Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536807022866/gg3091sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S1600536807022866/gg3091Isup2.hkl |
CCDC reference: 651461
Key indicators
- Single-crystal X-ray study
- T = 150 K
- Mean (C-C) = 0.003 Å
- R factor = 0.054
- wR factor = 0.156
- Data-to-parameter ratio = 18.3
checkCIF/PLATON results
No syntax errors found
Alert level B ABSTM02_ALERT_3_B The ratio of expected to reported Tmax/Tmin(RR') is < 0.75 Tmin and Tmax reported: 0.665 1.070 Tmin(prime) and Tmax expected: 0.851 0.912 RR(prime) = 0.666 Please check that your absorption correction is appropriate. PLAT061_ALERT_3_B Tmax/Tmin Range Test RR' too Large ............. 0.66
Alert level C PLAT029_ALERT_3_C _diffrn_measured_fraction_theta_full Low ....... 0.96 PLAT062_ALERT_4_C Rescale T(min) & T(max) by ..................... 0.85 PLAT480_ALERT_4_C Long H...A H-Bond Reported H16B .. CL19 .. 2.91 Ang.
Alert level G ABSTM02_ALERT_3_G When printed, the submitted absorption T values will be replaced by the scaled T values. Since the ratio of scaled T's is identical to the ratio of reported T values, the scaling does not imply a change to the absorption corrections used in the study. Ratio of Tmax expected/reported 0.852 Tmax scaled 0.912 Tmin scaled 0.567
0 ALERT level A = In general: serious problem 2 ALERT level B = Potentially serious problem 3 ALERT level C = Check and explain 1 ALERT level G = General alerts; check 0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data 0 ALERT type 2 Indicator that the structure model may be wrong or deficient 4 ALERT type 3 Indicator that the structure quality may be low 2 ALERT type 4 Improvement, methodology, query or suggestion 0 ALERT type 5 Informative message, check
Compound (I) was prepared by the previously reported method (Pask, Camm, Kilner & Halcrow, 2006). Recrystallization of the crude solid by slow evaporation of a 2M HCl solution yielded colourless rectangular prisms.
The pyridinium N1 and C6 sites were distinguished from their isotropic thermal parameters, and on the basis that N1 in the model donates a short hydrogen bond to Cl19 while C6 does not take part in hydrogen bonding. All non-H atoms were refined anisotropically. All H atoms were located in the difference map, but several of them (notably the methyl groups) did not refine satisfactorily when their positions were allowed to refine freely. Hence, in the final model all H atoms were placed in calculated positions and refined using a riding model with methyl group torsions allowed to refine freely. The fixed bond distances and isotropic thermal parameters for the H atom refinements were: C—H(aryl) = 0.95Å and Uiso = 1.2Ueq(C); C—H(methyl) = 0.98Å and 1.5Ueq(C); and, N—H = 0.88Å and Uiso = 1.2Ueq(N).
The pyrazole ring is an attractive functionality for transition metal supramolecular chemistry in that it possesses a Lewis basic pyridinic N-donor and a Lewis acidic pyrrolic N—H group in adjacent sites. It can therefore be a ditopic ligand for metal salts, binding a metal cation and anion simultaneously, placing the two guests 3.5–4.5Å apart (Reger et al., 1994; Renard et al., 2002; Nieto et al., 2006). As a continuation of our own studies of metal-organic supramolecular chemistry of 5-substituted N—H pyrazoles (Liu et al., 2004; Renard et al., 2002 & 2006 and refs. therein), we have investigated the synthesis of bidentate ligands derived from 3-(pyrid-2-yl)-1H-pyrazole and their metal complexes (Pask, Camm, Kilner & Halcrow, 2006; Pask, Camm, Bullen et al., 2006; Jones et al., 2006 & 2007). During this work, we were interested in investigating how these ligands interact with anions in the absence of a metal cation and have examined the crystal structure of the hydrochloride salt of the title compound (I).
The asymmetric unit of (I) contains one formula unit, with the cation and anion both lying on general positions. All bond lengths and angles in the organic cation lie within the expected ranges. The pyridinium and pyrazole rings in (I) are not coplanar, having a dihedral angle of 17.45 (10)° between their least squares planes. The dihedral angle between the pyrazole and amido groups is smaller, at 10.48 (11)°. The conformation of (I), and of the related neutral compound N-(5-{pyridin-2-yl}pyrazol-3-yl)methylamide (II) (Pask, Camm, Kilner & Halcrow, 2006), differ in two important ways: a) the N atoms of the pyridine and pyrazole rings have an anti disposition in (I), but are syn to each other in (II) and b) the amide N—H group is anti to the pyrazole N atoms in (I). Since the amide bond has its usual transoid conformation, that facilitates the formation of an intramolecular hydrogen bond from the pyrazole ring to the amide carbonyl group, N8—H8···O18. However, in (II) these two groups are syn to each other, placing the carbonyl group on the opposite side of the pyrazole ring so that no intramolecular hydrogen bond is formed.
There are five intermolecular contacts to the Cl- ion Cl19 that are shorter than the sum of van der Waals radii of a Cl (1.8 Å) and H (1.2 Å) atom [Pauling (1960). The Nature of the Chemical Bond, 3rd ed. Ithaca: Cornell University Press.] (Fig. 2). These are: two N—H···Cl hydrogen bonds, from N12—H12 and N1i—H1i; and, three weaker C—H···Cl contacts from C11i—H11i, C4ii—H4ii and C16—H16B, with H···Cl = 2.76–2.91 Å [symmetry codes: (i) 1 - x, 2 - y, -z; (ii) 2 - x, 2 - y, -z]. The geometry about Cl19 is therefore is very distorted, with τ = 0.44 placing it midway between the square pyramidal (τ = 0) and trigonal bipyramidal (τ =1) extremes [Addison, Rao, Reedijk, van Rijn, J. & Verschoor (1984). J. Chem. Soc. Dalton Trans. pp. 1349–1356]. In addition to the aforementioned intramolecular hydrogen bond, pyrazole group N8—H8 also donates an intermolecular hydrogen bond to a neighbouring pyrazole pyridinic N atom N9iii [symmetry code: (iii) 2 - x, 2 - y, 1 - z] (Fig. 2). The resultant cyclic dimer of pyrazole rings is a common motif in pyrazole crystal chemistry (see e.g. Llamas-Saiz et al., 1994; Sobolev & White, 2004). The N—H···N and N—H···Cl hydrogen bonds combine to associate the cations and anions into alternating chains along the [1 0 1] vector, generated by the crystallographic inversion centres at 1/2, 1, 0 and 1, 1, 0.5 (Fig. 2). These chains are then further aggregated by the C4—H4···Cl19ii interaction into 2-D layers parallel to (0 1 0).
For related literature, see: Addison et al. (1984); Halcrow et al. (1996); Jones et al. (2006); Liu et al. (2004); Llamas-Saiz, Foces-Foces, Cano, Jiménez, Laynez, Meutermans, Elguero, Limbach & Aguilar-Parrilla (1994); Nieto et al. (2006); Pask, Camm, Bullen, Carr, Clegg, Kilner & Halcrow (2006); Pask, Camm, Kilner & Halcrow (2006); Pauling (1960); Reger et al. (1994); Renard et al. (2002); Sobolev & White (2004). Please provide all these references.
Data collection: COLLECT (Nonius, 1999); cell refinement: DENZO-SMN (Otwinowski & Minor, 1997); data reduction: DENZO-SMN; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: X-SEED (Barbour, 2003); software used to prepare material for publication: local program.
C13H17N4O+·Cl− | Z = 2 |
Mr = 280.76 | F(000) = 296 |
Triclinic, P1 | Dx = 1.291 Mg m−3 |
Hall symbol: -P 1 | Mo Kα radiation, λ = 0.71073 Å |
a = 9.0226 (1) Å | Cell parameters from 10651 reflections |
b = 9.1638 (2) Å | θ = 2.1–27.5° |
c = 9.7919 (2) Å | µ = 0.26 mm−1 |
α = 91.6357 (7)° | T = 150 K |
β = 95.5828 (7)° | Rectangular prism, colourless |
γ = 115.9693 (13)° | 0.60 × 0.51 × 0.35 mm |
V = 722.11 (2) Å3 |
Nonius KappaCCD area-detector diffractometer | 3204 independent reflections |
Radiation source: fine-focus sealed tube | 2590 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.092 |
Detector resolution: 9.091 pixels mm-1 | θmax = 27.5°, θmin = 2.1° |
ω and φ scans | h = −10→11 |
Absorption correction: multi-scan (SORTAV; Blessing, 1995) | k = −11→11 |
Tmin = 0.665, Tmax = 1.070 | l = −12→12 |
10651 measured reflections |
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)] = 0.054 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.156 | H-atom parameters constrained |
S = 1.07 | w = 1/[σ2(Fo2) + (0.0939P)2 + 0.0869P] where P = (Fo2 + 2Fc2)/3 |
3204 reflections | (Δ/σ)max < 0.001 |
175 parameters | Δρmax = 0.32 e Å−3 |
0 restraints | Δρmin = −0.39 e Å−3 |
C13H17N4O+·Cl− | γ = 115.9693 (13)° |
Mr = 280.76 | V = 722.11 (2) Å3 |
Triclinic, P1 | Z = 2 |
a = 9.0226 (1) Å | Mo Kα radiation |
b = 9.1638 (2) Å | µ = 0.26 mm−1 |
c = 9.7919 (2) Å | T = 150 K |
α = 91.6357 (7)° | 0.60 × 0.51 × 0.35 mm |
β = 95.5828 (7)° |
Nonius KappaCCD area-detector diffractometer | 3204 independent reflections |
Absorption correction: multi-scan (SORTAV; Blessing, 1995) | 2590 reflections with I > 2σ(I) |
Tmin = 0.665, Tmax = 1.070 | Rint = 0.092 |
10651 measured reflections |
R[F2 > 2σ(F2)] = 0.054 | 0 restraints |
wR(F2) = 0.156 | H-atom parameters constrained |
S = 1.07 | Δρmax = 0.32 e Å−3 |
3204 reflections | Δρmin = −0.39 e Å−3 |
175 parameters |
Experimental. Detector set at 30 mm from sample with different 2theta offsets 1 degree phi exposures for chi=0 degree settings 1 degree omega exposures for chi=90 degree settings |
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. No disorder was detected during refinement, and no restraints were applied. All non-H atoms were refined anisotropically. All H atoms were located in the difference map, but several of them (notably the methyl groups) did not refine satisfactorily when their positions were allowed to refine freely. Hence, in the final model all H atoms were placed in calculated positions and refined using a riding model. The pyridinium N1 and C6 sites were distinguished from their isotropic thermal parameters, and on the basis that N1 in the model donates a short hydrogen bond to Cl19 while C6 does not take part in hydrogen bonding. |
x | y | z | Uiso*/Ueq | ||
N1 | 1.00995 (18) | 1.23608 (18) | 0.03259 (16) | 0.0375 (4) | |
H1 | 0.9083 | 1.2271 | 0.0219 | 0.045* | |
C2 | 1.1167 (2) | 1.3256 (2) | −0.0529 (2) | 0.0440 (4) | |
H2 | 1.0822 | 1.3785 | −0.1223 | 0.053* | |
C3 | 1.2756 (2) | 1.3404 (2) | −0.0398 (2) | 0.0456 (5) | |
H3 | 1.3517 | 1.4028 | −0.1002 | 0.055* | |
C4 | 1.3232 (2) | 1.2635 (2) | 0.0623 (2) | 0.0450 (5) | |
H4 | 1.4328 | 1.2726 | 0.0724 | 0.054* | |
C5 | 1.2120 (2) | 1.1731 (2) | 0.15019 (19) | 0.0393 (4) | |
H5 | 1.2449 | 1.1207 | 0.2210 | 0.047* | |
C6 | 1.0510 (2) | 1.1596 (2) | 0.13364 (18) | 0.0343 (4) | |
C7 | 0.9246 (2) | 1.0642 (2) | 0.22032 (17) | 0.0345 (4) | |
N8 | 0.97461 (18) | 1.02065 (19) | 0.33875 (16) | 0.0382 (4) | |
N9 | 0.83143 (18) | 0.92777 (18) | 0.39042 (16) | 0.0373 (3) | |
H9 | 0.8268 | 0.8817 | 0.4685 | 0.045* | |
C10 | 0.6959 (2) | 0.9144 (2) | 0.30710 (18) | 0.0353 (4) | |
C11 | 0.7501 (2) | 1.0016 (2) | 0.19638 (18) | 0.0359 (4) | |
H11 | 0.6853 | 1.0166 | 0.1207 | 0.043* | |
N12 | 0.53424 (17) | 0.82319 (18) | 0.33567 (15) | 0.0383 (4) | |
H12 | 0.4528 | 0.8062 | 0.2705 | 0.046* | |
C13 | 0.4932 (2) | 0.7581 (2) | 0.45821 (19) | 0.0371 (4) | |
C14 | 0.3076 (2) | 0.6580 (2) | 0.46746 (19) | 0.0392 (4) | |
C15 | 0.2148 (2) | 0.7592 (2) | 0.4264 (2) | 0.0503 (5) | |
H15A | 0.1000 | 0.7028 | 0.4473 | 0.075* | |
H15B | 0.2150 | 0.7733 | 0.3276 | 0.075* | |
H15C | 0.2701 | 0.8661 | 0.4782 | 0.075* | |
C16 | 0.2427 (2) | 0.5028 (2) | 0.3698 (2) | 0.0449 (5) | |
H16A | 0.3068 | 0.4423 | 0.3941 | 0.067* | |
H16B | 0.2546 | 0.5325 | 0.2748 | 0.067* | |
H16C | 0.1253 | 0.4346 | 0.3784 | 0.067* | |
C17 | 0.2872 (3) | 0.6129 (3) | 0.6162 (2) | 0.0586 (6) | |
H17A | 0.3307 | 0.7124 | 0.6780 | 0.088* | |
H17B | 0.3485 | 0.5500 | 0.6413 | 0.088* | |
H17C | 0.1692 | 0.5475 | 0.6246 | 0.088* | |
O18 | 0.59996 (16) | 0.77827 (17) | 0.55327 (14) | 0.0465 (4) | |
Cl19 | 0.30815 (5) | 0.74128 (6) | 0.04736 (5) | 0.04462 (19) |
U11 | U22 | U33 | U12 | U13 | U23 | |
N1 | 0.0274 (7) | 0.0361 (8) | 0.0447 (8) | 0.0104 (6) | 0.0038 (6) | 0.0013 (6) |
C2 | 0.0388 (10) | 0.0383 (9) | 0.0489 (11) | 0.0110 (8) | 0.0078 (8) | 0.0043 (8) |
C3 | 0.0360 (10) | 0.0422 (10) | 0.0504 (11) | 0.0089 (8) | 0.0113 (8) | −0.0002 (8) |
C4 | 0.0281 (9) | 0.0457 (10) | 0.0546 (12) | 0.0106 (8) | 0.0068 (8) | −0.0074 (9) |
C5 | 0.0302 (9) | 0.0437 (10) | 0.0408 (10) | 0.0146 (7) | 0.0006 (7) | −0.0044 (8) |
C6 | 0.0293 (8) | 0.0320 (8) | 0.0370 (9) | 0.0102 (7) | 0.0018 (7) | −0.0036 (7) |
C7 | 0.0286 (8) | 0.0345 (8) | 0.0380 (9) | 0.0122 (7) | 0.0029 (7) | −0.0011 (7) |
N8 | 0.0278 (7) | 0.0420 (8) | 0.0409 (8) | 0.0121 (6) | 0.0037 (6) | 0.0038 (6) |
N9 | 0.0260 (7) | 0.0418 (8) | 0.0413 (8) | 0.0126 (6) | 0.0028 (6) | 0.0066 (6) |
C10 | 0.0273 (8) | 0.0356 (8) | 0.0406 (9) | 0.0125 (7) | 0.0014 (7) | −0.0021 (7) |
C11 | 0.0281 (8) | 0.0370 (9) | 0.0393 (9) | 0.0121 (7) | 0.0017 (7) | 0.0004 (7) |
N12 | 0.0246 (7) | 0.0429 (8) | 0.0411 (8) | 0.0099 (6) | 0.0008 (6) | 0.0043 (7) |
C13 | 0.0329 (9) | 0.0335 (8) | 0.0425 (10) | 0.0127 (7) | 0.0045 (7) | 0.0009 (7) |
C14 | 0.0306 (9) | 0.0368 (9) | 0.0440 (10) | 0.0091 (7) | 0.0064 (7) | 0.0021 (7) |
C15 | 0.0330 (10) | 0.0444 (11) | 0.0724 (14) | 0.0160 (8) | 0.0094 (9) | −0.0037 (10) |
C16 | 0.0375 (10) | 0.0339 (9) | 0.0554 (11) | 0.0090 (8) | 0.0051 (8) | 0.0011 (8) |
C17 | 0.0401 (11) | 0.0693 (14) | 0.0500 (12) | 0.0078 (10) | 0.0117 (9) | 0.0073 (10) |
O18 | 0.0332 (7) | 0.0529 (8) | 0.0448 (8) | 0.0119 (6) | −0.0006 (6) | 0.0082 (6) |
Cl19 | 0.0327 (3) | 0.0517 (3) | 0.0478 (3) | 0.0176 (2) | 0.00161 (19) | 0.0072 (2) |
N1—C6 | 1.343 (2) | C10—N12 | 1.389 (2) |
N1—C2 | 1.344 (2) | C11—H11 | 0.9500 |
N1—H1 | 0.8800 | N12—C13 | 1.366 (2) |
C2—C3 | 1.372 (3) | N12—H12 | 0.8800 |
C2—H2 | 0.9500 | C13—O18 | 1.220 (2) |
C3—C4 | 1.380 (3) | C13—C14 | 1.531 (2) |
C3—H3 | 0.9500 | C14—C17 | 1.532 (3) |
C4—C5 | 1.383 (3) | C14—C15 | 1.535 (3) |
C4—H4 | 0.9500 | C14—C16 | 1.538 (3) |
C5—C6 | 1.395 (2) | C15—H15A | 0.9800 |
C5—H5 | 0.9500 | C15—H15B | 0.9800 |
C6—C7 | 1.464 (2) | C15—H15C | 0.9800 |
C7—N8 | 1.338 (2) | C16—H16A | 0.9800 |
C7—C11 | 1.412 (2) | C16—H16B | 0.9800 |
N8—N9 | 1.356 (2) | C16—H16C | 0.9800 |
N9—C10 | 1.358 (2) | C17—H17A | 0.9800 |
N9—H9 | 0.8800 | C17—H17B | 0.9800 |
C10—C11 | 1.365 (3) | C17—H17C | 0.9800 |
C6—N1—C2 | 123.14 (16) | C13—N12—C10 | 124.38 (15) |
C6—N1—H1 | 118.4 | C13—N12—H12 | 117.8 |
C2—N1—H1 | 118.4 | C10—N12—H12 | 117.8 |
N1—C2—C3 | 119.82 (19) | O18—C13—N12 | 121.14 (16) |
N1—C2—H2 | 120.1 | O18—C13—C14 | 122.71 (17) |
C3—C2—H2 | 120.1 | N12—C13—C14 | 116.15 (15) |
C2—C3—C4 | 119.05 (18) | C13—C14—C17 | 107.90 (16) |
C2—C3—H3 | 120.5 | C13—C14—C15 | 109.60 (15) |
C4—C3—H3 | 120.5 | C17—C14—C15 | 110.49 (17) |
C3—C4—C5 | 120.29 (18) | C13—C14—C16 | 108.53 (14) |
C3—C4—H4 | 119.9 | C17—C14—C16 | 109.94 (17) |
C5—C4—H4 | 119.9 | C15—C14—C16 | 110.32 (16) |
C4—C5—C6 | 119.26 (19) | C14—C15—H15A | 109.5 |
C4—C5—H5 | 120.4 | C14—C15—H15B | 109.5 |
C6—C5—H5 | 120.4 | H15A—C15—H15B | 109.5 |
N1—C6—C5 | 118.43 (16) | C14—C15—H15C | 109.5 |
N1—C6—C7 | 118.64 (15) | H15A—C15—H15C | 109.5 |
C5—C6—C7 | 122.93 (17) | H15B—C15—H15C | 109.5 |
N8—C7—C11 | 112.09 (16) | C14—C16—H16A | 109.5 |
N8—C7—C6 | 118.10 (15) | C14—C16—H16B | 109.5 |
C11—C7—C6 | 129.75 (17) | H16A—C16—H16B | 109.5 |
C7—N8—N9 | 104.16 (14) | C14—C16—H16C | 109.5 |
N8—N9—C10 | 111.87 (15) | H16A—C16—H16C | 109.5 |
N8—N9—H9 | 124.1 | H16B—C16—H16C | 109.5 |
C10—N9—H9 | 124.1 | C14—C17—H17A | 109.5 |
N9—C10—C11 | 107.81 (15) | C14—C17—H17B | 109.5 |
N9—C10—N12 | 123.13 (16) | H17A—C17—H17B | 109.5 |
C11—C10—N12 | 129.05 (17) | C14—C17—H17C | 109.5 |
C10—C11—C7 | 104.07 (16) | H17A—C17—H17C | 109.5 |
C10—C11—H11 | 128.0 | H17B—C17—H17C | 109.5 |
C7—C11—H11 | 128.0 |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1···Cl19i | 0.88 | 2.15 | 2.9978 (16) | 163 |
C4—H4···Cl19ii | 0.95 | 2.76 | 3.6112 (18) | 149 |
N9—H9···N8iii | 0.88 | 2.33 | 2.936 (2) | 127 |
N9—H9···O18 | 0.88 | 2.11 | 2.655 (2) | 119 |
C11—H11···Cl19i | 0.95 | 2.78 | 3.5620 (19) | 140 |
N12—H12···Cl19 | 0.88 | 2.35 | 3.1799 (15) | 157 |
C16—H16B···Cl19 | 0.98 | 2.91 | 3.837 (2) | 157 |
Symmetry codes: (i) −x+1, −y+2, −z; (ii) −x+2, −y+2, −z; (iii) −x+2, −y+2, −z+1. |
Experimental details
Crystal data | |
Chemical formula | C13H17N4O+·Cl− |
Mr | 280.76 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 150 |
a, b, c (Å) | 9.0226 (1), 9.1638 (2), 9.7919 (2) |
α, β, γ (°) | 91.6357 (7), 95.5828 (7), 115.9693 (13) |
V (Å3) | 722.11 (2) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 0.26 |
Crystal size (mm) | 0.60 × 0.51 × 0.35 |
Data collection | |
Diffractometer | Nonius KappaCCD area-detector |
Absorption correction | Multi-scan (SORTAV; Blessing, 1995) |
Tmin, Tmax | 0.665, 1.070 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 10651, 3204, 2590 |
Rint | 0.092 |
(sin θ/λ)max (Å−1) | 0.650 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.054, 0.156, 1.07 |
No. of reflections | 3204 |
No. of parameters | 175 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.32, −0.39 |
Computer programs: COLLECT (Nonius, 1999), DENZO-SMN (Otwinowski & Minor, 1997), DENZO-SMN, SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), X-SEED (Barbour, 2003), local program.
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1···Cl19i | 0.88 | 2.15 | 2.9978 (16) | 162.8 |
C4—H4···Cl19ii | 0.95 | 2.76 | 3.6112 (18) | 148.9 |
N9—H9···N8iii | 0.88 | 2.33 | 2.936 (2) | 126.5 |
N9—H9···O18 | 0.88 | 2.11 | 2.655 (2) | 119.3 |
C11—H11···Cl19i | 0.95 | 2.78 | 3.5620 (19) | 139.8 |
N12—H12···Cl19 | 0.88 | 2.35 | 3.1799 (15) | 157.3 |
C16—H16B···Cl19 | 0.98 | 2.91 | 3.837 (2) | 157.2 |
Symmetry codes: (i) −x+1, −y+2, −z; (ii) −x+2, −y+2, −z; (iii) −x+2, −y+2, −z+1. |
The pyrazole ring is an attractive functionality for transition metal supramolecular chemistry in that it possesses a Lewis basic pyridinic N-donor and a Lewis acidic pyrrolic N—H group in adjacent sites. It can therefore be a ditopic ligand for metal salts, binding a metal cation and anion simultaneously, placing the two guests 3.5–4.5Å apart (Reger et al., 1994; Renard et al., 2002; Nieto et al., 2006). As a continuation of our own studies of metal-organic supramolecular chemistry of 5-substituted N—H pyrazoles (Liu et al., 2004; Renard et al., 2002 & 2006 and refs. therein), we have investigated the synthesis of bidentate ligands derived from 3-(pyrid-2-yl)-1H-pyrazole and their metal complexes (Pask, Camm, Kilner & Halcrow, 2006; Pask, Camm, Bullen et al., 2006; Jones et al., 2006 & 2007). During this work, we were interested in investigating how these ligands interact with anions in the absence of a metal cation and have examined the crystal structure of the hydrochloride salt of the title compound (I).
The asymmetric unit of (I) contains one formula unit, with the cation and anion both lying on general positions. All bond lengths and angles in the organic cation lie within the expected ranges. The pyridinium and pyrazole rings in (I) are not coplanar, having a dihedral angle of 17.45 (10)° between their least squares planes. The dihedral angle between the pyrazole and amido groups is smaller, at 10.48 (11)°. The conformation of (I), and of the related neutral compound N-(5-{pyridin-2-yl}pyrazol-3-yl)methylamide (II) (Pask, Camm, Kilner & Halcrow, 2006), differ in two important ways: a) the N atoms of the pyridine and pyrazole rings have an anti disposition in (I), but are syn to each other in (II) and b) the amide N—H group is anti to the pyrazole N atoms in (I). Since the amide bond has its usual transoid conformation, that facilitates the formation of an intramolecular hydrogen bond from the pyrazole ring to the amide carbonyl group, N8—H8···O18. However, in (II) these two groups are syn to each other, placing the carbonyl group on the opposite side of the pyrazole ring so that no intramolecular hydrogen bond is formed.
There are five intermolecular contacts to the Cl- ion Cl19 that are shorter than the sum of van der Waals radii of a Cl (1.8 Å) and H (1.2 Å) atom [Pauling (1960). The Nature of the Chemical Bond, 3rd ed. Ithaca: Cornell University Press.] (Fig. 2). These are: two N—H···Cl hydrogen bonds, from N12—H12 and N1i—H1i; and, three weaker C—H···Cl contacts from C11i—H11i, C4ii—H4ii and C16—H16B, with H···Cl = 2.76–2.91 Å [symmetry codes: (i) 1 - x, 2 - y, -z; (ii) 2 - x, 2 - y, -z]. The geometry about Cl19 is therefore is very distorted, with τ = 0.44 placing it midway between the square pyramidal (τ = 0) and trigonal bipyramidal (τ =1) extremes [Addison, Rao, Reedijk, van Rijn, J. & Verschoor (1984). J. Chem. Soc. Dalton Trans. pp. 1349–1356]. In addition to the aforementioned intramolecular hydrogen bond, pyrazole group N8—H8 also donates an intermolecular hydrogen bond to a neighbouring pyrazole pyridinic N atom N9iii [symmetry code: (iii) 2 - x, 2 - y, 1 - z] (Fig. 2). The resultant cyclic dimer of pyrazole rings is a common motif in pyrazole crystal chemistry (see e.g. Llamas-Saiz et al., 1994; Sobolev & White, 2004). The N—H···N and N—H···Cl hydrogen bonds combine to associate the cations and anions into alternating chains along the [1 0 1] vector, generated by the crystallographic inversion centres at 1/2, 1, 0 and 1, 1, 0.5 (Fig. 2). These chains are then further aggregated by the C4—H4···Cl19ii interaction into 2-D layers parallel to (0 1 0).