4-, determined at 130 K, the 1,10-phenanthrolinium cation and the hydrogen 4,5-dichlorophthalate anion associate through a single N-H...Ocarboxyl hydrogen bond giving discrete units which have no extension except through a number of weak cation C-H...Oanion associations and weak cation-anion aromatic ring [pi]-[pi] interactions [minimum centroid-centroid separation = 3.6815 (12) Å]. The anions are essentially planar "[maximum deviation 0.214 (1) Å (a carboxyl O)] with the syn-related H atom of the carboxyl group, forming a short intramolecular O-H...Ocarboxyl hydrogen bond.

Comment top

The 1:1 proton-transfer compounds of 4,5-dichlorophthalic acid (DCPA) with the aromatic nitrogen Lewis bases commonly have low-dimensional hydrogen-bonded structures (Smith et al., 2007, 2008a, 2008b, 2009a, 2009b; Bozkurt et al., 2006; Mallinson et al., 2003). In the two-dimensional examples the DCPA anions assume non-planar conformations and form into sheet substructures which in the case of the compounds with the meta- and para-aminobenzoic acids (Smith et al., 2008b) are extended into three-dimensional frameworks through peripheral cyclic head-to-head carboxylic acid hydrogen-bonding associations. However, with the majority of the structures, e.g. the brucinium salt (Smith et al., 2007), the DCPA anions are essentially planar with short intramolecular carboxylic acid O–H···Ocarboxyl hydrogen bonds. These features were therefore expected and found in the 1:1 proton-transfer compound of DCPA with 1,10-phenanthroline, (I), reported here.

In (I), a single N+–H···Ocarboxyl hydrogen bond links the phenanthroline cation and the DCPA anion (Fig. 1). A weak aromatic ring C–H···Ocarboxyl interaction (Table 1) completes an asymmetric R22(7) cyclic association (Etter et al., 1990). Three additional anion C–H···O interactions represent the only structure extensions present. Some overlap is present between the anion aromatic ring (C1–C6) and one six-membered ring of the cation (N10A, C9A, C8A, C7A, C6A, C14A) [minimum ring centroid separation, 3.6815 (12) Å] (Fig. 2), giving weak π–π stacking interactions (Fig. 3). The DCPA anion is essentially planar [torsion angles C2–C1–C11–O11, -168.30 (16)°: C1–C2–C21–O22, -179.53 (16)°], and exhibits a short intramolecular O–H···Ocarboxyl hydrogen bond [2.4054 (19) Å]. Associated with this bond is a significant distortion of the exo-C1 and C2 bond angles [C1–C2–C21, 128.55 (15) ° and C2–C1–C11, 129.18 (16) °]. This and a lengthening of the C1–C11 and C2–C21 bonds [1.538 (3) and 1.536 (3) Å] is common to the planar DCPA anions in the series of 1:1 proton-transfer compounds [angle range: 127.88 (16)° in the nicotinamide salt (Smith et al., 2009a) to 129.27 (14)° in the 8-aminoquinoline salt (Smith et al., 2008a); bond length range: 1.523 (3)–1.535 (3) Å, both in the brucinium salt (Smith et al., 2007).

Related literature top

For the structures of other hydrogen 4,5-dichlorophthalate salts, see: Mallinson et al. (2003); Bozkurt et al. (2006); Smith et al. (2007, 2008a,b, 2009a,b). For hydrogen-bond motifs, see: Etter et al. (1990).

Experimental top

The title compound (I) was synthesized by heating 1 mmol quantities of 1,10-phenanthroline and 4,5-dichlorophthalic acid in 50 ml of 95% ethanol for 10 min under reflux. After concentration to ca. 30 ml, partial room-temperature evaporation of the hot-filtered solution gave colourless plates (m.p. 464–465 K) suitable for data collection.

Refinement top

Hydrogen atoms potentially involved in hydrogen-bonding interactions were located by difference methods and their positional and isotropic displacement parameters were refined. Other H atoms were included in the refinement at calculated positions [C–H, 0.93 Å] and treated as riding models with Uiso(H) = 1.2Ueq (C).

Computing details top

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT (Bruker, 1999); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. Molecular configuration and atom numbering scheme for the 1,10-phenanthrolin-1-ium cation and the hydrogen 4,5-dichlorophthalate anion in (I). Non-H atoms are shown as 50% probability displacement ellipsoids. The inter-species hydrogen bond is shown as a dashed line.
[Figure 2] Fig. 2. Cation–anion aromatic ring overlap in (I) viewed down the approximate b direction in the unit cell. For symmetry code (iv): x + 1, y - 1, z.
[Figure 3] Fig. 3. Aromatic ring π–π interactions in a perspective view of part of the unit cell. Non-interactive H atoms are omitted. For symmetry code (v): x - 1, y, z.
1,10-Phenanthrolin-1-ium 2-carboxy-4,5-dichlorobenzoate top
Crystal data top
C12H9N2+·C8H3Cl2O4−F(000) = 424
Mr = 415.22Dx = 1.589 Mg m−3
Monoclinic, P21Melting point = 464–465 K
Hall symbol: P 2ybMo Kα radiation, λ = 0.71073 Å
a = 6.4598 (11) ÅCell parameters from 3630 reflections
b = 7.3696 (12) Åθ = 2.2–27.5°
c = 18.302 (3) ŵ = 0.41 mm−1
β = 94.978 (3)°T = 130 K
V = 868.0 (2) Å3Plate, colourless
Z = 20.55 × 0.45 × 0.05 mm
Data collection top
Bruker SMART CCD area-detector
diffractometer		3734 independent reflections
Radiation source: sealed tube3629 reflections with I > 2σ(I)
graphiteRint = 0.017
φ and ω scansθmax = 27.6°, θmin = 1.1°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		h = −5→8
Tmin = 0.81, Tmax = 0.98k = −9→9
5464 measured reflectionsl = −23→21
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.032H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.085 w = 1/[σ2(Fo2) + (0.053P)2 + 0.0522P]
where P = (Fo2 + 2Fc2)/3
S = 1.04(Δ/σ)max = 0.001
3734 reflectionsΔρmax = 0.30 e Å−3
261 parametersΔρmin = −0.19 e Å−3
1 restraintAbsolute structure: Flack (1983), 1564 Friedel pairs
Primary atom site location: structure-invariant direct methodsFlack parameter: 0.00 (4)
Crystal data top
C12H9N2+·C8H3Cl2O4−V = 868.0 (2) Å3
Mr = 415.22Z = 2
Monoclinic, P21Mo Kα radiation
a = 6.4598 (11) ŵ = 0.41 mm−1
b = 7.3696 (12) ÅT = 130 K
c = 18.302 (3) Å0.55 × 0.45 × 0.05 mm
β = 94.978 (3)°
Data collection top
Bruker SMART CCD area-detector
diffractometer		3734 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		3629 reflections with I > 2σ(I)
Tmin = 0.81, Tmax = 0.98Rint = 0.017
5464 measured reflectionsθmax = 27.6°
Refinement top
R[F2 > 2σ(F2)] = 0.032H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.085Δρmax = 0.30 e Å−3
S = 1.04Δρmin = −0.19 e Å−3
3734 reflectionsAbsolute structure: Flack (1983), 1564 Friedel pairs
261 parametersFlack parameter: 0.00 (4)
1 restraint
Special details top

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles

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
xyzUiso*/Ueq
N1A0.4667 (2)0.7304 (2)0.14863 (8)0.0192 (4)
N10A0.4177 (2)0.7715 (2)0.29542 (8)0.0212 (4)
C2A0.5046 (3)0.7149 (3)0.07881 (10)0.0232 (5)
C3A0.3645 (3)0.7828 (3)0.02322 (10)0.0277 (5)
C4A0.1845 (3)0.8641 (3)0.04213 (10)0.0268 (5)
C5A−0.0459 (3)0.9562 (3)0.13825 (11)0.0233 (5)
C6A−0.0804 (3)0.9634 (2)0.20961 (11)0.0246 (5)
C7A0.0442 (3)0.9113 (2)0.34093 (10)0.0259 (6)
C8A0.2013 (3)0.8540 (3)0.39058 (10)0.0286 (5)
C9A0.3857 (3)0.7854 (3)0.36523 (10)0.0253 (5)
C11A0.2617 (3)0.8274 (2)0.24641 (9)0.0184 (4)
C12A0.2916 (3)0.8115 (2)0.16952 (10)0.0178 (4)
C13A0.1421 (3)0.8783 (2)0.11565 (10)0.0207 (4)
C14A0.0717 (3)0.9002 (2)0.26564 (10)0.0207 (5)
Cl41.15820 (7)0.37080 (8)0.46649 (2)0.0332 (1)
Cl51.59276 (7)0.22144 (8)0.42219 (2)0.0316 (1)
O111.5052 (2)0.18688 (18)0.14604 (7)0.0251 (4)
O121.2404 (2)0.34157 (19)0.09355 (7)0.0265 (4)
O210.9277 (2)0.4836 (2)0.12771 (7)0.0271 (4)
O220.76248 (19)0.53666 (18)0.22655 (7)0.0254 (4)
C11.2820 (3)0.3211 (2)0.22748 (9)0.0179 (5)
C21.0928 (3)0.3971 (2)0.24707 (9)0.0178 (4)
C31.0603 (3)0.4092 (2)0.32117 (10)0.0206 (5)
C41.2096 (3)0.3536 (3)0.37559 (9)0.0215 (5)
C51.3983 (3)0.2862 (2)0.35636 (10)0.0207 (5)
C61.4314 (3)0.2693 (2)0.28333 (10)0.0196 (4)
C111.3502 (3)0.2788 (2)0.15083 (9)0.0195 (5)
C210.9127 (3)0.4764 (2)0.19673 (9)0.0193 (4)
H1A0.556 (3)0.683 (3)0.1842 (12)0.021 (5)*
H2A0.625800.658400.066800.0280*
H3A0.391900.77330−0.025700.0330*
H4A0.090100.910300.005600.0320*
H5A−0.144901.002100.103100.0280*
H6A−0.205401.010400.222900.0300*
H7A−0.078600.956700.356700.0310*
H8A0.186500.860300.440600.0340*
H9A0.490800.747800.399800.0300*
H30.935200.455800.334500.0250*
H61.557000.222000.270800.0230*
H121.113 (5)0.400 (4)0.1072 (17)0.035 (9)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N1A0.0167 (6)0.0212 (7)0.0195 (7)−0.0015 (6)0.0013 (5)0.0001 (6)
N10A0.0217 (7)0.0224 (7)0.0193 (7)0.0012 (6)0.0005 (6)−0.0004 (6)
C2A0.0222 (8)0.0261 (8)0.0222 (8)−0.0047 (8)0.0078 (7)−0.0028 (7)
C3A0.0292 (10)0.0360 (10)0.0182 (8)−0.0077 (8)0.0036 (7)0.0005 (7)
C4A0.0268 (9)0.0298 (9)0.0230 (8)−0.0069 (8)−0.0029 (7)0.0060 (8)
C5A0.0176 (8)0.0211 (8)0.0302 (9)−0.0004 (7)−0.0040 (7)0.0041 (7)
C6A0.0164 (8)0.0202 (9)0.0375 (10)0.0014 (7)0.0033 (7)−0.0017 (8)
C7A0.0242 (9)0.0253 (10)0.0295 (10)0.0011 (8)0.0104 (7)−0.0027 (7)
C8A0.0358 (10)0.0308 (10)0.0203 (8)0.0001 (9)0.0096 (7)−0.0023 (8)
C9A0.0295 (9)0.0263 (9)0.0197 (8)0.0025 (8)−0.0007 (7)0.0020 (7)
C11A0.0182 (8)0.0164 (7)0.0207 (8)−0.0009 (6)0.0026 (6)0.0009 (6)
C12A0.0163 (7)0.0166 (7)0.0204 (8)−0.0040 (6)0.0005 (6)0.0001 (6)
C13A0.0186 (7)0.0188 (7)0.0241 (8)−0.0039 (7)−0.0020 (6)0.0027 (7)
C14A0.0195 (8)0.0181 (8)0.0248 (8)−0.0031 (7)0.0039 (6)−0.0021 (7)
Cl40.0291 (2)0.0541 (3)0.0169 (2)0.0014 (2)0.0045 (2)−0.0034 (2)
Cl50.0251 (2)0.0463 (3)0.0221 (2)0.0067 (2)−0.0046 (2)−0.0001 (2)
O110.0227 (6)0.0297 (7)0.0236 (6)0.0044 (6)0.0058 (5)−0.0029 (5)
O120.0260 (6)0.0354 (7)0.0187 (6)0.0056 (6)0.0052 (5)0.0018 (5)
O210.0264 (7)0.0343 (7)0.0204 (6)0.0068 (6)0.0009 (5)0.0030 (5)
O220.0200 (6)0.0284 (7)0.0277 (7)0.0044 (5)0.0023 (5)0.0012 (5)
C10.0189 (8)0.0157 (8)0.0192 (8)−0.0027 (6)0.0029 (6)0.0006 (6)
C20.0188 (8)0.0149 (7)0.0197 (8)−0.0012 (6)0.0024 (6)0.0007 (6)
C30.0189 (8)0.0215 (9)0.0215 (8)−0.0012 (7)0.0032 (7)−0.0034 (6)
C40.0229 (8)0.0263 (9)0.0161 (7)−0.0035 (7)0.0057 (6)−0.0019 (7)
C50.0188 (8)0.0231 (8)0.0196 (8)−0.0005 (7)−0.0019 (6)0.0019 (7)
C60.0155 (7)0.0207 (8)0.0229 (8)0.0010 (6)0.0040 (6)−0.0014 (7)
C110.0202 (8)0.0197 (8)0.0192 (8)−0.0041 (7)0.0055 (6)−0.0012 (6)
C210.0168 (7)0.0173 (8)0.0233 (8)−0.0023 (6)−0.0005 (6)−0.0004 (6)
Geometric parameters (Å, °) top
Cl4—C41.7291 (17)C11A—C12A1.442 (2)
Cl5—C51.7305 (19)C11A—C14A1.412 (3)
O11—C111.218 (2)C12A—C13A1.408 (3)
O12—C111.299 (2)C2A—H2A0.9300
O21—C211.276 (2)C3A—H3A0.9300
O22—C211.236 (2)C4A—H4A0.9300
O12—H120.98 (3)C5A—H5A0.9300
N1A—C12A1.363 (2)C6A—H6A0.9300
N1A—C2A1.327 (2)C7A—H7A0.9300
N10A—C11A1.354 (2)C8A—H8A0.9300
N10A—C9A1.316 (2)C9A—H9A0.9300
N1A—H1A0.90 (2)C1—C21.419 (3)
C2A—C3A1.395 (3)C1—C111.538 (2)
C3A—C4A1.379 (3)C1—C61.397 (3)
C4A—C13A1.400 (3)C2—C211.536 (3)
C5A—C6A1.345 (3)C2—C31.393 (2)
C5A—C13A1.436 (3)C3—C41.387 (3)
C6A—C14A1.435 (3)C4—C51.390 (3)
C7A—C14A1.407 (3)C5—C61.377 (3)
C7A—C8A1.369 (3)C3—H30.9300
C8A—C9A1.409 (3)C6—H60.9300
C11—O12—H12111 (2)C14A—C6A—H6A119.00
C2A—N1A—C12A122.34 (16)C5A—C6A—H6A119.00
C9A—N10A—C11A116.68 (15)C8A—C7A—H7A121.00
C12A—N1A—H1A117.5 (13)C14A—C7A—H7A121.00
C2A—N1A—H1A120.1 (13)C9A—C8A—H8A120.00
N1A—C2A—C3A120.63 (18)C7A—C8A—H8A120.00
C2A—C3A—C4A118.74 (17)C8A—C9A—H9A118.00
C3A—C4A—C13A120.89 (17)N10A—C9A—H9A118.00
C6A—C5A—C13A120.73 (18)C2—C1—C11129.18 (16)
C5A—C6A—C14A121.35 (18)C2—C1—C6118.60 (15)
C8A—C7A—C14A118.87 (17)C6—C1—C11112.19 (16)
C7A—C8A—C9A119.43 (17)C1—C2—C21128.55 (15)
N10A—C9A—C8A123.79 (17)C1—C2—C3118.51 (16)
N10A—C11A—C14A124.31 (15)C3—C2—C21112.92 (16)
C12A—C11A—C14A117.85 (16)C2—C3—C4121.74 (17)
N10A—C11A—C12A117.83 (16)Cl4—C4—C5121.05 (14)
C11A—C12A—C13A120.89 (17)C3—C4—C5119.63 (16)
N1A—C12A—C11A119.61 (16)Cl4—C4—C3119.32 (15)
N1A—C12A—C13A119.50 (16)C4—C5—C6119.44 (17)
C5A—C13A—C12A118.94 (17)Cl5—C5—C4121.47 (14)
C4A—C13A—C5A123.19 (17)Cl5—C5—C6119.09 (15)
C4A—C13A—C12A117.87 (17)C1—C6—C5122.00 (17)
C6A—C14A—C7A122.97 (17)O11—C11—C1118.72 (15)
C7A—C14A—C11A116.91 (16)O12—C11—C1118.97 (15)
C6A—C14A—C11A120.09 (16)O11—C11—O12122.32 (16)
C3A—C2A—H2A120.00O22—C21—C2117.04 (15)
N1A—C2A—H2A120.00O21—C21—O22123.49 (17)
C2A—C3A—H3A121.00O21—C21—C2119.41 (16)
C4A—C3A—H3A121.00C2—C3—H3119.00
C3A—C4A—H4A120.00C4—C3—H3119.00
C13A—C4A—H4A120.00C1—C6—H6119.00
C6A—C5A—H5A120.00C5—C6—H6119.00
C13A—C5A—H5A120.00
C12A—N1A—C2A—C3A0.2 (3)N1A—C12A—C13A—C5A177.27 (16)
C2A—N1A—C12A—C11A−178.71 (17)C11A—C12A—C13A—C4A177.79 (16)
C2A—N1A—C12A—C13A1.4 (3)C11A—C12A—C13A—C5A−2.6 (2)
C11A—N10A—C9A—C8A0.0 (3)C6—C1—C2—C3−2.9 (2)
C9A—N10A—C11A—C12A−179.22 (16)C6—C1—C2—C21175.21 (15)
C9A—N10A—C11A—C14A0.8 (2)C11—C1—C2—C3174.90 (15)
N1A—C2A—C3A—C4A−0.9 (3)C11—C1—C2—C21−7.0 (3)
C2A—C3A—C4A—C13A−0.1 (3)C2—C1—C6—C51.5 (2)
C3A—C4A—C13A—C5A−177.89 (19)C11—C1—C6—C5−176.68 (14)
C3A—C4A—C13A—C12A1.7 (3)C2—C1—C11—O11−168.30 (16)
C13A—C5A—C6A—C14A2.4 (3)C2—C1—C11—O1211.4 (3)
C6A—C5A—C13A—C4A178.76 (18)C6—C1—C11—O119.6 (2)
C6A—C5A—C13A—C12A−0.8 (3)C6—C1—C11—O12−170.67 (15)
C5A—C6A—C14A—C7A177.74 (17)C1—C2—C3—C41.7 (2)
C5A—C6A—C14A—C11A−0.5 (2)C21—C2—C3—C4−176.64 (16)
C14A—C7A—C8A—C9A−0.1 (3)C1—C2—C21—O21−2.2 (3)
C8A—C7A—C14A—C6A−177.47 (17)C1—C2—C21—O22−179.53 (16)
C8A—C7A—C14A—C11A0.8 (2)C3—C2—C21—O21175.96 (15)
C7A—C8A—C9A—N10A−0.3 (3)C3—C2—C21—O22−1.4 (2)
N10A—C11A—C12A—N1A4.5 (2)C2—C3—C4—Cl4−179.50 (14)
N10A—C11A—C12A—C13A−175.62 (15)C2—C3—C4—C50.9 (3)
C14A—C11A—C12A—N1A−175.47 (15)Cl4—C4—C5—Cl5−1.6 (2)
C14A—C11A—C12A—C13A4.4 (2)Cl4—C4—C5—C6178.04 (14)
N10A—C11A—C14A—C6A177.13 (15)C3—C4—C5—Cl5178.02 (14)
N10A—C11A—C14A—C7A−1.2 (2)C3—C4—C5—C6−2.4 (3)
C12A—C11A—C14A—C6A−2.9 (2)Cl5—C5—C6—C1−179.20 (12)
C12A—C11A—C14A—C7A178.83 (14)C4—C5—C6—C11.2 (2)
N1A—C12A—C13A—C4A−2.4 (2)
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N1A—H1A···O220.90 (2)1.83 (2)2.6926 (19)158 (2)
N1A—H1A···N10A0.90 (2)2.38 (2)2.749 (2)104.3 (15)
O12—H12···O210.98 (3)1.43 (3)2.4054 (19)179 (4)
C2A—H2A···O210.932.523.279 (2)140
C3—H3···O220.932.262.647 (2)104
C3A—H3A···O11i0.932.443.355 (2)168
C4A—H4A···O21ii0.932.493.252 (2)139
C6—H6···O110.932.292.668 (2)103
C6A—H6A···O11iii0.932.593.270 (2)130
Symmetry codes: (i) −x+2, y+1/2, −z; (ii) −x+1, y+1/2, −z; (iii) x−2, y+1, z.
Table 1
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N1A—H1A···O220.90 (2)1.83 (2)2.6926 (19)158 (2)
N1A—H1A···N10A0.90 (2)2.38 (2)2.749 (2)104.3 (15)
O12—H12···O210.98 (3)1.43 (3)2.4054 (19)179 (4)
C2A—H2A···O210.932.523.279 (2)140
C3—H3···O220.932.262.647 (2)104
C3A—H3A···O11i0.932.443.355 (2)168
C4A—H4A···O21ii0.932.493.252 (2)139
C6—H6···O110.932.292.668 (2)103
C6A—H6A···O11iii0.932.593.270 (2)130
Symmetry codes: (i) −x+2, y+1/2, −z; (ii) −x+1, y+1/2, −z; (iii) x−2, y+1, z.
Acknowledgements top

The authors acknowledge financial support from the School of Physical and Chemical Sciences, Queensland University of Technology, and the School of Chemistry, University of Melbourne.

references
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