The asymmetric units for the salts 4-(4-fluoro-phen-yl)-1-isopropyl-1,2,4-triazol-1-ium iodide, C11H13FN3 (+)·I(-), (1), 1-isopropyl-4-(4-methyl-phen-yl)-1,2,4-triazol-1-ium iodide, C12H16N3 (+)·I(-), (2), 1-isopropyl-4-phenyl-1,2,4-triazol-1-ium iodide, C11H14N3 (+)·I(-), (3), and 1-methyl-4-phenyl-1,2,4-triazol-1-ium iodide, C9H10N3 (+)·I(-), (4), contain one cation and one iodide ion, whereas in 1-benzyl-4-phenyl-1,2,4-triazol-1-ium bromide monohydrate, C15H14N3 (+)·Br(-)·H2O, (5), there is an additional single water mol-ecule. There is a predominant C-H⋯X(halide) inter-action for all salts, resulting in a two-dimensional extended sheet network between the triazolium cation and the halide ions. For salts with para-substitution on the aryl ring, there is an additional π-anion inter-action between a triazolium carbon and iodide displayed by the layers. For salts without the para-substitution on the aryl ring, the π-π inter-actions are between the triazolium and aryl rings. The melting points of these salts agree with the predicted substituent inductive effects.
The asymmetric units for the salts 4-(4-fluoro-phen-yl)-1-isopropyl-1,2,4-triazol-1-ium iodide, C11H13FN3 (+)·I(-), (1), 1-isopropyl-4-(4-methyl-phen-yl)-1,2,4-triazol-1-ium iodide, C12H16N3 (+)·I(-), (2), 1-isopropyl-4-phenyl-1,2,4-triazol-1-ium iodide, C11H14N3 (+)·I(-), (3), and 1-methyl-4-phenyl-1,2,4-triazol-1-ium iodide, C9H10N3 (+)·I(-), (4), contain one cation and one iodide ion, whereas in 1-benzyl-4-phenyl-1,2,4-triazol-1-ium bromide monohydrate, C15H14N3 (+)·Br(-)·H2O, (5), there is an additional single water mol-ecule. There is a predominant C-H⋯X(halide) inter-action for all salts, resulting in a two-dimensional extended sheet network between the triazolium cation and the halide ions. For salts with para-substitution on the aryl ring, there is an additional π-anion inter-action between a triazolium carbon and iodide displayed by the layers. For salts without the para-substitution on the aryl ring, the π-π inter-actions are between the triazolium and aryl rings. The melting points of these salts agree with the predicted substituent inductive effects.
Literature syntheses of asymmetric1,2,4-triazoliumcations have increased in recent years due to their utility as cations in ionic liquids (ILs) and as precursors to N-heterocycliccarbenes (NHCs) (Dwivedi et al., 2014 ▸; Meyer & Strassner, 2011 ▸; Mochida et al., 2011 ▸; Nelson, 2015 ▸; Porcar et al., 2013 ▸; Strassner et al., 2013 ▸). Most structural analyses of these cations have been performed to understand how the intermolecular features of ILs affect their physical properties. (Porcar et al., 2013 ▸).Most recently, Strassner has introduced a new group of ionic liquids called ‘TAAILs’ (tunable aryl–alkyl ionic liquids) (Ahrens et al., 2009 ▸). The idea is to tune the properties of the ionic liquids through modification of the aryl and alkyl substituents of an imidazolecation (Scheme 1). The new cations can still be combined with the previously used anions in ILs. These workers have demonstrated that electron-donating para-substituents on the aryl group lower the melting point, while electron-withdrawing para-substituents raise the melting point. Thus one can tune the IL properties through the introduction of an electronic variation through para-substitution on the aryl rings. This group has also extended the concept to the 1,2,4-triazoliumcation core (Meyer & Strassner, 2011 ▸).Our group became interested in learning how the aryl/alkyl substituents on the triazole ring affect the solid-state structures of the salts because strategicchoice of substituents should allow tailorable π–π interactions as predicted by Strassner’s group (Meyer & Strassner, 2011 ▸). Herein, the preparation and crystal structure analyses of salts (1)–(5) are discussed (Scheme 2). Cations (1)–(3) compare the inductive effects of the electronic para-substituents in the aryl group, while cations (3)–(5) contrast the steric bulk of the alkyl substituents. None of the compounds presented here are ILs because we used iodide or bromidecounter-anions to facilitate crystal formation. Understanding interactions in the solid state may help better design systems where the triazolium cations are needed.
Structural commentary
Salts (1) and (2) crystallized in the orthorhombic space group Pccn, salt (3) in the monoclinic space group P21
/n, and salt (5) in the monoclinic space group C2/c. Salt (4) crystallized in the non-centrosymmetric space group Cc with a Flack parameter of −0.01 (2) indicating the absolute structure is well determined.The asymmetric unit for all saltscontains one cation and one iodide or bromide ion, except for salt (5), where there is an additional single water molecule. The bond lengths in the triazolium rings for all salts indicate aromaticity with C—N and N—N bond distances in the narrow range of 1.292 (6)–1.365 (5) Å for (1), 1.304 (5)–1.365 (4) Å for (2), 1.301 (3)–1.374 (3) Å for (3), 1.297 (6)–1.370 (5) Å for (4), and 1.299 (4)–1.375 (4) Å for (5); with N—C—N bond angles of 107.7 (4)° for (1), 107.5 (3)° for (2), 107.3 (2)° for (3), 107.5 (3)° for (4), and 107.2 (2)° for (5). These values are very similar to those reported for 4-phenyl-1-ethyl-4H-1,2,4-triazolium bromide, in which the C—N and N—N bond distances range is 1.301 (3)–1.469 (4) Å and the N—C—N bond angle is 107.8 (2)° (Meyer & Strassner, 2011 ▸). The phenyl ring for these salts lies in almost the same plane as the triazole ring with torsion angles of 6.5 (7)° for (1), 24.1 (5)° for (2), 12.9 (4)° for (4), and 3.1 (4)° for (5); except for salt (3) where the phenyl ring is almost perpendicular to the triazole ring with a torsion angle of 65.1 (3)°. The torsion angle between the phenyl and triazole rings for the reported triazolium bromide is 5.8 (4)° (Meyer & Strassner, 2011 ▸). There are no significant intramolecular interactions found in any of the salts.
Supramolecular features
For all five salts, there is a predominant C—H⋯halide intermolecular interaction between the hydrogen atoms in the triazolium ring and the counter ions, forming an extended network (Figs. 1–5 ▸
▸
▸
▸
▸ and Tables 1 ▸–5 ▸
▸
▸
▸). For the asymmetric unit in salt (1), there are a total of four C—H⋯I− intermolecular interactions with two neighboring molecules (Fig. 1 ▸, Table 1 ▸). Each iodide ion interacts with two C—H moieties from the triazolium ring and two from the ortho C—H moieties of the aryl group. There is an additional C—H⋯N interaction between the meta C—H of the aryl ring and the triazolium nitrogen atom. The fluorine substituent in the para- position of the aryl ring is not an acceptor in any of the C—H interactions in salt (1). The asymmetric unit of salt (2) shows a total of three C—H⋯I− intermolecular interactions with two neighboring molecules (Fig. 2 ▸, Table 2 ▸). Two C—H moieties from the triazolium ring and one ortho C—H of the aryl ring interact with one iodide ion. In the asymmetric unit of salt (3) (Fig. 3 ▸, Table 3 ▸), there are a total of three C—H⋯I− intermolecular interactions, two from the triazolium C—H moieties, and one methinehydrogen atom from the isopropyl group because the aryl ring does not lie on the plane of the triazolium ring. For salts (4) and (5) (Figs. 4 ▸ and 5 ▸, Tables 4 ▸ and 5 ▸), there are only a total of two C—H⋯I/Br− intermolecular interactions, both from the triazole ring’s C—H groups. However, in salt (5), a water molecule is in the asymmetric unit along the plane of the triazole and phenyl rings and is also interacting with the Br− ion and the ortho C—H of the phenyl ring. A square-shaped hydrogen-bonding network is formed between two bromide ions and water molecules (Fig. 6 ▸ and Table 5 ▸). Thus, each bromide ion has two acceptor interactions with waterhydrogen atoms and one acceptor interaction with the C—H of the triazolium ring, and each water molecule has two donor interactions with the bromide ions and one acceptor interaction with the ortho C—H of the aryl ring (Figs. 5 ▸ and 6 ▸, Table 5 ▸).
Figure 1
Extended sheet network viewed along the c axis of salt (1). H atoms not participating in the extended sheet network are not shown. For symmetry codes, see Table 1 ▸.
Figure 2
Extended sheet network viewed along the c axis of salt (2). H atoms not participating in the extended sheet network are not shown. For symmetry codes, see Table 2 ▸.
Figure 3
Extended sheet network viewed along the c axis of salt (3). H atoms not participating in the extended sheet network are not shown. For symmetry codes, see Table 3 ▸.
Figure 4
Extended sheet network viewed along the a axis of salt (4). H atoms not participating in the extended sheet network are not shown. For symmetry codes, see Table 4 ▸.
Figure 5
Extended sheet network of salt (5). H atoms not participating in the extended sheet network are not shown. For symmetry codes, see Table 5 ▸.
Table 1
Hydrogen-bond geometry (Å, °) for salt (1)
D—H⋯A
D—H
H⋯A
D⋯A
D—H⋯A
C1—H1⋯I1i
0.95
2.97
3.912 (4)
170
C2—H2⋯I1ii
0.95
2.83
3.774 (5)
173
C7—H7⋯I1i
0.95
2.86
3.801 (4)
170
C8—H8⋯N3iii
0.95
2.60
3.548 (6)
174
C11—H11⋯I1ii
0.95
3.13
4.083 (5)
177
Symmetry codes: (i) ; (ii) ; (iii) .
Table 2
Hydrogen-bond geometry (Å, °) for salt (2)
D—H⋯A
D—H
H⋯A
D⋯A
D—H⋯A
C1—H1⋯I1i
0.95
3.06
3.901 (3)
149
C2—H2⋯I1ii
0.95
2.84
3.771 (4)
168
C3—H3⋯I1iii
1.00
3.00
3.870 (4)
146
C11—H11⋯I1i
0.95
2.98
3.930 (3)
174
Symmetry codes: (i) ; (ii) ; (iii) .
Table 3
Hydrogen-bond geometry (Å, °) for salt (3)
D—H⋯A
D—H
H⋯A
D⋯A
D—H⋯A
C1—H1⋯I1i
0.95
2.87
3.744 (2)
153
C2—H2⋯I1ii
0.95
2.94
3.800 (2)
151
C3—H3⋯I1i
1.00
3.18
4.033 (2)
145
Symmetry codes: (i) ; (ii) .
Table 4
Hydrogen-bond geometry (Å, °) for salt (4)
D—H⋯A
D—H
H⋯A
D⋯A
D—H⋯A
C1—H1⋯I1i
0.95
2.85
3.707 (4)
150
C2—H2⋯I1ii
0.95
2.94
3.811 (4)
153
C3—H3B⋯I1iii
0.98
3.10
4.079 (6)
176
Symmetry codes: (i) ; (ii) ; (iii) .
Table 5
Hydrogen-bond geometry (Å, °) for salt (5)
D—H⋯A
D—H
H⋯A
D⋯A
D—H⋯A
C1—H1⋯Br1
0.95
2.59
3.455 (3)
151
C2—H2⋯Br1i
0.95
2.75
3.644 (3)
156
C11—H11⋯O1ii
0.95
2.55
3.247 (4)
130
O1—H1A⋯Br1ii
0.95 (6)
2.42 (6)
3.365 (3)
172 (4)
O1—H1B⋯Br1
0.92 (7)
2.43 (7)
3.341 (3)
170 (5)
Symmetry codes: (i) ; (ii) .
Figure 6
Donor–acceptor interactions of bromide ions and water molecules with each other, with the triazolium C—H, and the ortho C—H of the aryl ring found in salt (5). H atoms not participating in the interactions are not shown. For symmetry codes, see Table 5 ▸.
Salts (1), (2), and (4) pack as layered sheets as shown in Fig. 7 ▸. In salt (1), there is an additional intermolecular interaction between the triazolium carbon and the iodide ion (C1⋯I1) with a distance of 3.546 (4) Å between layers along the unit cell c axis (Fig. 8 ▸). While an anion–π interaction is not common, similar interactions have been reported in the literature, especially in supramolecular systems (Chifotides & Dunbar, 2013 ▸). Each cation in the sheet is further stabilized by an F⋯F interaction with a distance of 2.889 (5) Å between neighboring cations (Fig. 8 ▸). C—F⋯F—Ccontacts are reported in the literature to be weak but still relevant for crystal packing (Chopra, 2012 ▸). In salt (2), the iodide ion between layers is interacting with both the triazolium carbon [C1⋯I1 distance of 3.532 (4) Å, Fig. 9 ▸] and the methinehydrogen atom of the isopropyl group (C3—H3⋯I1, Fig. 9 ▸, Table 2 ▸), in addition to the three hydrogen-bonding interactions with the ortho hydrogen atom and triazoliumhydrogen atom of a cation within the sheet (Figs. 2 ▸ and 9 ▸, Table 2 ▸). Salt (4) also demonstrates iodide ion interaction with both the triazolium carbon [C1⋯I1 distance of 3.503 (3) Å, Fig. 10 ▸] and the methyl hydrogen atom (C3—H3⋯I1; Fig. 10 ▸, Table 4 ▸) in alternating layers, in addition to the hydrogen bonding with the neighboring cation’s triazoliumhydrogen atoms (Fig. 3 ▸, Table 4 ▸). The structure is stabilized further by π–π interactions between aryl carbon atoms in alternating layers [C6⋯C9 with a distance of 3.384 (5) Å] and an aryl carbon atom with a triazolium carbon atom [C1⋯C8 with a distance of 3.282 (4) Å], also in alternating layers (Fig. 10 ▸). In salt (5) there are π-interactions [C11⋯C11 with a distance of 3.220 (5) Å and C1⋯C12 with a distance of 3.335 (4) Å] between triazolium and aryl rings in alternating layers which are closely associated with the donor–acceptor interactions of the bromide ions and water molecules (Figs. 6 ▸ and 11 ▸). Extending the layers further reveals another π–π interaction [C1⋯C13 with a distance of 3.370 (4) Å] between the triazolium cation and aryl rings (Fig. 12 ▸), and a π–π interaction [C2⋯O1, 3.143 (5) Å] between the carbon atom of the triazole ring and the oxygen atom of the water molecule (Fig. 12 ▸
a). This triazole–phenyl π stacking is parallel with the c axis (Fig. 12 ▸
b). The extended sheet network in salt (3) passes diagonally through the cell, but there are no significant intermolecular interactions between cations, as shown in Fig. 13 ▸.
Figure 7
Layered structure observed in the packing of nearly flat cations with iodides. (a) Salt (1) viewed along the a axis; (b) salt (2) viewed along the a axis; and (c) salt (4) viewed along the b axis.
Figure 8
Salt (1) showing intermolecular interactions between layers and neighboring cations. H atoms not participating in intermolecular interactions are not shown. [Symmetry codes: (iv) −x, −y, −z + 1; (v) x − , −y − , z.]
Figure 9
Salt (2) showing intermolecular interactions between layers and neighboring cations. H atoms not participating in intermolecular interactions are not shown. [Symmetry codes: (iv) −x + , y, z + ; (v) −x + , y, z − .]
Figure 10
Salt (4) showing intermolecular interactions between layers and neighboring cations as viewed along the a axis. H atoms not participating in intermolecular interactions are not shown. [Symmetry codes: (iv) x, −y, z − ; (v) x, −y, z + .]
Figure 11
π–π interactions between the triazolium and phenyl rings in salt (5). H atoms not participating in the interactions are omitted. [Symmetry codes: (ii) −x + 2, y, −z + ; (iii) −x + 2, −y, −z; (iv) x, −y, z − .]
Figure 12
(a) Extended π–π interactions between triazolium and phenyl rings in salt (5). (b) Layered structure observed in the packing of nearly flat triazole and phenyl rings with a twisted benzyl ring of the cation in salt (5). H atoms not participating in the interactions are omitted. [Symmetry codes: (ii) −x + 2, y, −z + ; (iii) −x + 2, −y, −z; (iv) x, −y, z − .]
Figure 13
Extended sheet network in salt (3).
Interestingly, when there is para-substitution on the aryl ring [salts (1) and (2)], there are no observed π–π interactions between the phenylene and triazole rings. The observed interactions are predominantly from the triazolium carbon atom with the iodide ion. The absence of the para-substituents allows π–π interactions between the phenyl and triazole rings as demonstrated in salts (4) and (5). However, to facilitate π–π interaction, the aryl ring needs to be co-planar with the triazolium ring; thus there are no π–π interactions in salt (3). Salt (5) exhibited the lowest melting-point temperature, possibly due to the presence of water in the crystal lattice, and thus will not be included in the discussion here. The higher melting points of salts (1), (2) and (4) compared to salt (3) may reflect the layering of the triazolium-aryl cation core sheets and the resulting inter-layer interactions. As predicted by Strassner, the electron-withdrawing substituent in the aryl ring found in salt (1) increased the melting point when compared to salt (2), which contains an electron-donating substituent on the aryl ring (Meyer & Strassner, 2011 ▸). The π–π interactions between the phenyl and triazole rings in salt (4) likely facilitate the increase in melting-point temperature.In summary, for 1-alkyl-4-aryl-1,2,4-triazol-1-ium halide salts, the predominant intermolecular interaction is the C—H⋯halidehydrogen bond between the hydrogen atoms in the triazolium cation and the halide ions forming extended sheets. For salts with para-substitution on the aryl ring, π–π interactions between the triazolium carbon and the halideare present. The melting points of these salts agree with substituent inductive effects predictions. For salts without the para-substitution on the aryl ring, π–π interactions displayed by the layers are between the triazolium and aryl rings.
Database survey
Salt (3) is one of the azolium salts that was utilized by Abdellah in the direct electrochemical reduction of the salt to form the N-heterocycliccarbene (Abdellah et al., 2011 ▸). Salt (4) is a carbene-precursor to phosphorescent platinum(II)–NHCcomplexes; the crystal structure as a carbene ligand is also reported (Tenne et al., 2013 ▸). Triazolium cation (5) was used in the investigation of kinetics and mechanism of azocoupling (Becker et al., 1991 ▸).
Synthesis and crystallization
. All salts were synthesized in two steps. The first step is an intramolecular transamination pathway similar to literature methods (Meyer & Strassner, 2011 ▸; Naik et al., 2008 ▸; Holm et al., 2010 ▸). The products of this transamination step are 4-(4-fluorophenyl)-1,2,4-triazole as the salt (1) precursor, 4-(4-methylphenyl)-1,2,4-triazole as the salt (2) precursor, and 4-(phenyl)-1,2,4-triazole as salts (3), (4) and (5) precursor. In our attempts, we utilized a microwave reactor to shorten the reaction time from 24 hrs to roughly 15–30 mins with 20–70% yields (Meyer & Strassner, 2011 ▸; Naik et al., 2008 ▸; Holm et al., 2010 ▸). The second step is a nucleophilic substitution between the first-step products, 4-aryl-1,2,4-triazoles, and an alkyl halide (2-iodopropane, iodomethane, and benzyl bromide). This synthetic approach was used in the literature (Meyer & Strassner, 2011 ▸; Holm et al., 2010 ▸), but in our attempts we again used the microwave reactor to shorten the reaction time from 48 hrs to 10-30 mins with 10-70% yields (Meyer & Strassner, 2011 ▸; Holm et al., 2010 ▸).N,N-dimethylformamide azine dihydrochloride (DMFA·2HCl) was synthesized following literature methods (Naik et al., 2008 ▸; Holm et al., 2010 ▸). All other reagents and solvents were purchased from Sigma-Aldrich. Tetrahydrofuran (THF) and isopropanol were dried with molecular sieves (4Å). A Biotage microwave reactor was used for all synthetic preparations. All NMR spectra were recorded on a JEOL 400 MHz spectrometer. 1H and 13CNMR chemical shifts were determined by reference to residual 1H and 13C solvent peaks. All thermal analysis experiments were performed on a TA model TGA Q500 thermal gravimetric analyzer and TA model DSC Q100 differential scanning calorimeter. For TGA experiments, crystal samples with masses between 0.4 to 1.4 mg were loaded onto platinum pans. Dry grade nitrogen gas was used for all samples with a balance purge rate of 40.00 mL/min and a sample purge rate of 60.00 mL/min. The temperature was ramped at 20.00 K per minute until a final temperature of 673.00 or 773.00 K was reached. For DSC experiments, crystal samples with masses between 3 and 9 mg were loaded onto platinum pans. Dry grade nitrogen gas was used for all samples with a sample purge range of 50.00 mL/min. The samples were subjected to a heat/cool/heat cycle with a temperature ramp rate of 10.00 K per minute until a final temperature of 473–523 K was reached for the heating cycle, and a temperature ramp rate of 5.00 K per minute until a final temperature of 273 or 248 K was reached for the cooling cycle.A 20 mL microwave reaction vessel with a stir bar was charged with 1:1 molar equivalents of N,N-dimethylformamide azine dihydrochloride (DMFA·2HCl), and a para-substituted aryl amine (4-fluoroaniline or p-toluidine), or aniline. The microwave was set to 443 or 453 K at normal absorbance, and run for 10–30 mins. Once completed, the mixture was washed with THF, dried with anhydrous magnesium sulfate and filtered. The solvent was removed in vacuo, and the remaining solid was washed with diethyl ether.
4-(4-fluorophenyl)-1,2,4-triazole. Brown oil (1.09 g, 72% yield).1HNMR (400 MHz, CDCl3): δ 8.44 (s, 2H, CH), 7.40–7.38 (m, 2H, Ar), 7.27–7.23 (m, 3H, Ar).
4-(4-methylphenyl)-1,2,4-triazole. Brown solid (0.26 g, 27% yield). 1HNMR (400 MHz, CDCl3): δ 8.45 (s, 2H, CH), 7.35–7.32 (d, 2H, Ar), 7.28–7.2 (d, 2H, Ar), 2.43 (s, 3H, Me). The proton spectrum values are the same as the literature values (Holm et al., 2010 ▸).
4-phenyl-1,2,4-triazole. Brown solid (0.303 g, 22% yield). 1HNMR(400 MHz, CDCl3): δ 8.46 (s, 2H, CH), 7.54–7.49 (m, 2H, Ar) 7.47–7.42 (m, 1H, Ar), 7.39–7.36 (m, 2H, Ar). 13CNMR (101 MHz, CDCl3): δ 141.5, 133.9, 130.4, 129.1, 122.2. The proton and carbon spectra are the same as the literature values (Meyer & Strassner, 2011 ▸; Holm, et al., 2010 ▸).A 20 mL microwave reaction vessel with a stir bar was charged with 1:2 molar equivalents of 4-aryl-1,2,4-triazole, a halide-substituted alkyl group (2-iodopropane, iodomethane, and benzyl bromide), and THF (5 mL). The microwave was set to 393–433 K at high absorbance for 10–30 mins. The resulting mixture was vacuum filtered, and washed with diethyl ether (3 × 10 mL). The solid product was recrystallized from hot isopropanol and placed in the refrigerator for several days. Salt (1): 1-isopropyl-4-(4-fluorophenyl)-1,2,4-triazol-1-ium iodide. Needle-like colorless crystals (0.070 g, 11% yield). 1HNMR (400 MHz, DMSO-d
6): δ 10.70 (s, 1H, CH), 9.73 (s, 1H, CH), 7.94–7.90 (dd, 2H, Ar), 7.63–7.60 (dd, 2H, Ar), 4.84–4.82 (sept, 1H, iPr), 1.61–1.59 (d, 6H, iPr).13CNMR (101 MHz, DMSO-d
6): δ 164.0, 161.5, 143.1, 140.8, 128.8, 125.5, 117.3, 117.1, 55.8, 21.3. Decomposition temp: 516.4 K. Salt (2): 1-isopropyl-4-(4-methylphenyl)-1,2,4-triazol-1-ium iodide. Colorless prismaticcrystals (0.22 g, 54% yield). 1HNMR (400 MHz, DMSO-d
6): δ 10.68 (s, 1H, CH), 9.73 (s, 1H,) , 7.75–7.72 (dd, 2H, Ar), 7.71–7.50 (d, 2H, Ar), 4.88-4.78 (sept, 1H, iPr), 2.41 (s, 3H, Me), 1.60–1.58 (d, 6H, iPr).13CNMR (101 MHz, DMSO-d
6): δ 142.7, 140.3, 140.2, 130.4, 129.8, 122.3, 55.6, 21.1, 20.7. Decomposition temp: 500.4 K. Salt (3): 1-isopropyl-4-phenyl-1,2,4-triazol-1-ium iodide. Colorless prismaticcrystals (0.107 g, 24% yield). 1HNMR (400 MHz, DMSO-d
6): δ 10.73 (s, 1H, CH), 9.77 (s, 1H, CH), 7.86–7.85 (d, 2H, Ar), 7.73–7.69 (t, 2H, Ar), 7.66–7.62 (t, 1H, Ar), 4.88–4.81 (sept, 1H, iPr), 1.60–1.58 (d, 6H, Me). 13CNMR (101 MHz, DMSO-d
6): δ 142.8, 140.4, 132.2, 130.5, 130.2, 122.6, 55.7, 21.2. Decomposition temp: 500.9 K. Salt (4): 1-methyl-4-phenyl-1,2,4-triazol-1-ium iodide. Colorless prism crystals (0.144 g, 70% yield). 1HNMR (400 MHz, DMSO-d
6): δ 10.77 (s, 1H, CH), 9.76 (s, 1H, CH), 7.84–7.81 (dt, 2H, Ar), 7.73–7.66 (tt, 2H, Ar), 7.65–7.62 (tt, 1H, Ar), 4.15 (s, 3H, Me). 13CNMR (101 MHz, DMSO-d
6): δ 142.7, 142.0, 132.1, 130.6, 130.3, 122.5, 39.0. Decomposition temp: 506.2 K.The proton and carbon spectroscopic values are the same as the literature values (Tenne et al., 2013 ▸). Salt (5): 1-benzyl-4-phenyl-1,2,4-triazol-1-ium bromide. Colorless prismaticcrystals (0.065 g, 10% yield).1HNMR (400 MHz, DMSO-d
6) δ 11.05 (s, 1H, CH), 9.81 (s, 1H, CH), 7.87–7.84 (dt, 1H, Ar), 7.85–7.84 (dd, 1H, Ar), 7.72–7.68 (tt, 2H, Ar), 7.66–7.62 (tt, 1H, Ar), 7.56 (m, 2H, Bn), 7.47–7.41 (m, 3H, Bn), 5.71 (s, 2H, CH2). 13CNMR (101 MHz, DMSO-d
6) δ 143.4, 141.9, 133.0, 132.2, 130.5, 130.2, 129.1, 129.0, 128.9, 122.6, 55.2. Decomposition temp: 431.8 K.Melting points: salt (1), m.p.: 512.8 K; salt (2), m.p.: 489.4 K; salt (3), m.p.: 455.3 K; salt (4), m.p.: 505.7 K; salt (5), m.p.: 389.2 K.
Refinement
Crystal data, data collection and structure refinement details are summarized in Table 6 ▸. H atoms for salts (1)–(4) were placed in calculated positions and allowed to ride on their parent atoms at C—H distances of 0.95 Å for the triazolium and aryl rings, 0.98 Å for the methyl groups, and 1.00 Å for the methine group. H atoms for salt (5) were treated with a mixture of independent and constrained refinement. The C—H distances are 0.95 Å for the triazolium and aryl rings, 0.99 Å for the methylene group, and 0.95 (6) Å and 0.92 (7) Å for water. Salt (4) crystallized in the non-centrosymmetric space group Cc with a Flack parameter of −0.01 (2) indicating the absolute structure is well determined.Crystal structure: contains datablock(s) salt1, salt2, salt3, salt4, salt5. DOI: 10.1107/S2056989015009019/zl2623sup1.cifStructure factors: contains datablock(s) salt1. DOI: 10.1107/S2056989015009019/zl2623salt1sup2.hklClick here for additional data file.Supporting information file. DOI: 10.1107/S2056989015009019/zl2623salt1sup7.cmlStructure factors: contains datablock(s) salt2. DOI: 10.1107/S2056989015009019/zl2623salt2sup3.hklStructure factors: contains datablock(s) salt3. DOI: 10.1107/S2056989015009019/zl2623salt3sup4.hklStructure factors: contains datablock(s) salt4. DOI: 10.1107/S2056989015009019/zl2623salt4sup5.hklStructure factors: contains datablock(s) salt5. DOI: 10.1107/S2056989015009019/zl2623salt5sup6.hklClick here for additional data file.Supporting information file. DOI: 10.1107/S2056989015009019/zl2623salt2sup8.cmlClick here for additional data file.Supporting information file. DOI: 10.1107/S2056989015009019/zl2623salt3sup9.cmlClick here for additional data file.Supporting information file. DOI: 10.1107/S2056989015009019/zl2623salt4sup10.cmlClick here for additional data file.Supporting information file. DOI: 10.1107/S2056989015009019/zl2623salt5sup11.cmlCCDC references: 1400159, 1400158, 1400157, 1400156, 1400155Additional supporting information: crystallographic information; 3D view; checkCIF report
Hydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.035
H-atom parameters constrained
wR(F2) = 0.077
w = 1/[σ2(Fo2) + (0.0311P)2 + 1.7321P] where P = (Fo2 + 2Fc2)/3
S = 1.03
(Δ/σ)max < 0.001
2632 reflections
Δρmax = 0.60 e Å−3
147 parameters
Δρmin = −0.58 e Å−3
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.
Hydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.031
H-atom parameters constrained
wR(F2) = 0.065
w = 1/[σ2(Fo2) + (0.0241P)2 + 1.7237P] where P = (Fo2 + 2Fc2)/3
S = 1.04
(Δ/σ)max = 0.001
2767 reflections
Δρmax = 0.43 e Å−3
148 parameters
Δρmin = −0.36 e Å−3
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.
Hydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.023
H-atom parameters constrained
wR(F2) = 0.055
w = 1/[σ2(Fo2) + (0.0167P)2 + 0.5394P] where P = (Fo2 + 2Fc2)/3
S = 1.09
(Δ/σ)max = 0.002
2858 reflections
Δρmax = 0.40 e Å−3
138 parameters
Δρmin = −0.69 e Å−3
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.
Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full
H-atom parameters constrained
R[F2 > 2σ(F2)] = 0.018
w = 1/[σ2(Fo2) + (0.0128P)2] where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.037
(Δ/σ)max < 0.001
S = 1.05
Δρmax = 0.18 e Å−3
2420 reflections
Δρmin = −0.36 e Å−3
119 parameters
Absolute structure: Flack x determined using 1112 quotients
[(I+)-(I-)]/[(I+)+(I-)]
(Parsons et al., 2013)
2 restraints
Absolute structure parameter: −0.012 (18)
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.
H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.098
w = 1/[σ2(Fo2) + (0.0376P)2 + 4.9222P] where P = (Fo2 + 2Fc2)/3
S = 1.08
(Δ/σ)max < 0.001
3259 reflections
Δρmax = 0.75 e Å−3
189 parameters
Δρmin = −0.63 e Å−3
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.
x
y
z
Uiso*/Ueq
Br1
0.91115 (2)
0.40151 (3)
0.12909 (3)
0.03409 (12)
O1
0.95493 (13)
0.3722 (3)
0.3846 (2)
0.0497 (7)
N1
0.93559 (9)
−0.0969 (2)
0.07656 (16)
0.0202 (5)
N2
0.85547 (9)
−0.0072 (2)
0.02922 (17)
0.0230 (5)
N3
0.84900 (10)
−0.1587 (3)
0.0213 (2)
0.0310 (6)
C1
0.90660 (11)
0.0297 (3)
0.0619 (2)
0.0218 (6)
H1
0.9206
0.1278
0.0731
0.026*
C2
0.89834 (12)
−0.2097 (3)
0.0504 (2)
0.0282 (6)
H2
0.9075
−0.3123
0.0533
0.034*
C3
0.80795 (12)
0.0930 (3)
0.0032 (2)
0.0272 (6)
H3A
0.7870
0.0662
−0.0657
0.033*
H3B
0.8210
0.1966
−0.0005
0.033*
C4
0.77094 (11)
0.0834 (3)
0.0831 (2)
0.0228 (6)
C5
0.78422 (12)
0.1609 (3)
0.1760 (2)
0.0279 (6)
H5
0.8160
0.2219
0.1883
0.034*
C6
0.75109 (13)
0.1493 (3)
0.2505 (2)
0.0339 (7)
H6
0.7605
0.2008
0.3145
0.041*
C7
0.70429 (12)
0.0627 (3)
0.2321 (2)
0.0310 (7)
H7
0.6817
0.0544
0.2834
0.037*
C8
0.69055 (13)
−0.0116 (4)
0.1389 (3)
0.0357 (7)
H8
0.6581
−0.0697
0.1257
0.043*
C9
0.72382 (12)
−0.0019 (3)
0.0647 (2)
0.0306 (7)
H9
0.7143
−0.0539
0.0009
0.037*
C10
0.99369 (11)
−0.1085 (3)
0.11401 (19)
0.0219 (6)
C11
1.02340 (12)
0.0196 (3)
0.1428 (2)
0.0248 (6)
H11
1.0060
0.1140
0.1367
0.030*
C12
1.07896 (12)
0.0078 (3)
0.1805 (2)
0.0289 (6)
H12
1.0999
0.0947
0.2007
0.035*
C13
1.10438 (13)
−0.1303 (4)
0.1889 (2)
0.0321 (7)
H13
1.1425
−0.1380
0.2151
0.038*
C14
1.07384 (13)
−0.2566 (4)
0.1590 (2)
0.0360 (7)
H14
1.0912
−0.3511
0.1645
0.043*
C15
1.01828 (12)
−0.2467 (3)
0.1210 (2)
0.0310 (7)
H15
0.9974
−0.3334
0.1001
0.037*
H1A
0.992 (2)
0.389 (5)
0.377 (4)
0.086 (17)*
H1B
0.939 (3)
0.372 (7)
0.315 (5)
0.13 (3)*
U11
U22
U33
U12
U13
U23
Br1
0.0347 (2)
0.02343 (17)
0.0440 (2)
−0.00110 (13)
0.00651 (13)
−0.00295 (13)
O1
0.0535 (18)
0.0457 (15)
0.0542 (18)
0.0036 (13)
0.0215 (14)
0.0063 (13)
N1
0.0236 (12)
0.0192 (11)
0.0183 (10)
0.0007 (9)
0.0051 (9)
−0.0014 (9)
N2
0.0225 (13)
0.0221 (12)
0.0251 (12)
0.0027 (9)
0.0060 (10)
−0.0001 (9)
N3
0.0275 (14)
0.0210 (12)
0.0435 (15)
0.0013 (10)
0.0034 (11)
−0.0025 (11)
C1
0.0252 (15)
0.0185 (13)
0.0225 (13)
0.0019 (11)
0.0059 (11)
−0.0009 (10)
C2
0.0275 (16)
0.0201 (14)
0.0366 (16)
−0.0003 (12)
0.0044 (12)
−0.0026 (12)
C3
0.0237 (15)
0.0290 (15)
0.0287 (14)
0.0070 (12)
0.0039 (11)
0.0062 (12)
C4
0.0188 (14)
0.0224 (14)
0.0265 (14)
0.0070 (11)
0.0021 (11)
0.0042 (11)
C5
0.0215 (15)
0.0298 (15)
0.0316 (15)
−0.0024 (12)
0.0018 (12)
−0.0013 (12)
C6
0.0359 (18)
0.0369 (17)
0.0286 (15)
0.0007 (14)
0.0047 (13)
−0.0028 (13)
C7
0.0266 (16)
0.0319 (16)
0.0361 (17)
0.0041 (12)
0.0101 (13)
0.0057 (13)
C8
0.0233 (16)
0.0350 (18)
0.049 (2)
−0.0060 (13)
0.0068 (14)
0.0003 (15)
C9
0.0256 (16)
0.0309 (16)
0.0340 (16)
−0.0005 (12)
0.0014 (13)
−0.0059 (13)
C10
0.0235 (14)
0.0284 (14)
0.0144 (12)
0.0017 (11)
0.0050 (10)
0.0008 (10)
C11
0.0280 (16)
0.0260 (15)
0.0201 (13)
−0.0021 (12)
0.0036 (11)
0.0024 (11)
C12
0.0280 (16)
0.0380 (17)
0.0204 (13)
−0.0063 (13)
0.0039 (11)
0.0009 (12)
C13
0.0255 (16)
0.0476 (19)
0.0226 (14)
0.0063 (13)
0.0027 (12)
0.0032 (13)
C14
0.0331 (18)
0.0334 (17)
0.0403 (18)
0.0106 (14)
0.0027 (14)
0.0006 (14)
C15
0.0290 (17)
0.0265 (15)
0.0358 (16)
0.0054 (12)
0.0009 (13)
−0.0023 (13)
O1—H1A
0.95 (6)
C6—C7
1.382 (4)
O1—H1B
0.92 (7)
C6—H6
0.9500
N1—C1
1.342 (3)
C7—C8
1.381 (4)
N1—C2
1.375 (4)
C7—H7
0.9500
N1—C10
1.441 (4)
C8—C9
1.382 (4)
N2—C1
1.307 (3)
C8—H8
0.9500
N2—N3
1.374 (3)
C9—H9
0.9500
N2—C3
1.475 (3)
C10—C15
1.380 (4)
N3—C2
1.299 (4)
C10—C11
1.384 (4)
C1—H1
0.9500
C11—C12
1.383 (4)
C2—H2
0.9500
C11—H11
0.9500
C3—C4
1.508 (4)
C12—C13
1.388 (4)
C3—H3A
0.9900
C12—H12
0.9500
C3—H3B
0.9900
C13—C14
1.383 (5)
C4—C9
1.383 (4)
C13—H13
0.9500
C4—C5
1.391 (4)
C14—C15
1.383 (4)
C5—C6
1.384 (4)
C14—H14
0.9500
C5—H5
0.9500
C15—H15
0.9500
H1A—O1—H1B
98 (5)
C5—C6—H6
119.9
C1—N1—C2
105.8 (2)
C8—C7—C6
119.8 (3)
C1—N1—C10
126.0 (2)
C8—C7—H7
120.1
C2—N1—C10
128.2 (2)
C6—C7—H7
120.1
C1—N2—N3
111.7 (2)
C7—C8—C9
120.3 (3)
C1—N2—C3
127.5 (2)
C7—C8—H8
119.8
N3—N2—C3
120.7 (2)
C9—C8—H8
119.8
C2—N3—N2
103.7 (2)
C8—C9—C4
120.1 (3)
N2—C1—N1
107.2 (2)
C8—C9—H9
119.9
N2—C1—H1
126.4
C4—C9—H9
119.9
N1—C1—H1
126.4
C15—C10—C11
121.6 (3)
N3—C2—N1
111.7 (3)
C15—C10—N1
119.4 (2)
N3—C2—H2
124.2
C11—C10—N1
119.0 (2)
N1—C2—H2
124.2
C12—C11—C10
118.8 (3)
N2—C3—C4
111.3 (2)
C12—C11—H11
120.6
N2—C3—H3A
109.4
C10—C11—H11
120.6
C4—C3—H3A
109.4
C11—C12—C13
120.4 (3)
N2—C3—H3B
109.4
C11—C12—H12
119.8
C4—C3—H3B
109.4
C13—C12—H12
119.8
H3A—C3—H3B
108.0
C14—C13—C12
119.6 (3)
C9—C4—C5
119.6 (3)
C14—C13—H13
120.2
C9—C4—C3
120.6 (3)
C12—C13—H13
120.2
C5—C4—C3
119.8 (3)
C15—C14—C13
120.7 (3)
C6—C5—C4
120.0 (3)
C15—C14—H14
119.7
C6—C5—H5
120.0
C13—C14—H14
119.7
C4—C5—H5
120.0
C10—C15—C14
118.8 (3)
C7—C6—C5
120.2 (3)
C10—C15—H15
120.6
C7—C6—H6
119.9
C14—C15—H15
120.6
C1—N2—N3—C2
−0.1 (3)
C6—C7—C8—C9
1.1 (5)
C3—N2—N3—C2
−179.6 (2)
C7—C8—C9—C4
−0.5 (5)
N3—N2—C1—N1
0.0 (3)
C5—C4—C9—C8
−0.9 (4)
C3—N2—C1—N1
179.4 (2)
C3—C4—C9—C8
179.1 (3)
C2—N1—C1—N2
0.1 (3)
C1—N1—C10—C15
−177.3 (3)
C10—N1—C1—N2
−178.9 (2)
C2—N1—C10—C15
4.0 (4)
N2—N3—C2—N1
0.2 (3)
C1—N1—C10—C11
3.1 (4)
C1—N1—C2—N3
−0.1 (3)
C2—N1—C10—C11
−175.6 (3)
C10—N1—C2—N3
178.8 (2)
C15—C10—C11—C12
−0.7 (4)
C1—N2—C3—C4
−108.9 (3)
N1—C10—C11—C12
178.8 (2)
N3—N2—C3—C4
70.5 (3)
C10—C11—C12—C13
0.2 (4)
N2—C3—C4—C9
−99.5 (3)
C11—C12—C13—C14
0.3 (4)
N2—C3—C4—C5
80.5 (3)
C12—C13—C14—C15
−0.2 (5)
C9—C4—C5—C6
1.7 (4)
C11—C10—C15—C14
0.8 (4)
C3—C4—C5—C6
−178.3 (3)
N1—C10—C15—C14
−178.8 (2)
C4—C5—C6—C7
−1.1 (5)
C13—C14—C15—C10
−0.3 (5)
C5—C6—C7—C8
−0.3 (5)
D—H···A
D—H
H···A
D···A
D—H···A
C1—H1···Br1
0.95
2.59
3.455 (3)
151
C2—H2···Br1i
0.95
2.75
3.644 (3)
156
C11—H11···O1ii
0.95
2.55
3.247 (4)
130
O1—H1A···Br1ii
0.95 (6)
2.42 (6)
3.365 (3)
172 (4)
O1—H1B···Br1
0.92 (7)
2.43 (7)
3.341 (3)
170 (5)
Salt (1)
Salt (2)
Salt (3)
Crystal data
Chemical formula
C11H13FN3+·I−
C12H16N3+·I−
C11H14N3+·I−
Mr
333.14
329.18
315.15
Crystal system, space group
Orthorhombic, Pccn
Orthorhombic, Pccn
Monoclinic, P21/n
Temperature (K)
173
173
173
a, b, c (Å)
16.396 (3), 21.732 (4), 7.2412 (12)
15.843 (3), 21.933 (4), 7.8250 (14)
5.9326 (11), 17.826 (3), 12.129 (2)
α, β, γ (°)
90, 90, 90
90, 90, 90
90, 102.897 (7), 90
V (Å3)
2580.1 (7)
2719.0 (8)
1250.3 (4)
Z
8
8
4
Radiation type
Mo Kα
Mo Kα
Mo Kα
μ (mm−1)
2.47
2.34
2.54
Crystal size (mm)
0.71 × 0.05 × 0.02
0.52 × 0.12 × 0.04
0.80 × 0.40 × 0.10
Data collection
Diffractometer
Rigaku XtaLAB mini
Rigaku XtaLAB mini
Rigaku XtaLAB mini
Absorption correction
Multi-scan (REQAB; Rigaku, 1998 ▸)
Multi-scan (REQAB; Rigaku, 1998 ▸)
Multi-scan (REQAB; Rigaku, 1998 ▸)
Tmin, Tmax
0.671, 0.952
0.564, 0.911
0.356, 0.776
No. of measured, independent and observed [I > 2σ(I)] reflections
17829, 2632, 1872
16099, 2767, 2150
12823, 2858, 2582
Rint
0.073
0.051
0.044
(sin θ/λ)max (Å−1)
0.625
0.625
0.649
Refinement
R[F2 > 2σ(F2)], wR(F2), S
0.035, 0.077, 1.03
0.031, 0.065, 1.04
0.023, 0.055, 1.09
No. of reflections
2632
2767
2858
No. of parameters
147
148
138
No. of restraints
0
0
0
H-atom treatment
H-atom parameters constrained
H-atom parameters constrained
H-atom parameters constrained
Δρmax, Δρmin (e Å−3)
0.60, −0.58
0.43, −0.36
0.40, −0.69
Salt (4)
Salt (5)
Crystal data
Chemical formula
C9H10N3+·I−
C15H14N3+·Br−·H2O
Mr
287.10
334.22
Crystal system, space group
Monoclinic, Cc
Monoclinic, C2/c
Temperature (K)
173
173
a, b, c (Å)
7.660 (2), 16.912 (5), 8.412 (3)
24.783 (6), 8.996 (2), 13.089 (3)
α, β, γ (°)
90, 101.137 (7), 90
90, 100.068 (7), 90
V (Å3)
1069.2 (6)
2873.3 (13)
Z
4
8
Radiation type
Mo Kα
Mo Kα
μ (mm−1)
2.96
2.86
Crystal size (mm)
0.31 × 0.23 × 0.13
0.60 × 0.37 × 0.17
Data collection
Diffractometer
Rigaku XtaLAB mini
Rigaku XtaLAB mini
Absorption correction
Multi-scan (REQAB; Rigaku, 1998 ▸)
Multi-scan (REQAB; Rigaku, 1998 ▸)
Tmin, Tmax
0.439, 0.681
0.321, 0.614
No. of measured, independent and observed [I > 2σ(I)] reflections
5472, 2420, 2359
6672, 3259, 2630
Rint
0.020
0.031
(sin θ/λ)max (Å−1)
0.649
0.650
Refinement
R[F2 > 2σ(F2)], wR(F2), S
0.018, 0.037, 1.05
0.043, 0.098, 1.08
No. of reflections
2420
3259
No. of parameters
119
189
No. of restraints
2
0
H-atom treatment
H-atom parameters constrained
H atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3)
0.18, −0.36
0.75, −0.63
Absolute structure
Flack x determined using 1112 quotients [(I+)−(I−)]/[(I+)+(I−)] (Parsons et al., 2013 ▸)
–
Absolute structure parameter
−0.012 (18)
–
Computer programs: CrystalClearSM Expert (Rigaku, 2011 ▸), SIR97 (Altomare et al., 1999 ▸), SHELXL2014 (Sheldrick, 2015 ▸), CrystalStructure (Rigaku, 2010 ▸) and Mercury (Macrae et al., 2006 ▸).