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

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COMMUNICATIONS
ISSN: 2056-9890

Racemic mefloquinium chloro­di­fluoro­acetate: crystal structure and Hirshfeld surface analysis

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aFundaçaö Oswaldo Cruz, Instituto de Tecnologia em Fármacos-Far Manguinhos, 21041-250 Rio de Janeiro, RJ, Brazil, bCHEMSOL, 1 Harcourt Road, Aberdeen AB15 5NY, Scotland, cDepartment of Physics, Bhavan's Sheth R. A. College of Science, Ahmedabad, Gujarat 380001, India, and dResearch Centre for Crystalline Materials, School of Science and Technology, Sunway University, 47500 Bandar Sunway, Selangor Darul Ehsan, Malaysia
*Correspondence e-mail: edwardt@sunway.edu.my

Edited by W. T. A. Harrison, University of Aberdeen, Scotland (Received 21 May 2018; accepted 23 May 2018; online 5 June 2018)

In the racemic title mol­ecular salt, C17H17F6N2O+·C2ClF2O3 (systematic name: 2-{[2,8-bis­(tri­fluoro­meth­yl)quinolin-4-yl](hy­droxy)meth­yl}piperidin-1-ium chloro­difluoro­acetate), the cation, which is protonated at the piperidine N atom, has the shape of the letter, L, with the piperidin-1-ium group being approximately orthogonal to the quinolinyl residue [the Cq—Cm—Cm–Na (q = quinolinyl; m = methine; a = ammonium) torsion angle is 177.79 (18)°]. An intra­molecular, charge-assisted ammonium-NHO(hydrox­yl) hydrogen bond ensures the hy­droxy-O and ammonium-N atoms lie to the same side of the mol­ecule [Oh—Cm—Cm—Na (h = hydrox­yl) = −59.7 (2)°]. In the crystal, charge-assisted hydroxyl-O—H⋯O(carboxyl­ate) and ammonium-N+—H⋯O(carboxyl­ate) hydrogen bonds generate a supra­molecular chain along [010]; the chain is consolidated by C—H⋯O inter­actions. Links between chains to form supra­molecular layers are of the type C—Cl⋯π(quinolinyl-C6) and the layers thus formed stack along the a-axis direction without directional inter­actions between them. The analysis of the calculated Hirshfeld surface points to the dominance of F⋯H contacts to the surface (40.8%) with significant contributions from F⋯F (10.5%) and C⋯F (7.0%) contacts.

1. Chemical context

Practical inter­est in compounds related to the title salt relates to the biological activity of Mefloquine ([2,8-bis­(tri­fluoro­meth­yl)quinolin-4-yl]-piperidin-2-yl­methanol). This arises when the racemic compound is reacted with HCl: the resulting salt, [(R*,S*)-(2-{[2,8-bis­(tri­fluoro­meth­yl)quinolin-4-yl](hy­droxy­meth­yl)piperidin-1-ium chloride is an anti-malarial drug, being effective against the causative agent, Plasmodium falciparum (Maguire et al., 2006[Maguire, J. D., Krisin, Marwoto, H., Richie, T. L., Fryauff, D. J. & Baird, J. K. (2006). Clin. Infect. Dis. 42, 1067-1072.]). Subsequently, diverse pharmaceutical potential has been disclosed, namely, as anti-bacterial (Mao et al., 2007[Mao, J., Wang, Y., Wan, B., Kozikowski, A. P. & Franzblau, S. G. (2007). ChemMedChem, 2, 1624-1630.]), anti-mycobacterial (Gonçalves et al., 2012[Gonçalves, R. S. B., Kaiser, C. R., Lourenço, M. C. S., Bezerra, F. A. F. M., de Souza, M. V. N., Wardell, J. L., Wardell, S. M. S. V., Henriques, M., das, G. M. de O. & Costa, T. (2012). Bioorg. Med. Chem. 20, 243-248.]) and as anti-cancer agents (Rodrigues et al., 2014[Rodrigues, F. A. R., Bomfim, I. da S., Cavalcanti, B. C., Pessoa, C., Goncalves, R. S. B., Wardell, J. L., Wardell, S. M. S. V. & de Souza, M. V. N. (2014). Chem. Biol. Drug Des. 83, 126-131.]). With the preceding facts in mind, it is not surprising that crystallography has played a key role in establishing the mol­ecular structures of this class of compound. Of particular crystallographic inter­est has been the characterization of a pair of kryptoracemates of mefloquinium salts in recent years (Jotani et al., 2016[Jotani, M. M., Wardell, J. L. & Tiekink, E. R. T. (2016). Z. Kristallogr. 231, 247-255.]; Wardell, Wardell et al., 2016[Wardell, J. L., Wardell, S. M. S. V. & Tiekink, E. R. T. (2016). Acta Cryst. E72, 872-877.]). The phenomenon of kryptoracemic behaviour has been reviewed in the last decade for both organic and coordination compounds (Fábián & Brock, 2010[Fábián, L. & Brock, C. P. (2010). Acta Cryst. B66, 94-103.]; Bernal & Watkins, 2015[Bernal, I. & Watkins, S. (2015). Acta Cryst. C71, 216-221.]). Briefly, for a material to be classified as kryptoracemic, it must satisfy the following crystallographic criteria: the space group must be one of the 65 Sohncke space groups, i.e. lacking an inversion centre, rotatory inversion axis, glide plane or a mirror plane, and Z′ would usually be greater than 1 (unless the mol­ecule lies on a rotation axis). In a continuation of structural studies of Mefloquine derivatives (Wardell et al., 2011[Wardell, S. M. S. V., Wardell, J. L., Skakle, J. M. S. & Tiekink, E. R. T. (2011). Z. Kristallogr. 226, 68-77.]; Wardell, Jotani et al., 2016[Wardell, J. L., Jotani, M. M. & Tiekink, E. R. T. (2016). Acta Cryst. E72, 1618-1627.]), herein the crystal and mol­ecular structures of the title salt, (I)[link], isolated from the 1:1 crystallization of racemic Mefloquine and chloro­difluoro­acetic acid are described along with an analysis of its calculated Hirshfeld surface.

[Scheme 1]

2. Structural commentary

The ions comprising the asymmetric unit of (I)[link] are shown in Fig. 1[link]. The illustrated cation has two chiral centres, namely R at C12 and S at C13, i.e. it is the [(+)-erythro-mefloquinium] isomer. However, it should be noted that the centrosymmetric unit cell has equal numbers of the other S-,R- enanti­omer, indicating that no resolution occurred during the crystallization experiment as has been observed in some of the earlier studies (see Chemical context). The pattern of hydrogen-bonding inter­actions involving the ammonium-N—H H atoms (see Supra­molecular features) provides confirmation of protonation at the N2 atom during crystallization and, therefore, the formation of a piperidin-1-ium cation. At the same time, delocalization of the π-electron density over the carboxyl­ate residue is confirmed by the equivalence of the C18—O2, O3 bond lengths, i.e. 2 × 1.238 (3) Å.

[Figure 1]
Figure 1
The mol­ecular structures of the ions comprising the asymmetric unit of (I)[link] showing the atom-labelling scheme and displacement ellipsoids at the 70% probability level. The dashed line signifies the N—H⋯O hydrogen bond.

The quinolinyl residue is not strictly planar with the r.m.s. deviation for the ten fitted non-H atoms being 0.0399 Å. This is also reflected in the dihedral angle formed between the (N1,C1–C4,C9) and (C4–C9) rings of 3.95 (15) Å. This aspect of the structure notwithstanding, the hydroxyl-O and ammonium-N atoms lie to opposite sides of the plane through the quinolinyl residue. This is seen in the value of the C2—C3—C12—O1 torsion angle of −20.3 (3)° cf. with that of 177.79 (18)° for C3—C12—C13—N2. The latter angle indicates the piperidin-1-ium residue is almost perpendicular to the quinolinyl residue with the methyl­ene-C17 group orientated towards the fused-ring system as seen in the gauche C3—C12—C13—C17 torsion angle of −60.7 (3)°. The observed conformation, whereby the hy­droxy-O and ammonium-N atoms lie to the same side of the mol­ecule [the O1—C12—C13—N2 torsion angle is −59.7 (2)°], is stabilized by an intra­molecular, charge-assisted ammonium-N2+—H⋯O1(hydrox­yl) hydrogen bond, Table 1[link]. In general terms, the shape of the cation is based on the letter, L.

Table 1
Hydrogen-bond geometry (Å, °)

Cg1 is the centroid of the (C4–C9) ring.

D—H⋯A D—H H⋯A DA D—H⋯A
N2—H2N⋯O1 0.89 (2) 2.34 (2) 2.722 (3) 106 (2)
O1—H1O⋯O3i 0.84 (2) 1.83 (2) 2.668 (3) 178 (3)
N2—H1N⋯O2 0.89 (2) 1.92 (2) 2.808 (3) 177 (2)
N2—H2N⋯O2ii 0.89 (2) 2.05 (2) 2.776 (3) 138 (2)
C5—H5⋯O3 0.95 2.45 3.367 (3) 162
C14—H14B⋯O1iii 0.99 2.39 3.362 (3) 166
C19—Cl1⋯Cg1iv 1.74 (1) 3.91 (1) 4.208 (3) 88 (1)
C10—F3⋯Cg1i 1.33 (1) 3.09 (1) 3.762 (3) 110 (1)
Symmetry codes: (i) x, y-1, z; (ii) -x+1, -y+1, -z+1; (iii) x, y+1, z; (iv) [-x+1, y+{\script{1\over 2}}, -z+{\script{1\over 2}}].

The anion in (I)[link] adopts a conformation where the Cl1 atom lies to one side of the O2C2 plane [r.m.s. deviation = 0.0089 Å], with the O2—C18—C19—Cl1 torsion angle being −93.3 (2)°, and the F7 and F8 atoms lying to the other side, the O2—C18—C19—F7, F8 torsion angles = 28.8 (3) and 146.3 (2)°, respectively. The conformation of the CClF2 residue in (I)[link] has been observed in the structure of the acid (Schilling & Mootz, 1995[Schilling, M. & Mootz, D. (1995). J. Fluor. Chem. 74, 255-258.]), the acid monohydrate and tetra­hydrate (Dahlems et al., 1996[Dahlems, T., Mootz, D. & Schilling, M. (1996). Z. Naturforsch. B, 51, 536-544.]) and in salts, e.g. with mono-protonated 1,4-di­aza­bicyclo­[2.2.2]octane (dabco), i.e. 4-aza-1-azoniabi­cyclo­[2.2.2]octane, for which three independent ion pairs comprise the asymmetric unit (Shi et al., 2013[Shi, X., Luo, J., Sun, Z., Li, S., Ji, C., Li, L., Han, L., Zhang, S., Yuan, D. & Hong, M. (2013). Cryst. Growth Des. 13, 2081-2086.]).

3. Supra­molecular features

The presence of charge-assisted hydroxyl-O—H⋯O(carb­oxyl­ate) and ammonium-N+—H⋯O(carboxyl­ate) hydrogen bonding features prominently in the mol­ecular packing of (I)[link] and leads to a supra­molecular chain propagating along the b-axis direction, Fig. 1[link]a and Table 1[link]. The ammonium-N+—H⋯O(carboxyl­ate) hydrogen bonds link two cations and two anions about a centre of inversion to form eight-membered {⋯HNH⋯O}2 synthons, Fig. 2[link]b. These are linked into a supra­molecular chain via hydroxyl-O—H⋯O(carboxyl­ate) hydrogen bonding, which leads to 18-membered {⋯OCO⋯HNC2OH}2 synthons, Fig. 2[link]b. In this scheme, the carboxyl­ate-O2 atom forms two hydrogen bonds. Additional stability to the supra­molecular chain is afforded by quinolinyl-C—H⋯O(carboxyl­ate) and methyl­ene-C—H⋯O(hydrox­yl) inter­actions, Table 1[link]. The chains are connected into layers via C—Cl⋯π(C4–C9) inter­actions, Table 1[link]. The layers stack along the a-axis direction without directional inter­actions between them, Fig. 2[link]c.

[Figure 2]
Figure 2
Mol­ecular packing in (I)[link]: (a) The supra­molecular chain along the b-axis direction, being sustained by O—H⋯O and N—H⋯O hydrogen bonding with non-participating H atoms omitted, (b) a simplified view of the chain highlighting the formation of the eight- and 18-membered supra­molecular synthons and (c) a view of the unit-cell contents shown in projection down the b-axis direction. The O—H⋯O, N—H⋯O and Cl⋯π inter­actions are shown as orange, blue and purple dashed lines, respectively.

4. Hirshfeld surface analysis

The Hirshfeld surface calculations for the title salt (I)[link] were performed in accord with an earlier publication on a related salt (Jotani et al., 2016[Jotani, M. M., Wardell, J. L. & Tiekink, E. R. T. (2016). Z. Kristallogr. 231, 247-255.]) and satisfactorily describe the additional influence of inter­atomic halogen–halogen, halogen–hydrogen and halogen⋯π contacts upon the packing. In addition to bright-red spots on the Hirshfeld surfaces mapped over dnorm in Fig. 3[link]a and b (labelled 1–3), corresponding to inter­molecular O—H⋯O, N—H⋯O and C—H⋯O inter­actions, Table 1[link], the presence of tiny faint-red spots, having labels S1–S4 in Fig. 3[link]c and d, indicate the influence of short inter­atomic H⋯H, F⋯H/H⋯F and F⋯F contacts [Table 2[link]; calculated in CrystalExplorer3.1 (Wolff et al., 2012[Wolff, S. K., Grimwood, D. J., McKinnon, J. J., Turner, M. J., Jayatilaka, D. & Spackman, M. A. (2012). CrystalExplorer. The University of Western Australia.])]. On the Hirshfeld surfaces mapped over electrostatic potential in Fig. 4[link], the donors and acceptors of inter­molecular hydrogen bonds are illustrated through the appearance of blue and red regions corresponding to positive and negative electrostatic potential, respectively. The presence of inter­molecular side-on C—halogen⋯π inter­actions namely C19—Cl1⋯π(C4–C9) and C10—F3⋯π(C4–C9), Table 1[link], are evident from the Hirshfeld surfaces mapped with shape-index property illustrated in Fig. 5[link].

Table 2
Summary of short inter­atomic contacts (Å) in (I)

Contact Distance Symmetry operation
H7⋯H15B 2.08 x, [{3\over 2}] − y, −[{1\over 2}] + z
F1⋯H16B 2.56 2 − x, 1 − y, 1 − z
F6⋯H15B 2.58 x, [{3\over 2}] − y, −[{1\over 2}] + z
F4⋯F5 2.903 (2) 2 − x, [{1\over 2}] + y, 1 − z
[Figure 3]
Figure 3
Views of the Hirshfeld surface of (I)[link] mapped over dnorm in the range −0.077 to +1.575 au, highlighting: (a) and (b) inter­molecular hydrogen bonds (with labels 1–3) by black-dashed lines, and (c) and (d) short inter­atomic H⋯H, F⋯H and F⋯F contacts (with labels S1–S4) by sky-blue, red and black dashed lines, respectively.
[Figure 4]
Figure 4
Two views of the Hirshfeld surface of (I)[link] mapped over the electrostatic potential in the range −0.133 to + 0.219 au. The red and blue regions represent negative and positive electrostatic potentials, respectively.
[Figure 5]
Figure 5
Two views of Hirshfeld surface of (I)[link] mapped over the shape-index property highlighting (a) C—Cl⋯π and (b) C—F⋯π contacts by yellow and black dotted lines, respectively

The overall two-dimensional fingerprint plot and those delineated (McKinnon et al., 2007[McKinnon, J. J., Jayatilaka, D. & Spackman, M. A. (2007). Chem. Commun. pp. 3814-3816.]) into H⋯H, O⋯H/H⋯O, F⋯H/H⋯F, F⋯F, C⋯F/F⋯C, Cl⋯H/H⋯Cl and C⋯Cl/Cl⋯C contacts are illustrated in Fig. 6[link]; the percentage contributions from the different inter­atomic contacts to the Hirshfeld surface are summarized in Table 3[link]. The formation of a salt between the piperidinium cation and carboxyl­ate anion through the charge-assisted hydrogen bonds and the presence of a number of H⋯Cl, F and O contacts result in the relatively small, i.e. 11.9%, contribution from H⋯H contacts to the Hirshfeld surface. Conversely, the relative high number of fluorine atoms lying on the surfaces of both the cation and anion, largely participating in F⋯H contacts, gives rise to their providing the greatest contribution, i.e. 40.8%, to the surface.

Table 3
Percentage contributions of inter­atomic contacts to the Hirshfeld surface for (I)

  Percentage contribution
Contact (I)
H⋯H 11.9
F⋯H/H⋯F 40.8
O⋯H/H⋯O 11.2
F⋯F 10.5
C⋯F/F⋯C 7.0
Cl⋯H/H⋯Cl 4.6
C⋯H/H⋯C 3.5
F⋯Cl/Cl⋯F 3.1
C⋯Cl/Cl⋯C 2.6
N⋯H/H⋯N 2.2
C⋯C 0.6
O⋯O 0.3
N⋯F/F⋯N 0.3
C⋯N/N⋯C 0.2
C⋯O/O⋯C 0.1
O⋯Cl/Cl⋯O 0.1
[Figure 6]
Figure 6
The full two-dimensional fingerprint plot for (I)[link] and those delineated into H⋯H, O⋯H/H⋯O, F⋯H/H⋯F, F⋯F, C⋯F/F⋯C, Cl⋯H/H⋯Cl and C⋯Cl/Cl⋯C contacts.

In the fingerprint plot delineated into H⋯H contacts in Fig. 6[link], the short inter­atomic H⋯H contact involving quinoline-H7 and methyl­ene-H15B, both derived from the cation, Table 2[link], is viewed as pencil-like tip at de + di ∼2.0 Å. In the fingerprint plot delineated into O⋯H/H⋯O contacts, the spikes associated with the N—H⋯O hydrogen bonds and C—H⋯O inter­actions are merged within the plot. The obvious feature in the plot is a pair of spikes with tips at de + di ∼1.8 Å, which correspond to the most dominant O—H⋯O hydrogen bond; this is also responsible for most of the points concentrated in the narrower region of spikes. The influence of short inter­atomic halogen–hydrogen and halogen–halogen contacts in the crystal, Table 2[link], is observed as a pair of forceps-like tips at de + di ∼2.5 Å (F⋯H) and 3.0 Å (Cl⋯H), and an arrow-shaped tip at de + di ∼2.8 Å in the fingerprint plots delineated into F⋯H/H⋯F, Cl⋯H/H⋯Cl and F⋯F contacts, respectively. The involvement of chloride and fluoride atoms in C-halogen⋯π contacts, Table 1[link], results in the small but significant percentage contribution from C⋯F/F⋯C and C⋯Cl/Cl⋯C contacts to the Hirshfeld surface, Table 3[link]. These inter­molecular contacts are also characterized as forceps-like and anchor-shaped distributions of points in the fingerprint plots delineated into the respective contacts, Fig. 6[link]. The small percentage contribution from other remaining inter­atomic contacts summarized in Table 3[link] have negligible effect on the packing in the crystal.

5. Database survey

Kryptoracemic behaviour is rare and is found in only 0.1% of all organic structures (Fábián & Brock, 2010[Fábián, L. & Brock, C. P. (2010). Acta Cryst. B66, 94-103.]). This observation clearly implies that 99.9% of racemic compounds, mol­ecules with meso symmetry and achiral mol­ecules will crystallize about a centre of inversion. Given there are fewer than 30 structures containing Mefloquine/derivatives of Mefloquine included in the Cambridge Structural Database (Groom et al., 2016[Groom, C. R., Bruno, I. J., Lightfoot, M. P. & Ward, S. C. (2016). Acta Cryst. B72, 171-179.]), the reporting of two kryptoracemates of mefloquinium cations in recent times (Jotani et al., 2016[Jotani, M. M., Wardell, J. L. & Tiekink, E. R. T. (2016). Z. Kristallogr. 231, 247-255.]; Wardell, Wardell et al., 2016[Wardell, J. L., Wardell, S. M. S. V. & Tiekink, E. R. T. (2016). Acta Cryst. E72, 872-877.]) suggests a higher than anti­cipated propensity for this phenomenon. The two examples were isolated from attempts at chiral resolution of Mefloquine with carb­oxy­lic acids. In the first of the two reported structures, the asymmetric unit comprised a pair of pseudo-enanti­omeric mefloquinium cations with the charge-balance provided by chloride and 4-fluoro­benzene­sulfonate anions (Jotani et al., 2016[Jotani, M. M., Wardell, J. L. & Tiekink, E. R. T. (2016). Z. Kristallogr. 231, 247-255.]). In the second example, again two mefloquinium cations are pseudo-racemic, with the charge-balance provided by two independent 3,3,3-tri­fluoro-2-meth­oxy-2-phenyl­propano­ate anions, i.e. (+)-PhC(CF3)(OMe)CO2 (Wardell, Wardell et al., 2016[Wardell, J. L., Wardell, S. M. S. V. & Tiekink, E. R. T. (2016). Acta Cryst. E72, 872-877.]). The appearance of kryptoracemic salts of mefloquinium with non-chiral and chiral counter-ions warrants further investigation into this comparatively rare behaviour in order to reveal the reasons for such crystallization outcomes.

6. Synthesis and crystallization

A solution of mefloquinium chloride (1 mmol) and sodium di­fluoro­choro­acetate (1 mmol) in EtOH (10ml) was refluxed for 20 mins. The reaction mixture was left at room temperature and after two days, colourless crystals of the title salt, (I)[link], were collected; M.p. 473–475 K.1H NMR (DMSO-d6) δ: 1.20–1.35 (2H, m), 1.55–1.75 (4H, m), 3.04 (1H, br t), 3.53 (1H, br d), 5.90 (1H, s), 6.94 (1H, br d), 8.01 (1H, t, J = 8.0 Hz), 8.13 (1H, s), 8.42 (1H, d, J = 8.02 Hz), 8.72 (1H, d, J = 8.0 Hz), 9.48 (1H, br s); N—H H not observed. 13C NMR (DMSO-d6) δ: 21.43 (2×), 21.59, 44.51, 58.90, 67.85, 1135.50. 121.17 (JC,F = 273.8 Hz), 121.21 (JC,F = 311.0 Hz), 123.64 (JC,F = 271.7.8 Hz), 126.37, 127.93 (JC,F = 29.2 Hz), 128.32, 128.68. 129.9 (JC,F = 5.2 Hz), 142.78, 146.73 (JC,F = 34.5 Hz), 150.97, 159.82 (JC,F = 25.2 Hz). 19F NMR (DMSO-d6) δ: −58.65, −58.84, −66.68. IR (cm−1) 3300–2400 (s,v br), 1662 (s).

7. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 4[link]. The carbon-bound H atoms were placed in calculated positions (C—H = 0.95–1.00 Å) and were included in the refinement in the riding-model approximation, with Uiso(H) set to 1.2Ueq(C). The O- and N-bound H atoms were refined with the distance restraints O—H = 0.84±0.01 and 0.88±0.01 Å, respectively, and with Uiso(H) = 1.5Ueq(O) and 1.2Ueq(N), respectively.

Table 4
Experimental details

Crystal data
Chemical formula C17H17F6N2O+·C2ClF2O2
Mr 508.79
Crystal system, space group Monoclinic, P21/c
Temperature (K) 120
a, b, c (Å) 14.4535 (4), 6.3387 (2), 23.9040 (8)
β (°) 104.214 (2)
V3) 2122.95 (12)
Z 4
Radiation type Mo Kα
μ (mm−1) 0.27
Crystal size (mm) 0.62 × 0.20 × 0.06
 
Data collection
Diffractometer Bruker–Nonius Roper CCD camera on κ-goniostat
Absorption correction Multi-scan (SADABS; Sheldrick, 2007[Sheldrick, G. M. (2007). SADABS. University of Göttingen, Germany.])
Tmin, Tmax 0.623, 0.746
No. of measured, independent and observed [I > 2σ(I)] reflections 19411, 4799, 3311
Rint 0.054
(sin θ/λ)max−1) 0.649
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.052, 0.142, 1.04
No. of reflections 4799
No. of parameters 307
No. of restraints 3
H-atom treatment H atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3) 0.94, −0.83
Computer programs: DENZO (Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]), COLLECT (Hooft, 1998[Hooft, R. W. W. (1998). COLLECT. Nonius BV, Delft, The Netherlands.]), SHELXS (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]), SHELXL2014/7 (Sheldrick, 2015[Sheldrick, G. M. (2015). Acta Cryst. C71, 3-8.]), ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]), DIAMOND (Brandenburg, 2006[Brandenburg, K. (2006). DIAMOND. Crystal Impact GbR, Bonn, Germany.]) and publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Supporting information


Computing details top

Data collection: COLLECT (Hooft, 1998); cell refinement: DENZO (Otwinowski & Minor, 1997) and COLLECT (Hooft, 1998); data reduction: DENZO (Otwinowski & Minor, 1997) and COLLECT (Hooft, 1998); program(s) used to solve structure: SHELXS (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014/7 (Sheldrick, 2015); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and DIAMOND (Brandenburg, 2006); software used to prepare material for publication: publCIF (Westrip, 2010).

2-{[2,8-Bis(trifluoromethyl)quinolin-4-yl](hydroxy)methyl}piperidin-1-ium chlorodifluoroacetate top
Crystal data top
C17H17F6N2O+·C2ClF2O2F(000) = 1032
Mr = 508.79Dx = 1.592 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
a = 14.4535 (4) ÅCell parameters from 17332 reflections
b = 6.3387 (2) Åθ = 2.9–27.5°
c = 23.9040 (8) ŵ = 0.27 mm1
β = 104.214 (2)°T = 120 K
V = 2122.95 (12) Å3Lath, colourless
Z = 40.62 × 0.20 × 0.06 mm
Data collection top
Bruker–Nonius Roper CCD camera on κ-goniostat
diffractometer
4799 independent reflections
Radiation source: Bruker–Nonius FR591 rotating anode3311 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.054
Detector resolution: 9.091 pixels mm-1θmax = 27.5°, θmin = 3.0°
φ & ω scansh = 1818
Absorption correction: multi-scan
(SADABS; Sheldrick, 2007)
k = 88
Tmin = 0.623, Tmax = 0.746l = 3130
19411 measured reflections
Refinement top
Refinement on F23 restraints
Least-squares matrix: fullHydrogen site location: mixed
R[F2 > 2σ(F2)] = 0.052H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.142 w = 1/[σ2(Fo2) + (0.0643P)2 + 1.2072P]
where P = (Fo2 + 2Fc2)/3
S = 1.04(Δ/σ)max < 0.001
4799 reflectionsΔρmax = 0.94 e Å3
307 parametersΔρmin = 0.83 e Å3
Special details top

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

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
F11.03148 (10)0.0703 (2)0.44433 (7)0.0399 (4)
F20.91566 (11)0.2736 (2)0.44998 (7)0.0359 (4)
F30.96175 (11)0.2572 (2)0.37136 (6)0.0366 (4)
F40.98916 (10)0.2960 (2)0.26696 (6)0.0349 (4)
F50.86497 (10)0.1175 (2)0.22440 (6)0.0336 (4)
F60.89009 (11)0.4242 (2)0.19252 (6)0.0375 (4)
O10.66219 (12)0.1694 (3)0.47757 (7)0.0279 (4)
H1O0.6352 (19)0.078 (4)0.4540 (10)0.042*
N10.88608 (13)0.1322 (3)0.34721 (8)0.0216 (4)
N20.64265 (14)0.5664 (3)0.51657 (8)0.0218 (4)
H1N0.5904 (12)0.601 (4)0.4899 (8)0.026*
H2N0.6290 (17)0.450 (3)0.5335 (10)0.026*
C10.87768 (16)0.0391 (3)0.39479 (9)0.0208 (5)
C20.81459 (16)0.1003 (4)0.42804 (10)0.0229 (5)
H20.81070.02190.46130.027*
C30.75848 (16)0.2756 (4)0.41176 (9)0.0208 (5)
C40.76778 (16)0.3898 (4)0.36220 (9)0.0210 (5)
C50.71864 (16)0.5805 (4)0.34349 (10)0.0234 (5)
H50.67600.63710.36420.028*
C60.73220 (17)0.6835 (4)0.29583 (10)0.0264 (5)
H60.70070.81400.28460.032*
C70.79223 (18)0.5987 (4)0.26324 (10)0.0272 (5)
H70.80030.67180.23010.033*
C80.83903 (16)0.4123 (4)0.27881 (10)0.0228 (5)
C90.83122 (15)0.3071 (4)0.33029 (9)0.0197 (5)
C100.94619 (17)0.1411 (4)0.41442 (10)0.0253 (5)
C110.89662 (18)0.3125 (4)0.24146 (10)0.0275 (5)
C120.68616 (16)0.3397 (4)0.44507 (10)0.0222 (5)
H120.62690.38990.41710.027*
C130.72279 (15)0.5153 (4)0.48924 (9)0.0210 (5)
H130.73670.64300.46810.025*
C140.66441 (19)0.7397 (4)0.56031 (10)0.0296 (6)
H14A0.61000.75820.57820.036*
H14B0.67380.87370.54120.036*
C150.75362 (19)0.6874 (4)0.60653 (10)0.0323 (6)
H15A0.74090.56450.62910.039*
H15B0.77050.80860.63320.039*
C160.83715 (19)0.6373 (4)0.58047 (11)0.0322 (6)
H16A0.89290.59400.61150.039*
H16B0.85500.76540.56190.039*
C170.81136 (17)0.4608 (4)0.53591 (10)0.0266 (5)
H17A0.86540.43640.51810.032*
H17B0.80010.32880.55540.032*
C180.49744 (17)0.7909 (4)0.39729 (10)0.0227 (5)
C190.41892 (18)0.8393 (4)0.34241 (11)0.0322 (6)
Cl10.43173 (7)0.68095 (18)0.28514 (4)0.0736 (3)
F70.33144 (11)0.8114 (3)0.35113 (8)0.0503 (5)
F80.42202 (13)1.0418 (3)0.32666 (8)0.0548 (5)
O20.47705 (12)0.6592 (3)0.43060 (7)0.0345 (4)
O30.57421 (12)0.8831 (3)0.40098 (7)0.0337 (4)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
F10.0265 (8)0.0331 (9)0.0508 (10)0.0024 (7)0.0085 (7)0.0049 (7)
F20.0410 (9)0.0275 (8)0.0417 (9)0.0037 (7)0.0150 (7)0.0167 (7)
F30.0443 (9)0.0331 (8)0.0319 (8)0.0130 (7)0.0087 (7)0.0002 (7)
F40.0263 (8)0.0453 (9)0.0343 (8)0.0014 (7)0.0098 (6)0.0052 (7)
F50.0402 (9)0.0323 (8)0.0296 (8)0.0005 (7)0.0111 (7)0.0070 (6)
F60.0478 (9)0.0450 (9)0.0241 (7)0.0091 (8)0.0172 (7)0.0081 (7)
O10.0352 (10)0.0257 (9)0.0256 (9)0.0125 (8)0.0129 (8)0.0029 (7)
N10.0215 (10)0.0203 (10)0.0209 (10)0.0036 (8)0.0011 (8)0.0009 (8)
N20.0257 (11)0.0225 (11)0.0166 (9)0.0019 (9)0.0039 (8)0.0009 (8)
C10.0228 (11)0.0176 (11)0.0202 (11)0.0037 (10)0.0016 (9)0.0002 (9)
C20.0258 (12)0.0234 (12)0.0186 (11)0.0041 (10)0.0040 (9)0.0027 (10)
C30.0219 (12)0.0217 (12)0.0180 (11)0.0059 (10)0.0035 (9)0.0026 (9)
C40.0209 (11)0.0235 (12)0.0171 (10)0.0023 (10)0.0021 (9)0.0006 (9)
C50.0256 (12)0.0230 (12)0.0210 (11)0.0011 (10)0.0044 (9)0.0027 (10)
C60.0320 (13)0.0250 (13)0.0203 (11)0.0041 (11)0.0026 (10)0.0009 (10)
C70.0347 (14)0.0290 (13)0.0169 (11)0.0007 (11)0.0047 (10)0.0043 (10)
C80.0232 (12)0.0243 (12)0.0201 (11)0.0033 (10)0.0037 (9)0.0027 (10)
C90.0181 (11)0.0206 (12)0.0185 (10)0.0038 (9)0.0007 (9)0.0003 (9)
C100.0239 (12)0.0245 (12)0.0257 (12)0.0036 (10)0.0024 (10)0.0023 (10)
C110.0304 (14)0.0294 (13)0.0236 (12)0.0004 (11)0.0080 (10)0.0044 (11)
C120.0246 (12)0.0229 (12)0.0202 (11)0.0040 (10)0.0072 (9)0.0000 (9)
C130.0222 (11)0.0227 (12)0.0187 (11)0.0025 (10)0.0062 (9)0.0001 (9)
C140.0440 (15)0.0227 (13)0.0233 (12)0.0020 (11)0.0108 (11)0.0034 (10)
C150.0474 (16)0.0285 (13)0.0187 (12)0.0084 (12)0.0036 (11)0.0049 (10)
C160.0377 (14)0.0314 (14)0.0229 (12)0.0103 (12)0.0011 (11)0.0012 (11)
C170.0281 (13)0.0261 (13)0.0228 (12)0.0036 (11)0.0012 (10)0.0020 (10)
C180.0257 (12)0.0232 (12)0.0210 (11)0.0006 (10)0.0089 (10)0.0049 (10)
C190.0324 (14)0.0314 (15)0.0304 (13)0.0004 (12)0.0034 (11)0.0044 (11)
Cl10.0796 (6)0.0932 (8)0.0373 (5)0.0119 (6)0.0064 (4)0.0325 (5)
F70.0260 (8)0.0627 (12)0.0579 (11)0.0023 (8)0.0018 (7)0.0159 (9)
F80.0594 (11)0.0444 (11)0.0564 (11)0.0056 (9)0.0060 (9)0.0235 (9)
O20.0284 (9)0.0451 (11)0.0310 (10)0.0012 (9)0.0093 (8)0.0134 (9)
O30.0320 (10)0.0380 (10)0.0316 (10)0.0117 (9)0.0085 (8)0.0078 (8)
Geometric parameters (Å, º) top
F1—C101.342 (3)C7—C81.367 (3)
F2—C101.344 (3)C7—H70.9500
F3—C101.329 (3)C8—C91.428 (3)
F4—C111.331 (3)C8—C111.502 (3)
F5—C111.346 (3)C12—C131.536 (3)
F6—C111.350 (3)C12—H121.0000
O1—C121.422 (3)C13—C171.517 (3)
O1—H1O0.835 (10)C13—H131.0000
N1—C11.313 (3)C14—C151.514 (4)
N1—C91.365 (3)C14—H14A0.9900
N2—C141.496 (3)C14—H14B0.9900
N2—C131.498 (3)C15—C161.522 (4)
N2—H1N0.888 (10)C15—H15A0.9900
N2—H2N0.886 (10)C15—H15B0.9900
C1—C21.403 (3)C16—C171.527 (3)
C1—C101.509 (3)C16—H16A0.9900
C2—C31.374 (3)C16—H16B0.9900
C2—H20.9500C17—H17A0.9900
C3—C41.423 (3)C17—H17B0.9900
C3—C121.517 (3)C18—O21.238 (3)
C4—C51.418 (3)C18—O31.238 (3)
C4—C91.429 (3)C18—C191.540 (3)
C5—C61.368 (3)C19—F81.341 (3)
C5—H50.9500C19—F71.343 (3)
C6—C71.407 (3)C19—Cl11.744 (3)
C6—H60.9500
C12—O1—H1O107 (2)F6—C11—C8111.3 (2)
C1—N1—C9116.79 (19)O1—C12—C3112.03 (19)
C14—N2—C13114.28 (19)O1—C12—C13105.27 (17)
C14—N2—H1N108.3 (17)C3—C12—C13112.92 (18)
C13—N2—H1N110.7 (17)O1—C12—H12108.8
C14—N2—H2N108.9 (17)C3—C12—H12108.8
C13—N2—H2N107.6 (16)C13—C12—H12108.8
H1N—N2—H2N107 (2)N2—C13—C17109.37 (18)
N1—C1—C2125.3 (2)N2—C13—C12106.47 (17)
N1—C1—C10114.6 (2)C17—C13—C12115.3 (2)
C2—C1—C10120.1 (2)N2—C13—H13108.5
C3—C2—C1118.9 (2)C17—C13—H13108.5
C3—C2—H2120.5C12—C13—H13108.5
C1—C2—H2120.5N2—C14—C15110.1 (2)
C2—C3—C4118.5 (2)N2—C14—H14A109.6
C2—C3—C12120.2 (2)C15—C14—H14A109.6
C4—C3—C12121.3 (2)N2—C14—H14B109.6
C5—C4—C3123.7 (2)C15—C14—H14B109.6
C5—C4—C9118.8 (2)H14A—C14—H14B108.1
C3—C4—C9117.5 (2)C14—C15—C16111.5 (2)
C6—C5—C4120.4 (2)C14—C15—H15A109.3
C6—C5—H5119.8C16—C15—H15A109.3
C4—C5—H5119.8C14—C15—H15B109.3
C5—C6—C7120.8 (2)C16—C15—H15B109.3
C5—C6—H6119.6H15A—C15—H15B108.0
C7—C6—H6119.6C15—C16—C17110.9 (2)
C8—C7—C6120.7 (2)C15—C16—H16A109.5
C8—C7—H7119.6C17—C16—H16A109.5
C6—C7—H7119.6C15—C16—H16B109.5
C7—C8—C9120.0 (2)C17—C16—H16B109.5
C7—C8—C11120.8 (2)H16A—C16—H16B108.1
C9—C8—C11119.2 (2)C13—C17—C16111.3 (2)
N1—C9—C4122.8 (2)C13—C17—H17A109.4
N1—C9—C8118.1 (2)C16—C17—H17A109.4
C4—C9—C8119.0 (2)C13—C17—H17B109.4
F3—C10—F1106.86 (19)C16—C17—H17B109.4
F3—C10—F2106.77 (19)H17A—C17—H17B108.0
F1—C10—F2105.88 (19)O2—C18—O3128.6 (2)
F3—C10—C1113.66 (19)O2—C18—C19116.1 (2)
F1—C10—C1111.04 (19)O3—C18—C19115.3 (2)
F2—C10—C1112.17 (19)F8—C19—F7105.5 (2)
F4—C11—F5107.2 (2)F8—C19—C18111.2 (2)
F4—C11—F6106.65 (19)F7—C19—C18111.5 (2)
F5—C11—F6105.81 (19)F8—C19—Cl1108.24 (18)
F4—C11—C8113.7 (2)F7—C19—Cl1109.36 (19)
F5—C11—C8111.7 (2)C18—C19—Cl1110.85 (18)
C9—N1—C1—C22.6 (3)N1—C1—C10—F2158.96 (19)
C9—N1—C1—C10174.73 (19)C2—C1—C10—F223.6 (3)
N1—C1—C2—C32.4 (3)C7—C8—C11—F4117.4 (2)
C10—C1—C2—C3174.7 (2)C9—C8—C11—F464.5 (3)
C1—C2—C3—C40.9 (3)C7—C8—C11—F5121.2 (2)
C1—C2—C3—C12177.0 (2)C9—C8—C11—F557.0 (3)
C2—C3—C4—C5175.6 (2)C7—C8—C11—F63.1 (3)
C12—C3—C4—C56.5 (3)C9—C8—C11—F6175.05 (19)
C2—C3—C4—C93.7 (3)C2—C3—C12—O120.3 (3)
C12—C3—C4—C9174.2 (2)C4—C3—C12—O1157.6 (2)
C3—C4—C5—C6179.0 (2)C2—C3—C12—C1398.3 (2)
C9—C4—C5—C60.3 (3)C4—C3—C12—C1383.8 (3)
C4—C5—C6—C72.4 (4)C14—N2—C13—C1756.2 (3)
C5—C6—C7—C80.6 (4)C14—N2—C13—C12178.61 (18)
C6—C7—C8—C93.3 (4)O1—C12—C13—N259.7 (2)
C6—C7—C8—C11174.9 (2)C3—C12—C13—N2177.79 (18)
C1—N1—C9—C40.6 (3)O1—C12—C13—C1761.8 (2)
C1—N1—C9—C8179.8 (2)C3—C12—C13—C1760.7 (3)
C5—C4—C9—N1175.6 (2)C13—N2—C14—C1555.7 (3)
C3—C4—C9—N13.7 (3)N2—C14—C15—C1654.0 (3)
C5—C4—C9—C83.5 (3)C14—C15—C16—C1755.1 (3)
C3—C4—C9—C8177.2 (2)N2—C13—C17—C1655.3 (3)
C7—C8—C9—N1173.9 (2)C12—C13—C17—C16175.15 (19)
C11—C8—C9—N17.9 (3)C15—C16—C17—C1356.0 (3)
C7—C8—C9—C45.3 (3)O2—C18—C19—F8146.3 (2)
C11—C8—C9—C4172.9 (2)O3—C18—C19—F836.6 (3)
N1—C1—C10—F337.7 (3)O2—C18—C19—F728.8 (3)
C2—C1—C10—F3144.8 (2)O3—C18—C19—F7154.0 (2)
N1—C1—C10—F182.8 (2)O2—C18—C19—Cl193.3 (2)
C2—C1—C10—F194.7 (3)O3—C18—C19—Cl183.9 (2)
Hydrogen-bond geometry (Å, º) top
Cg1 is the centroid of the (C4–C9) ring.
D—H···AD—HH···AD···AD—H···A
N2—H2N···O10.89 (2)2.34 (2)2.722 (3)106 (2)
O1—H1O···O3i0.84 (2)1.83 (2)2.668 (3)178 (3)
N2—H1N···O20.89 (2)1.92 (2)2.808 (3)177 (2)
N2—H2N···O2ii0.89 (2)2.05 (2)2.776 (3)138 (2)
C5—H5···O30.952.453.367 (3)162
C14—H14B···O1iii0.992.393.362 (3)166
C19—Cl1···Cg1iv1.74 (1)3.91 (1)4.208 (3)88 (1)
C10—F3···Cg1i1.33 (1)3.09 (1)3.762 (3)110 (1)
Symmetry codes: (i) x, y1, z; (ii) x+1, y+1, z+1; (iii) x, y+1, z; (iv) x+1, y+1/2, z+1/2.
Summary of short interatomic contacts (Å) in (I) top
ContactDistanceSymmetry operation
H7···H15B2.08x, 3/2 - y, -1/2 + z
F1···H16B2.562 - x, 1 - y, 1 - z
F6···H15B2.58x, 3/2 - y, -1/2 + z
F4···F52.903 (2)2 - x, 1/2 + y, 1 - z
Percentage contributions of interatomic contacts to the Hirshfeld surface for (I) top
Percentage contribution
Contact(I)
H···H11.9
F···H/H···F40.8
O···H/H···O11.2
F···F10.5
C···F/F···C7.0
Cl···H/H···Cl4.6
C···H/H···C3.5
F···Cl/Cl···F3.1
C···Cl/Cl···C2.6
N···H/H···N2.2
C···C0.6
O···O0.3
N···F/F···N0.3
C···N/N···C0.2
C···O/O···C0.1
O···Cl/Cl···O0.1
 

Footnotes

Additional correspondence author, e-mail: j.wardell@abdn.ac.uk.

Acknowledgements

The use of the EPSRC X-ray crystallographic service at the University of Southampton, England, and the valuable assistance of the staff there is gratefully acknowledged.

Funding information

JLW acknowledges support from CNPq (Brazil).

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