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ISSN: 2056-9890
Volume 76| Part 4| April 2020| Pages 552-556
https://doi.org/10.1107/S2056989020003643

Synthesis and crystal structures of two 1,3-di(alk­yl­oxy)-2-(methyl­sulfan­yl)imidazolium tetra­fluorido­borates

CROSSMARK_Color_square_no_text.svg
Thomas Gelbrich,a* Martin Lampl,b Gerhard Laus,b‡ Volker Kahlenberg,c Hubert Huppertzb and Herwig Schottenbergerb

aUniversity of Innsbruck, Institute of Pharmacy, Innrain 52, 6020 Innsbruck, Austria, bUniversity of Innsbruck, Faculty of Chemistry and Pharmacy, Innrain 80-82, 6020 Innsbruck, Austria, and cUniversity of Innsbruck, Institute of Mineralogy and Petrography, Innrain 52, 6020 Innsbruck, Austria
*Correspondence e-mail: thomas.gelbrich@uibk.ac.at

Edited by M. Weil, Vienna University of Technology, Austria (Received 18 February 2020; accepted 11 March 2020; online 17 March 2020)

Two salts were prepared by methyl­ation of the respective imidazoline-2-thione at the sulfur atom, using Meerwein's salt (tri­methyl­oxonium tetra­fluorido­borate) in CH2Cl2. 1,3-Dimeth­oxy-2-(methyl­sulfan­yl)imidazolium tetra­fluorido­borate (1), C6H11N2O2S+·BF4−, displays a syn conformation of its two meth­oxy groups relative to each other whereas the two benz­yloxy groups present in 1,3-dibenz­yloxy-2-(methyl­sulfan­yl)imidazolium tetra­fluorido­borate (2), C18H19N2O2S+·BF4−, adopt an anti conformation. In the mol­ecules of 1 and 2, the methyl­sulfanyl group is rotated out of the plane of the respective heterocyclic ring. In both crystal structures, inter­molecular inter­actions are dominated by C—H⋯F—B contacts, leading to three-dimensional networks. The tetra­fluorido­borate counter-ion of 2 is disordered over three orientations (occupancy ratio 0.42:0.34:0.24), which are related by rotation about one of the B—F bonds.

CCDC references: 1989707; 1989706

Similar articles

1. Chemical context

2-(Methyl­thio)­imidazolium salts have attracted great inter­est because of their reactive properties. Compounds belonging to this class can be converted into important derivatives with useful biological activity, i.e. as anti-filarial agents (Link et al., 1990[Link, H., Klötzer, W., Karpitschka, E. M., Montavon, M., Müssner, R. & Singewald, N. (1990). Angew. Chem. 102, 559-560.]). Furthermore, they have been used as precursors for the synthesis of remote N-heterocyclic carbene complexes (rNHC) (Patel et al., 2018[Patel, N., Arfeen, M., Sood, R., Khullar, S., Chakraborti, A. K., Mandal, S. K. & Bharatam, P. V. (2018). Chem. Eur. J. 24, 6418-6425.]), as tunable alkyl­ating reagents (Guterman et al., 2018[Guterman, R., Miao, H. & Antonietti, M. (2018). J. Org. Chem. 83, 684-689.]) or as coupling reagents for the formation of bis­(2-imidazol­yl)methyl­ium salts (Kuhn et al., 1993[Kuhn, N., Bohnen, H., Kratz, T. & Henkel, G. (1993). Liebigs Ann. Chem. pp. 1149-1151.]; Fürstner et al., 2008[Fürstner, A., Alcarazo, M., Goddard, R. & Lehmann, C. W. (2008). Angew. Chem. Int. Ed. 47, 3210-3214.]).

The S-methyl­ation of thio­nes, typically with methyl iodide or Meerwein's salt (tri­methyl­oxonium tetra­fluorido­borate), is straightforward. The title compounds 1 and 2 were prepared by methyl­ation of 1,3-di­meth­oxy­imidazoline-2-thione (Laus et al., 2013[Laus, G., Kahlenberg, V., Wurst, K., Müller, T., Kopacka, H. & Schottenberger, H. (2013). Z. Naturforsch. Teil B, 68, 1239-1252.]) and 1,3-di(benz­yloxy)imidazoline-2-thione (Laus et al., 2016[Laus, G., Kostner, M. E., Kahlenberg, V. & Schottenberger, H. (2016). Z. Naturforsch. Teil B, 71, 997-1003.]), respectively, using Meerwein's salt in CH2Cl2. An analogous procedure was applied by Williams et al. (1994[Williams, D. J., Ly, T. A., Mudge, J. W., VanDerveer, D. & Jones, R. L. (1994). Inorg. Chim. Acta, 218, 133-138.]) for the synthesis of the classic 1,3-dimethyl-2-(methyl­sulfan­yl)imidazolium iodide.

2. Structural commentary

In the organic cation of 1, the two meth­oxy groups adopt a syn conformation relative to each other, and the methyl­sulfanyl group is anti to each of the meth­oxy groups (Fig. 1[link]). In contrast, the structurally related mol­ecule of 1,3-di­meth­oxy­imidazoline-2-thione displays an anti conformation of its meth­oxy groups (Laus et al., 2013[Laus, G., Kahlenberg, V., Wurst, K., Müller, T., Kopacka, H. & Schottenberger, H. (2013). Z. Naturforsch. Teil B, 68, 1239-1252.]). The two N—OMe fragments of 1 form dihedral angles with the mean plane of the imidazole ring of 82.3 (2)° (for the ring involving O1 and C4) and of 76.8 (1)° (for the ring involving O2 and C5). The methyl­sulfanyl group (S1–C6) is rotated out of the heterocyclic plane and forms a dihedral angle of 62.5 (1)° with the mean plane of the heterocycle defined by atoms N1, C1, N2, C2, and C3.

[Scheme 1]
[Figure 1]
Figure 1
The ion pair structure of methyl­sulfanyl salt 1, showing displacement ellipsoids drawn at the 50% probability level and hydrogen atoms drawn as spheres of arbitrary size.

Similar to 1, the methyl­sulfanyl group (S1–C18) of 2 is rotated out of the plane of the heterocycle and forms a dihedral angle of 78.6 (1)° with the mean plane defined by the imidazole ring atoms (N1, C1, N2, C2, C3). The arrangement of the two benz­yloxy moieties in the cation of 2 relative to each other is anti (Fig. 2[link]). They adopt distinct conformations, which is illustrated by the different values of the torsion angles N1—O1—C4—C5 = −174.2 (2)° and N2—O2—C11—C12 = 95.5 (2)°. The two benzene ring planes are inclined by 17.34 (9)° for C5–C10 and by 30.6 (1)° for C12–C17 relative to the plane of the central heterocycle. The tetra­fluorido­borate counter-ion of 2 is disordered over three orientations (occupancy ratio 0.42:0.34:0.24), which are related by a rotation about the B1—F1 bond (Fig. 3[link]).

[Figure 2]
Figure 2
The ion pair structure of methyl­sulfanyl salt 2, showing displacement ellipsoids drawn at the 50% probability level and hydrogen atoms drawn as spheres of arbitrary size. Only one of the three different orientations of the disordered BF4− anion is shown.
[Figure 3]
Figure 3
Disorder of the tetra­fluorido­borate anion in the structure of 2. The disorder components A (F2A, F3A, F4A), B (F2B, F3B, F4B) and C (F2C, F3C, F4C) are related by a rotation about the B1—F1 bond.

The heterocycleC—S bond lengths [1.722 (2) and 1.721 (3) Å for 1 and 2, respectively] determined in this study are in good agreement with the mean value (1.735 Å) calculated from 82 pertinent C—S distances compiled in the Cambridge Structural Database (selection criterion R1 < 0.10; Groom et al., 2016[Groom, C. R., Bruno, I. J., Lightfoot, M. P. & Ward, S. C. (2016). Acta Cryst. B72, 171-179.]).

3. Supra­molecular features

Both structures display multiple C—H⋯F—B contacts which cross-link the ion pairs and result in three-dimensional networks (Tables 1[link] and 2[link]). In the crystal structure of 1, the two most important of these inter­actions, C2—H2⋯F3(−x + [{1\over 2}], y − [{1\over 2}], −z + [{3\over 2}]) and C3—H3⋯F2(x + [{1\over 2}], −y + [{1\over 2}], z + [{1\over 2}]), involve the two imidazole CH groups and yield a substructure with an R44(14) motif (Etter et al., 1990[Etter, M. C., MacDonald, J. C. & Bernstein, J. (1990). Acta Cryst. B46, 256-262.]; Bernstein et al., 1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]) (Fig. 4[link]). Moreover, the two meth­oxy groups are involved in this type of hydrogen bonding, albeit with weaker strength as can be seen in the longer H⋯F contacts (Table 1[link]). In the di(benz­yloxy) salt 2, each of the three disorder components of the anion gives rise to a specific set of C—H⋯F—B contacts. Fig. 5[link] shows the most significant inter­actions for one of the BF4− components, which also involves one heterocyclic hydrogen (H2) as well as both methyl­ene (H4A, H4B; H11A) and two aromatic hydrogen atoms (H8, H10) of the cation. In contrast to 1, the methyl­sulfanyl group (H18C) is also involved in hydrogen-bonding inter­actions.

Table 1
Hydrogen-bond geometry (Å, °) for 1[link]

D—H⋯A D—H H⋯A D⋯A D—H⋯A
C2—H2⋯F3i 0.95 2.26 3.137 (3) 154
C2—H2⋯F2i 0.95 2.51 3.361 (3) 150
C3—H3⋯F2ii 0.95 2.33 3.207 (3) 153
C4—H4B⋯F3iii 0.98 2.61 3.408 (3) 139
C4—H4B⋯F4iii 0.98 2.52 3.487 (3) 168
C4—H4C⋯F2 0.98 2.46 3.418 (3) 167
C5—H5A⋯F3 0.98 2.54 3.519 (3) 177
Symmetry codes: (i) [-x+{\script{1\over 2}}, y-{\script{1\over 2}}, -z+{\script{3\over 2}}]; (ii) [x+{\script{1\over 2}}, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]; (iii) [x+{\script{1\over 2}}, -y+{\script{1\over 2}}, z-{\script{1\over 2}}].

Table 2
Hydrogen-bond geometry (Å, °) for 2[link]

D—H⋯A D—H H⋯A D⋯A D—H⋯A
C2—H2⋯F2Ai 0.95 2.28 3.200 (13) 162
C2—H2⋯F3Bi 0.95 2.55 3.302 (14) 136
C2—H2⋯F2Ci 0.95 2.07 2.936 (10) 150
C4—H4B⋯F2B 0.99 2.52 3.472 (17) 162
C4—H4A⋯F3Bi 0.99 2.50 3.183 (13) 126
C4—H4A⋯F2Ci 0.99 2.56 3.39 (3) 141
C4—H4B⋯F4C 0.99 2.61 3.522 (19) 153
C8—H8⋯F1ii 0.95 2.54 3.317 (4) 139
C10—H10⋯F3Bi 0.95 2.46 3.282 (12) 145
C11—H11A⋯F3Aiii 0.99 2.27 3.247 (13) 167
C11—H11A⋯F3Ciii 0.99 2.40 3.279 (15) 148
C18—H18C⋯F3Aiii 0.98 2.62 3.409 (14) 138
Symmetry codes: (i) [-x+1, y+{\script{1\over 2}}, -z+1]; (ii) [-x+1, y, z+{\script{1\over 2}}]; (iii) x-1, y, z.
[Figure 4]
Figure 4
Crystal packing of compound 1. Dashed lines represent the shortest inter­molecular C—H⋯F inter­actions. [Symmetry codes: (i) −x + [{1\over 2}], y − [{1\over 2}], −z + [{3\over 2}]; (ii) x + [{1\over 2}], −y + [{1\over 2}], z + [{1\over 2}].]
[Figure 5]
Figure 5
Crystal packing of compound 2, viewed along the a axis. Dashed lines represent the shortest inter­molecular C—H⋯F inter­actions involving the disorder component B of the tetra­fluorido­borate anion. [Symmetry codes: (i) −x + 1, y, z + [{1\over 2}]; (ii) −x + 1, y + [{1\over 2}], −z + 1.]

4. Database survey

In addition to the classic 1,3-di­methyl­imidazolium-2-methyl­sulfanylimidazolium iodide (Williams et al., 1994[Williams, D. J., Ly, T. A., Mudge, J. W., VanDerveer, D. & Jones, R. L. (1994). Inorg. Chim. Acta, 218, 133-138.]), the Cambridge Structural Database (Version 5.41 November 2019; Groom et al., 2016[Groom, C. R., Bruno, I. J., Lightfoot, M. P. & Ward, S. C. (2016). Acta Cryst. B72, 171-179.]) comprises a number of more unusual representatives such as very bulky 1,3-diaryl-2-phenyl­thio­imidazolium (Inés et al., 2010[Inés, B., Holle, S., Goddard, R. & Alcarazo, M. (2010). Angew. Chem. Int. Ed. 49, 8389-8391.]) and 1,3-diaryl-2-methyl­sulfanylimidazolium salts (Liu et al., 2017[Liu, L. L., Zhu, D., Cao, L. L. & Stephan, D. W. (2017). Dalton Trans. 46, 3095-3099.]). These compounds are suitable precursors for the generation of exotic N-heterocyclic carbene–chalcogen cations.

Noteworthy is also the structure of a stabilized imidazoline-2-thione methyl­ide (Arduengo & Burgess, 1976[Arduengo, A. J. & Burgess, E. M. (1976). J. Am. Chem. Soc. 98, 5021-5023.]). The attachment of a fluorine-containing group to a given mol­ecule may enhance certain properties and therefore widen the range of potential applications. For example, salts bearing S—CF3 groups (Mizuta et al., 2016[Mizuta, S., Kitamura, K., Nishi, K., Hashimoto, R., Usui, T. & Chiba, K. (2016). RSC Adv. 6, 43159-43162.]) have been found to be effective electrophilic phase-transfer catalysts. Additionally, the introduction of perfluoro­alkyl­thio groups (Hummel et al., 2017[Hummel, M., Markiewicz, M., Stolte, S., Noisternig, M. E., Braun, D., Gelbrich, T., Griesser, U. J., Partl, G., Naier, B., Wurst, K., Krüger, B., Kopacka, H., Laus, G., Huppertz, H. & Schottenberger, H. (2017). Green Chem. 19, 3225-3237.]) resulted in improved surfactant properties.

5. Synthesis and crystallization

1,3-Dimeth­oxy-2-methyl­sulfanylimidazolium tetra­fluorido­borate (1): Tri­methyl­oxonium tetra­fluorido­borate (0.51 g, 3.44 mmol) was added to a solution of 1,3-di­meth­oxy­imidazoline-2-thione (0.50 g, 3.12 mmol) in CH2Cl2 (20 ml). The mixture was stirred for 18 h at room temperature, then the solvent was evaporated. The residue was dissolved in EtOH (3 ml) and cooled at 277 K, forming colourless single crystals. The crystalline product was filtered, washed with Et2O (2 × 5 ml) and dried. Yield: 0.53 g, m.p. 363 K. 1H NMR (300 MHz, DMSO-d6): δ 2.72 (s, 3H), 4.25 (s, 6H), 8.43 (s, 2H) ppm 13C NMR (75 MHz, DMSO-d6): δ 16.3, 68.9 (2C), 118.0 (2C), 135.7 ppm IR (neat): ν 3153 (m), 3134 (m), 1552 (m), 1445 (m), 1287 (w), 1043 (vs), 1018 (vs), 937 (s), 754 (s), 734 (s), 689 (m), 672 (m), 619 (m), 520 (s) cm−1.

1,3-Di(benz­yloxy)-2-methyl­sulfanylimidazolium tetra­fluor­ido­borate (2): Tri­methyl­oxonium tetra­fluorido­borate (0.26 g, 1.7 mmol) was added to a solution of 1,3-di(benz­yloxy)imidazoline-2-thione (0.51 g, 1.6 mmol) in CH2Cl2 (8 ml) in a Teflon test tube under argon. The mixture was stirred for 3 d at room temperature, then the solvent was evaporated. The residue was dissolved in MeOH (15 ml), precipitated with Et2O (15 ml), filtered, washed with Et2O and dried to yield a colourless powder. Single crystals were obtained by slow evaporation from an MeOH solution: Yield 0.42 g (62%), m.p. 407 K. 1H NMR (300 MHz, DMSO-d6): δ 2.54 (s, 3H), 5.45 (s, 4H), 7.49 (s, 10H), 8.36 (s, 2H) ppm 13C NMR (75 MHz, DMSO-d6): δ 16.4, 83.1 (2C), 118.9 (2C), 128.9 (4C), 130.2 (2C), 130.4 (4C), 131.8 (2C), 136.8 ppm IR (neat): ν 3167 (w), 3137 (w), 1550 (w), 1492 (w), 1457 (w), 1384 (w), 1354 (w), 1214 (w), 1057 (vs), 1039 (vs), 907 (m), 873 (m), 844 (m), 773 (s), 739 (s), 699 (s), 671 (s), 575 (m), 499 (m) cm−1.

6. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 3[link]. All hydrogen atoms were identified in difference maps. Methyl H atoms were idealized and included as rigid groups allowed to rotate but not tip (C—H = 0.98 Å), and their Uiso parameters were set to 1.5 Ueq(C) of the parent carbon atom. H atoms bonded to secondary carbon atoms (C—H = 0.99 Å), and H atoms bonded to C atoms in aromatic rings (C—H = 0.95 Å) were positioned geometrically and refined with Uiso set to 1.2 Ueq(C) of the parent carbon atom.

Table 3
Experimental details

  1 2
Crystal data
Chemical formula C6H11N2O2S+·BF4− C18H19N2O2S+·BF4−
Mr 262.04 414.22
Crystal system, space group Monoclinic, P21/n Orthorhombic, Pc21b
Temperature (K) 173 173
a, b, c (Å) 8.1049 (7), 11.6979 (10), 12.0810 (12) 7.9117 (3), 11.4760 (4), 20.9659 (7)
α, β, γ (°) 90, 90.069 (9), 90 90, 90, 90
V (Å3) 1145.40 (18) 1903.59 (12)
Z 4 4
Radiation type Mo Kα Mo Kα
μ (mm−1) 0.32 0.22
Crystal size (mm) 0.20 × 0.14 × 0.12 0.44 × 0.36 × 0.12
 
Data collection
Diffractometer Rigaku Oxford Diffraction Xcalibur, Ruby, Gemini ultra Rigaku Oxford Diffraction Xcalibur, Ruby, Gemini ultra
Absorption correction Multi-scan (CrysAlis PRO; Rigaku OD, 2015[Rigaku OD (2015). CrysAlis PRO. Rigaku Oxford Diffraction, Yarnton, England.]) Multi-scan (CrysAlis PRO; Rigaku OD, 2015[Rigaku OD (2015). CrysAlis PRO. Rigaku Oxford Diffraction, Yarnton, England.])
Tmin, Tmax 0.973, 1 0.936, 1
No. of measured, independent and observed [I > 2σ(I)] reflections 8186, 2175, 1640 11654, 3555, 3293
Rint 0.041 0.029
(sin θ/λ)max (Å−1) 0.610 0.610
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.037, 0.088, 1.04 0.030, 0.067, 1.06
No. of reflections 2175 3555
No. of parameters 148 311
No. of restraints 0 368
H-atom treatment H-atom parameters constrained H-atom parameters constrained
Δρmax, Δρmin (e Å−3) 0.25, −0.26 0.18, −0.23
Absolute structure – Flack x determined using 1454 quotients [(I+)−(I−)]/[(I+)+(I−)] (Parsons et al., 2013[Parsons, S., Flack, H. D. & Wagner, T. (2013). Acta Cryst. B69, 249-259.]).
Absolute structure parameter – 0.02 (3)
Computer programs: CrysAlis PRO (Rigaku OD, 2015[Rigaku OD (2015). CrysAlis PRO. Rigaku Oxford Diffraction, Yarnton, England.]), SIR2002 (Burla et al., 2003[Burla, M. C., Camalli, M., Carrozzini, B., Cascarano, G. L., Giacovazzo, C., Polidori, G. & Spagna, R. (2003). J. Appl. Cryst. 36, 1103.]), SHELXL2014/6 (Sheldrick, 2015[Sheldrick, G. M. (2015). Acta Cryst. C71, 3-8.]), XP/SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]), Mercury (Macrae et al., 2020[Macrae, C. F., Sovago, I., Cottrell, S. J., Galek, P. T. A., McCabe, P., Pidcock, E., Platings, M., Shields, G. P., Stevens, J. S., Towler, M. & Wood, P. A. (2020). J. Appl. Cryst. 53, 226-235.]) and publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

The structure of 2 displays disorder of the tetra­fluorido­borate ion involving three distinct components. Therefore, distance restraints were applied for all chemically equivalent B—F and F⋯F distances and restraints on displacement parameters of the F atoms affected by disorder were applied.

Supporting information

CCDC references: 1989707; 1989706

Crystal structure: contains datablocks 1, 2, global. DOI: https://doi.org/10.1107/S2056989020003643/wm5549sup1.cif

Structure factors: contains datablock 1. DOI: https://doi.org/10.1107/S2056989020003643/wm55491sup2.hkl

Structure factors: contains datablock 2. DOI: https://doi.org/10.1107/S2056989020003643/wm55492sup3.hkl

Supporting information file. DOI: https://doi.org/10.1107/S2056989020003643/wm55491sup4.cml

checkCIF report


Computing details top

For both structures, data collection: CrysAlis PRO (Rigaku OD, 2015); cell refinement: CrysAlis PRO (Rigaku OD, 2015); data reduction: CrysAlis PRO (Rigaku OD, 2015); program(s) used to solve structure: SIR2002 (Burla et al., 2003); program(s) used to refine structure: SHELXL2014/6 (Sheldrick, 2015); molecular graphics: XP/SHELXTL (Sheldrick, 2008) and Mercury (Macrae et al., 2020); software used to prepare material for publication: publCIF (Westrip, 2010).

1,3-Dimethoxy-2-(methylsulfanyl)imidazolium tetrafluoridoborate (1) top
Crystal data top
C6H11N2O2S+·BF4−F(000) = 536
Mr = 262.04Dx = 1.520 Mg m−3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
a = 8.1049 (7) ÅCell parameters from 1882 reflections
b = 11.6979 (10) Åθ = 4.5–23.4°
c = 12.0810 (12) ŵ = 0.32 mm−1
β = 90.069 (9)°T = 173 K
V = 1145.40 (18) Å3Block, colourless
Z = 40.20 × 0.14 × 0.12 mm
Data collection top
Rigaku Oxford Diffraction Xcalibur, Ruby, Gemini ultra
diffractometer		2175 independent reflections
Radiation source: fine-focus sealed X-ray tube, Enhance (Mo) X-ray Source1640 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.041
Detector resolution: 10.3575 pixels mm-1θmax = 25.7°, θmin = 3.4°
ω scansh = −9→9
Absorption correction: multi-scan
(CrysAlisPro; Rigaku OD, 2015)		k = −14→14
Tmin = 0.973, Tmax = 1l = −11→14
8186 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.037Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.088H-atom parameters constrained
S = 1.04 w = 1/[σ2(Fo2) + (0.0305P)2 + 0.4296P]
where P = (Fo2 + 2Fc2)/3
2175 reflections(Δ/σ)max < 0.001
148 parametersΔρmax = 0.25 e Å−3
0 restraintsΔρmin = −0.26 e Å−3
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
S10.41330 (7)0.47008 (5)0.72979 (5)0.03744 (19)
F10.08382 (16)0.25059 (12)0.80034 (13)0.0477 (4)
F2−0.01740 (16)0.36253 (12)0.66193 (10)0.0439 (4)
F3−0.0285 (2)0.42160 (11)0.83926 (11)0.0516 (4)
F4−0.18980 (16)0.27590 (12)0.78296 (13)0.0514 (4)
O10.46146 (18)0.22793 (13)0.61505 (12)0.0344 (4)
O20.45275 (18)0.38275 (13)0.97279 (12)0.0340 (4)
N20.4484 (2)0.30437 (14)0.88842 (14)0.0255 (4)
N10.4543 (2)0.23500 (14)0.72783 (14)0.0251 (4)
C10.4420 (2)0.33444 (17)0.78163 (17)0.0246 (5)
C20.4692 (2)0.14498 (18)0.79882 (19)0.0304 (5)
H20.48100.06670.77960.036*
C30.4638 (2)0.18919 (18)0.90157 (19)0.0301 (5)
H30.46960.14840.96950.036*
C50.2956 (3)0.3860 (2)1.0302 (2)0.0389 (6)
H5A0.20670.39880.97660.058*
H5B0.29650.44821.08450.058*
H5C0.27750.31311.06830.058*
C60.6002 (3)0.4910 (2)0.6533 (2)0.0477 (7)
H6A0.69510.48230.70290.072*
H6B0.60070.56800.62130.072*
H6C0.60690.43430.59380.072*
B1−0.0377 (3)0.3266 (2)0.7711 (2)0.0276 (6)
C40.3017 (3)0.1968 (2)0.5703 (2)0.0471 (7)
H4A0.26810.12260.60040.071*
H4B0.30880.19170.48950.071*
H4C0.22030.25490.59080.071*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
S10.0346 (3)0.0294 (3)0.0484 (4)0.0073 (2)0.0086 (3)0.0077 (3)
F10.0337 (8)0.0490 (9)0.0605 (10)0.0094 (6)−0.0015 (7)0.0051 (7)
F20.0500 (8)0.0562 (9)0.0254 (7)0.0007 (7)0.0062 (6)0.0000 (6)
F30.0889 (12)0.0336 (8)0.0323 (8)−0.0033 (7)0.0035 (7)−0.0043 (6)
F40.0278 (7)0.0643 (10)0.0621 (10)−0.0099 (7)−0.0001 (7)0.0120 (8)
O10.0272 (8)0.0512 (10)0.0247 (9)−0.0011 (7)0.0056 (6)−0.0087 (7)
O20.0307 (8)0.0409 (9)0.0305 (9)−0.0101 (7)0.0022 (7)−0.0140 (7)
N20.0237 (9)0.0262 (9)0.0266 (10)−0.0035 (7)−0.0003 (7)−0.0059 (8)
N10.0219 (9)0.0292 (10)0.0242 (10)−0.0009 (7)0.0008 (7)−0.0048 (8)
C10.0183 (10)0.0277 (11)0.0276 (12)0.0007 (9)0.0019 (9)−0.0019 (10)
C20.0243 (11)0.0254 (11)0.0415 (14)−0.0001 (9)−0.0022 (10)0.0010 (10)
C30.0277 (11)0.0289 (12)0.0337 (14)−0.0020 (9)−0.0052 (10)0.0052 (10)
C50.0343 (13)0.0493 (15)0.0331 (13)0.0004 (11)0.0069 (10)−0.0069 (11)
C60.0413 (15)0.0406 (14)0.0613 (18)0.0012 (12)0.0150 (13)0.0150 (13)
B10.0253 (13)0.0294 (13)0.0282 (14)−0.0015 (11)0.0014 (10)−0.0017 (11)
C40.0339 (13)0.0779 (19)0.0294 (14)−0.0056 (13)−0.0041 (11)−0.0124 (13)
Geometric parameters (Å, º) top
S1—C11.722 (2)N1—C21.363 (3)
S1—C61.792 (2)C2—C31.346 (3)
F1—B11.373 (3)C2—H20.9500
F2—B11.394 (3)C3—H30.9500
F3—B11.385 (3)C5—H5A0.9800
F4—B11.376 (3)C5—H5B0.9800
O1—N11.366 (2)C5—H5C0.9800
O1—C41.449 (3)C6—H6A0.9800
O2—N21.372 (2)C6—H6B0.9800
O2—C51.451 (3)C6—H6C0.9800
N2—C11.338 (3)C4—H4A0.9800
N2—C31.362 (3)C4—H4B0.9800
N1—C11.336 (3)C4—H4C0.9800
C1—S1—C6101.52 (10)O2—C5—H5C109.5
N1—O1—C4110.37 (15)H5A—C5—H5C109.5
N2—O2—C5110.52 (15)H5B—C5—H5C109.5
C1—N2—C3112.08 (17)S1—C6—H6A109.5
C1—N2—O2122.80 (17)S1—C6—H6B109.5
C3—N2—O2124.90 (17)H6A—C6—H6B109.5
C1—N1—C2111.90 (18)S1—C6—H6C109.5
C1—N1—O1122.75 (17)H6A—C6—H6C109.5
C2—N1—O1125.22 (17)H6B—C6—H6C109.5
N1—C1—N2103.73 (17)F1—B1—F4109.66 (19)
N1—C1—S1129.46 (17)F1—B1—F3109.20 (19)
N2—C1—S1126.73 (16)F4—B1—F3109.36 (18)
C3—C2—N1106.29 (19)F1—B1—F2110.68 (18)
C3—C2—H2126.9F4—B1—F2109.58 (19)
N1—C2—H2126.9F3—B1—F2108.32 (18)
C2—C3—N2106.00 (19)O1—C4—H4A109.5
C2—C3—H3127.0O1—C4—H4B109.5
N2—C3—H3127.0H4A—C4—H4B109.5
O2—C5—H5A109.5O1—C4—H4C109.5
O2—C5—H5B109.5H4A—C4—H4C109.5
H5A—C5—H5B109.5H4B—C4—H4C109.5
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C2—H2···F3i0.952.263.137 (3)154
C2—H2···F2i0.952.513.361 (3)150
C3—H3···F2ii0.952.333.207 (3)153
C4—H4B···F3iii0.982.613.408 (3)139
C4—H4B···F4iii0.982.523.487 (3)168
C4—H4C···F20.982.463.418 (3)167
C5—H5A···F30.982.543.519 (3)177
Symmetry codes: (i) −x+1/2, y−1/2, −z+3/2; (ii) x+1/2, −y+1/2, z+1/2; (iii) x+1/2, −y+1/2, z−1/2.
1,3-Dibenzyloxy-2-(methylsulfanyl)imidazolium tetrafluoridoborate (2) top
Crystal data top
C18H19N2O2S+·BF4−F(000) = 856
Mr = 414.22Dx = 1.445 Mg m−3
Orthorhombic, Pc21bMo Kα radiation, λ = 0.71073 Å
Hall symbol: P -2bc -2cCell parameters from 6176 reflections
a = 7.9117 (3) Åθ = 3.1–28.6°
b = 11.4760 (4) ŵ = 0.22 mm−1
c = 20.9659 (7) ÅT = 173 K
V = 1903.59 (12) Å3Plate, colourless
Z = 40.44 × 0.36 × 0.12 mm
Data collection top
Rigaku Oxford Diffraction Xcalibur, Ruby, Gemini ultra
diffractometer		3555 independent reflections
Graphite monochromator3293 reflections with I > 2σ(I)
Detector resolution: 10.3575 pixels mm-1Rint = 0.029
ω scansθmax = 25.7°, θmin = 3.2°
Absorption correction: multi-scan
(CrysAlisPro; Rigaku OD, 2015)		h = −9→8
Tmin = 0.936, Tmax = 1k = −13→13
11654 measured reflectionsl = −19→25
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)] = 0.030H-atom parameters constrained
wR(F2) = 0.067 w = 1/[σ2(Fo2) + (0.031P)2 + 0.3041P]
where P = (Fo2 + 2Fc2)/3
S = 1.06(Δ/σ)max = 0.007
3555 reflectionsΔρmax = 0.18 e Å−3
311 parametersΔρmin = −0.22 e Å−3
368 restraintsAbsolute structure: Flack x determined using 1454 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons et al., 2013).
Primary atom site location: structure-invariant direct methodsAbsolute structure parameter: 0.02 (3)
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*/UeqOcc. (<1)
B10.7773 (4)0.7700 (3)0.47458 (15)0.0309 (7)
F10.6678 (2)0.84120 (18)0.44219 (10)0.0588 (6)
F2B0.719 (2)0.7454 (15)0.5332 (6)0.071 (6)0.341 (5)
F3B0.781 (3)0.6596 (8)0.4439 (7)0.072 (5)0.341 (5)
F4B0.9356 (13)0.8091 (14)0.4735 (12)0.083 (9)0.341 (5)
F2C0.7136 (18)0.6688 (14)0.4845 (18)0.093 (7)0.238 (4)
F3C0.9288 (16)0.7723 (19)0.4449 (8)0.060 (6)0.238 (4)
F4C0.803 (3)0.834 (2)0.5316 (6)0.089 (6)0.238 (4)
F2A0.6947 (13)0.7094 (11)0.5212 (5)0.044 (3)0.421 (4)
F3A0.849 (2)0.6901 (17)0.4354 (6)0.126 (8)0.421 (4)
F4A0.9031 (14)0.8315 (12)0.5042 (8)0.076 (5)0.421 (4)
S10.33131 (8)0.61824 (6)0.53046 (3)0.02961 (17)
O20.3430 (2)0.66702 (16)0.38403 (8)0.0283 (4)
O10.2637 (2)0.87919 (17)0.57345 (8)0.0273 (4)
N10.2835 (2)0.85434 (19)0.50947 (9)0.0223 (5)
N20.3093 (2)0.75797 (18)0.42440 (10)0.0214 (5)
C10.3058 (3)0.7453 (2)0.48800 (12)0.0208 (5)
C30.2924 (3)0.8725 (2)0.40683 (12)0.0256 (6)
H30.29370.90280.36470.031*
C120.1490 (3)0.6677 (2)0.29313 (12)0.0261 (6)
C90.2992 (3)1.0534 (3)0.75895 (14)0.0350 (7)
H90.24911.12180.77620.042*
C100.3228 (3)1.0439 (3)0.69382 (13)0.0304 (6)
H100.28931.10570.66650.036*
C50.3952 (3)0.9444 (2)0.66841 (12)0.0280 (6)
C60.4421 (4)0.8550 (3)0.70894 (13)0.0342 (7)
H60.49070.78600.69190.041*
C110.1862 (3)0.6160 (3)0.35716 (12)0.0314 (6)
H11A0.09040.63120.38640.038*
H11B0.19950.53050.35300.038*
C150.0978 (4)0.7695 (3)0.17451 (14)0.0389 (7)
H150.08110.80470.13400.047*
C170.0445 (3)0.7640 (3)0.28694 (13)0.0331 (6)
H17−0.01030.79530.32340.040*
C20.2736 (3)0.9333 (2)0.46104 (12)0.0252 (6)
H20.25671.01500.46490.030*
C70.4189 (4)0.8652 (3)0.77389 (14)0.0392 (7)
H70.45210.80340.80130.047*
C80.3482 (4)0.9641 (3)0.79913 (14)0.0369 (7)
H80.33290.97120.84390.044*
C40.4199 (4)0.9319 (3)0.59824 (13)0.0405 (8)
H4A0.43961.00900.57830.049*
H4B0.51830.88120.58910.049*
C130.2265 (3)0.6217 (3)0.23927 (12)0.0318 (6)
H130.29760.55540.24290.038*
C180.1150 (4)0.5878 (3)0.55032 (17)0.0498 (9)
H18A0.06660.65450.57310.075*
H18B0.10980.51850.57750.075*
H18C0.05060.57380.51110.075*
C140.2001 (4)0.6726 (3)0.18030 (14)0.0396 (7)
H140.25270.64060.14350.047*
C160.0199 (4)0.8148 (3)0.22780 (14)0.0389 (7)
H16−0.05110.88120.22390.047*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
B10.0229 (16)0.040 (2)0.0298 (17)0.0004 (14)−0.0001 (12)0.0065 (16)
F10.0409 (11)0.0542 (13)0.0813 (14)−0.0050 (9)−0.0231 (9)0.0296 (11)
F2B0.102 (13)0.081 (13)0.029 (4)0.002 (9)0.017 (5)−0.004 (6)
F3B0.136 (16)0.027 (4)0.052 (7)−0.007 (7)−0.004 (8)−0.014 (4)
F4B0.025 (4)0.051 (9)0.17 (3)0.002 (4)0.011 (10)0.043 (14)
F2C0.066 (9)0.037 (10)0.17 (2)−0.010 (7)−0.002 (14)0.053 (14)
F3C0.031 (7)0.087 (16)0.061 (8)0.015 (7)0.020 (5)−0.001 (8)
F4C0.092 (12)0.138 (17)0.037 (6)0.040 (11)−0.013 (7)−0.024 (8)
F2A0.039 (3)0.038 (6)0.055 (7)−0.012 (4)0.007 (4)0.014 (5)
F3A0.101 (10)0.21 (2)0.071 (6)0.089 (12)0.018 (7)−0.037 (11)
F4A0.044 (7)0.073 (8)0.110 (11)−0.038 (7)−0.047 (7)0.047 (7)
S10.0245 (3)0.0282 (3)0.0362 (4)0.0029 (3)0.0005 (2)0.0108 (3)
O20.0270 (9)0.0310 (10)0.0269 (9)0.0062 (8)−0.0021 (7)−0.0098 (8)
O10.0244 (9)0.0357 (11)0.0217 (9)−0.0087 (8)0.0059 (6)−0.0073 (8)
N10.0218 (10)0.0238 (12)0.0211 (11)−0.0014 (9)0.0033 (8)−0.0032 (9)
N20.0207 (10)0.0211 (12)0.0225 (11)0.0024 (9)0.0010 (8)−0.0032 (9)
C10.0180 (11)0.0229 (14)0.0214 (13)−0.0012 (10)0.0001 (9)0.0016 (11)
C30.0226 (12)0.0271 (14)0.0271 (13)−0.0004 (11)0.0009 (9)0.0071 (13)
C120.0228 (12)0.0268 (14)0.0285 (13)−0.0044 (11)−0.0056 (10)−0.0050 (12)
C90.0378 (15)0.0281 (16)0.0390 (16)0.0001 (12)0.0049 (12)−0.0099 (14)
C100.0317 (14)0.0248 (15)0.0345 (15)−0.0033 (12)−0.0019 (11)0.0027 (13)
C50.0228 (13)0.0330 (15)0.0281 (14)−0.0099 (11)0.0013 (10)−0.0051 (12)
C60.0286 (14)0.0287 (16)0.0454 (17)0.0007 (12)−0.0035 (11)−0.0099 (14)
C110.0370 (14)0.0239 (13)0.0332 (14)−0.0047 (13)−0.0049 (10)−0.0033 (15)
C150.0431 (17)0.0391 (18)0.0345 (16)−0.0097 (14)−0.0149 (13)0.0054 (14)
C170.0259 (13)0.0358 (17)0.0376 (16)0.0009 (12)−0.0036 (11)−0.0079 (14)
C20.0213 (13)0.0197 (13)0.0346 (15)−0.0018 (10)0.0032 (10)0.0007 (12)
C70.0406 (17)0.0327 (17)0.0443 (17)−0.0056 (13)−0.0148 (12)0.0075 (16)
C80.0434 (18)0.0428 (18)0.0244 (15)−0.0114 (14)−0.0016 (12)−0.0032 (13)
C40.0281 (14)0.061 (2)0.0327 (15)−0.0200 (14)0.0055 (12)−0.0142 (15)
C130.0338 (14)0.0274 (14)0.0341 (15)0.0017 (13)−0.0056 (10)−0.0108 (15)
C180.0327 (16)0.042 (2)0.074 (2)0.0042 (14)0.0209 (15)0.0267 (17)
C140.0437 (17)0.0448 (18)0.0302 (15)−0.0041 (15)−0.0035 (13)−0.0108 (14)
C160.0351 (16)0.0323 (17)0.049 (2)0.0020 (13)−0.0142 (13)0.0023 (14)
Geometric parameters (Å, º) top
B1—F2C1.283 (11)C9—H90.9500
B1—F4B1.330 (10)C10—C51.384 (4)
B1—F2B1.342 (11)C10—H100.9500
B1—F3C1.350 (11)C5—C61.383 (4)
B1—F3A1.355 (10)C5—C41.491 (4)
B1—F2A1.367 (8)C6—C71.379 (4)
B1—F4A1.369 (9)C6—H60.9500
B1—F11.371 (4)C11—H11A0.9900
B1—F4C1.414 (12)C11—H11B0.9900
B1—F3B1.422 (9)C15—C161.378 (4)
S1—C11.721 (3)C15—C141.381 (5)
S1—C181.795 (3)C15—H150.9500
O2—N21.370 (3)C17—C161.384 (4)
O2—C111.483 (3)C17—H170.9500
O1—N11.380 (3)C2—H20.9500
O1—C41.471 (3)C7—C81.372 (5)
N1—C11.341 (3)C7—H70.9500
N1—C21.363 (3)C8—H80.9500
N2—C11.342 (3)C4—H4A0.9900
N2—C31.372 (3)C4—H4B0.9900
C3—C21.342 (4)C13—C141.383 (4)
C3—H30.9500C13—H130.9500
C12—C171.386 (4)C18—H18A0.9800
C12—C131.389 (4)C18—H18B0.9800
C12—C111.497 (4)C18—H18C0.9800
C9—C81.382 (4)C14—H140.9500
C9—C101.383 (4)C16—H160.9500
F4B—B1—F2B114.1 (10)C7—C6—C5120.6 (3)
F2C—B1—F3C116.1 (11)C7—C6—H6119.7
F3A—B1—F2A106.7 (8)C5—C6—H6119.7
F3A—B1—F4A108.8 (8)O2—C11—C12110.4 (2)
F2A—B1—F4A106.6 (7)O2—C11—H11A109.6
F2C—B1—F1111.8 (7)C12—C11—H11A109.6
F4B—B1—F1112.7 (7)O2—C11—H11B109.6
F2B—B1—F1111.3 (8)C12—C11—H11B109.6
F3C—B1—F1108.8 (8)H11A—C11—H11B108.1
F3A—B1—F1111.5 (6)C16—C15—C14119.7 (3)
F2A—B1—F1110.8 (5)C16—C15—H15120.2
F4A—B1—F1112.2 (6)C14—C15—H15120.2
F2C—B1—F4C112.7 (11)C16—C17—C12120.3 (3)
F3C—B1—F4C104.6 (10)C16—C17—H17119.9
F1—B1—F4C101.7 (6)C12—C17—H17119.9
F4B—B1—F3B105.9 (8)C3—C2—N1106.2 (2)
F2B—B1—F3B103.5 (8)C3—C2—H2126.9
F1—B1—F3B108.6 (7)N1—C2—H2126.9
C1—S1—C1899.97 (13)C8—C7—C6120.3 (3)
N2—O2—C11111.87 (18)C8—C7—H7119.8
N1—O1—C4109.43 (17)C6—C7—H7119.8
C1—N1—C2112.2 (2)C7—C8—C9119.5 (3)
C1—N1—O1122.3 (2)C7—C8—H8120.2
C2—N1—O1125.5 (2)C9—C8—H8120.2
C1—N2—O2122.4 (2)O1—C4—C5106.1 (2)
C1—N2—C3111.6 (2)O1—C4—H4A110.5
O2—N2—C3125.7 (2)C5—C4—H4A110.5
N1—C1—N2103.6 (2)O1—C4—H4B110.5
N1—C1—S1129.23 (19)C5—C4—H4B110.5
N2—C1—S1127.1 (2)H4A—C4—H4B108.7
C2—C3—N2106.4 (2)C14—C13—C12120.0 (3)
C2—C3—H3126.8C14—C13—H13120.0
N2—C3—H3126.8C12—C13—H13120.0
C17—C12—C13119.3 (3)S1—C18—H18A109.5
C17—C12—C11121.2 (2)S1—C18—H18B109.5
C13—C12—C11119.4 (2)H18A—C18—H18B109.5
C8—C9—C10120.4 (3)S1—C18—H18C109.5
C8—C9—H9119.8H18A—C18—H18C109.5
C10—C9—H9119.8H18B—C18—H18C109.5
C9—C10—C5120.1 (3)C15—C14—C13120.5 (3)
C9—C10—H10120.0C15—C14—H14119.8
C5—C10—H10120.0C13—C14—H14119.8
C6—C5—C10119.1 (2)C15—C16—C17120.3 (3)
C6—C5—C4120.0 (3)C15—C16—H16119.9
C10—C5—C4120.9 (3)C17—C16—H16119.9
N1—O1—C4—C5−174.2 (2)N2—O2—C11—C1295.5 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C2—H2···F2Ai0.952.283.200 (13)162
C2—H2···F3Bi0.952.553.302 (14)136
C2—H2···F2Ci0.952.072.936 (10)150
C4—H4B···F2B0.992.523.472 (17)162
C4—H4A···F3Bi0.992.503.183 (13)126
C4—H4A···F2Ci0.992.563.39 (3)141
C4—H4B···F4C0.992.613.522 (19)153
C8—H8···F1ii0.952.543.317 (4)139
C10—H10···F3Bi0.952.463.282 (12)145
C11—H11A···F3Aiii0.992.273.247 (13)167
C11—H11A···F3Ciii0.992.403.279 (15)148
C18—H18C···F3Aiii0.982.623.409 (14)138
Symmetry codes: (i) −x+1, y+1/2, −z+1; (ii) −x+1, y, z+1/2; (iii) x−1, y, z.
 

Footnotes

‡Deceased.

References

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ISSN: 2056-9890
Volume 76| Part 4| April 2020| Pages 552-556
https://doi.org/10.1107/S2056989020003643
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