research communications
and Hirshfeld surface analysis of 4-bromoanilinium nitrate
aMaterials Science Laboratory, Department of Physics, Periyar University, Salem, India, and bDepartment of Physics, Jimma University, Jimma, Ethiopia
*Correspondence e-mail: menberu.mengesha@ju.edu.et
The title compound C4H7BrN+·NO3− crystallizes in the monoclinic with P21/c. In the crystal, π-π stacking interactions and strong N—H⋯O and C—H⋯O hydrogen bonds link the cations and anions into layers parallel to the bc plane. The O⋯H/H⋯O interactions between the cation and anion are the major factor determining the crystal packing.
Keywords: crystal structure; Hirshfeld surface; hydrogen bonds; aniline.
CCDC reference: 1909800
1. Chemical context
In recent years, halogenated anilines and their derivatives have been studied extensively for applications as anticorrosives, antibacterials and in non-linear optical systems (Glidewell et al., 2005; Vivek et al., 2014). The simplest halogenated aniline readily forms metal/non-metal complexes (Hartmann et al., 1990). Strong hydrogen bonding, non-covalent bonding and π–π stacking interactions are prominent in the supramolecular arrangements of this molecule. Here, we report the of 4-bromoanilinium nitrate, a salt complex whose structure is closely related to its 4-iodo analogue regarding the hydrogen-bond networks and π–π interactions (Fu et al., 2010) although having significantly different unit-cell parameters.
2. Structural commentary
The ii, N2—H13⋯O3iv and a bifurcated N1—H9⋯O2i/N1—H9⋯O3i hydrogen bonds (Fig. 1). This motif generates a van der Waals contact (O3⋯O6) of 2.980 (4) Å between the two nitrate ions. The phenyl rings in the independent cations extend in the same direction from the pair of anions with a dihedral angle of only 4.8 (2)° between their mean planes and participate in a π–π stacking interaction with a centroid⋯centroid distance of 3.932 (2) Å. Meanwhile, one cation is rotated with respect to the other so that the Br1—C2⋯C10—Br2 torsion angle is 50.4 (su?)°.
consists of two 4-bromoanilinium cations and two nitrate anions which are associated through N1—H10⋯O43. Supramolecular features
In the crystal, the anions are arranged in coarsely corrugated layers parallel to the bc plane with the hydrogen-bonded cations protruding from each face in an alternating fashion (Fig. 2). The cations containing Br1 are perpendicular to the layers and make close Br1⋯O5 contacts of 3.229 (5) Å (0.14 Å less than the sum of the van der Waals radii) with nitrate ions in adjacent layers (Fig. 2, Table 1).
4. Hirshfeld surface analysis
The intermolecular interactions were investigated quantitatively and visualized with Crystal Explorer 3.1 (Wolff et al., 2012; Spackman et al., 2009). The dnorm, curvedness and 2D fingerprint plots are depicted in Figs. 3–5, respectively. The red spots on the Hirshfeld surface represent N—H⋯O contacts (Br⋯O contacts are not visible as red spots) while the blue regions correspond to weak interactions such as C—H⋯O contacts. The two triangles in the curvedness surface clearly illustrate the π–π stacking interactions. The O⋯H/H⋯O (51.4%) interactions are the major factor in the crystal packing with H⋯H (15.5%) interactions representing the next highest contribution. The percentage contributions of other weak interactions are: H⋯Br/Br⋯H (10.3%), C⋯H/H⋯C (9.2%), O⋯Br/Br⋯O (4.1%), Br⋯Br (2.7%), N⋯H/H⋯N (1.7%), O⋯O (1.6%), C⋯C (1.5%), C⋯O/O⋯C (0.8%), N⋯Br/Br⋯N (0.4), C⋯Br/Br⋯C (0.4%), N⋯O/O⋯N (0.3%) and N⋯C/C⋯N (0.1%).
4.1. Database survey
A search of the Cambridge Structural Database (CSD version 5.41, last update April 2020; Groom et al., 2016) for the 4-bromoanilinium cation gave 22 hits excluding metal complexes. Among these, 13 structures have this cation combined with various acid anions including [PO2(OH)2]− (EBEFAV; Yoshii et al., 2015; UGISEI; Zhang et al., 2001; UGISEI01; Yoshii et al., 2015), [HC2O4]− (ROBXOY; Radhakrishnan & Jeyaperumal, 2019), [C4H5O6]− (ROPTEX; Yoshii et al., 2014) and [p-CH3C6H4SO3]− (VUCBAY; Sivakumar et al., 2015). Two more have amide anions [N(SO2R)2]− [R = Me (TAJWOT; Jones et al., 2016), 4-BrC6H4 (DOHSOJ; Lozano et al., 2008)]. The remainder have inorganic anions such as [SiF6]2− (PBANIL; Denne et al., 1971), [PF6]− (TUPWUX; Yang & Fu, 2010) and chloride (TAWRAL; Portalone, 2005). Additionally, there is an unpublished structure of the title compound (ROCNOP; Anbarasan & Sundar, 2019) of comparable quality to the present study but without the additional investigations presented here.
5. Synthesis and crystallization
The title salt was synthesized by dissolving analytical grade 4-bromoaniline and nitric acid in a 1:1 stoichiometric ratio in methanol. The solution was stirred continuously for 2 h. Slow evaporation of this solution at room temperature yielded transparent colourless single crystals of the product.
6. Refinement
Crystal data, data collection and structure . The H atoms were positioned geometrically and refined using a riding model: C—H = 0.93 Å with Uiso(H) = 1.2Ueq(C) and N—H = 0.86 Å with Uiso(H) = 1.2Ueq(N). Reflection (100) was obscured by the beam stop and was omitted during the final cycle.
details are summarized in Table 2
|
Supporting information
CCDC reference: 1909800
https://doi.org/10.1107/S2056989020006945/mw2155sup1.cif
contains datablocks global, I. DOI:Supporting information file. DOI: https://doi.org/10.1107/S2056989020006945/mw2155Isup2.cml
Data collection: APEX2 (Bruker, 2004); cell
SAINT (Bruker, 2004); data reduction: SAINT (Bruker, 2004); program(s) used to solve structure: SHELXT (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2017 (Sheldrick, 2015b); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: WinGX (Farrugia, 2012), PLATON (Spek, 2020), Mercury (Macrae et al., 2020) and publCIF (Westrip, 2010).C6H7BrN+·NO3− | F(000) = 928 |
Mr = 235.04 | Dx = 1.808 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 4609 reflections |
a = 9.7123 (8) Å | θ = 2.6–29.1° |
b = 23.4964 (19) Å | µ = 4.73 mm−1 |
c = 7.6264 (6) Å | T = 293 K |
β = 97.052 (4)° | Needle, colorless |
V = 1727.2 (2) Å3 | 0.42 × 0.18 × 0.12 mm |
Z = 8 |
Bruker SMART APEXII CCD diffractometer | 2355 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.058 |
ω and φ scan | θmax = 29.1°, θmin = 2.1° |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | h = −13→11 |
Tmin = 0.374, Tmax = 0.567 | k = −29→32 |
16821 measured reflections | l = −8→10 |
4609 independent reflections |
Refinement on F2 | Hydrogen site location: inferred from neighbouring sites |
Least-squares matrix: full | H-atom parameters constrained |
R[F2 > 2σ(F2)] = 0.059 | w = 1/[σ2(Fo2) + (0.0927P)2 + 0.2455P] where P = (Fo2 + 2Fc2)/3 |
wR(F2) = 0.183 | (Δ/σ)max < 0.001 |
S = 1.02 | Δρmax = 0.68 e Å−3 |
4609 reflections | Δρmin = −0.84 e Å−3 |
218 parameters | Extinction correction: SHELXL2018/3 (Sheldrick 2015b) |
0 restraints | Extinction coefficient: 0.0181 (17) |
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. |
x | y | z | Uiso*/Ueq | ||
N1 | 1.0463 (4) | 0.32338 (12) | 0.2075 (4) | 0.0513 (8) | |
H10 | 1.083534 | 0.351431 | 0.150589 | 0.077* | |
H9 | 1.063697 | 0.329131 | 0.323465 | 0.077* | |
H11 | 1.082988 | 0.290327 | 0.180092 | 0.077* | |
N2 | 0.8383 (4) | 0.52952 (13) | 0.2737 (5) | 0.0571 (9) | |
H14 | 0.798745 | 0.556374 | 0.202137 | 0.086* | |
H13 | 0.880154 | 0.545557 | 0.371772 | 0.086* | |
H12 | 0.900523 | 0.510739 | 0.219564 | 0.086* | |
N3 | 0.0880 (3) | 0.32409 (14) | 0.6621 (5) | 0.0481 (8) | |
N4 | 0.1286 (3) | 0.46630 (13) | 0.1594 (5) | 0.0531 (9) | |
O2 | 0.1085 (4) | 0.28155 (12) | 0.5705 (5) | 0.0762 (10) | |
O3 | 0.0604 (4) | 0.36877 (12) | 0.5772 (5) | 0.0891 (12) | |
O4 | 0.1736 (3) | 0.42637 (11) | 0.0733 (4) | 0.0613 (8) | |
O5 | 0.0995 (5) | 0.32142 (18) | 0.8212 (5) | 0.0941 (12) | |
O6 | 0.0681 (3) | 0.45499 (12) | 0.2920 (4) | 0.0656 (8) | |
O1 | 0.1429 (4) | 0.51579 (11) | 0.1125 (5) | 0.0766 (10) | |
C1 | 0.6768 (5) | 0.28047 (18) | 0.1770 (6) | 0.0632 (12) | |
H1 | 0.622297 | 0.253605 | 0.225586 | 0.076* | |
C2 | 0.6166 (5) | 0.31894 (18) | 0.0536 (5) | 0.0549 (11) | |
C3 | 0.6968 (5) | 0.35869 (17) | −0.0173 (6) | 0.0611 (12) | |
H2 | 0.655897 | 0.384689 | −0.099684 | 0.073* | |
C4 | 0.8371 (5) | 0.36032 (15) | 0.0328 (5) | 0.0539 (11) | |
H3 | 0.891543 | 0.387124 | −0.016287 | 0.065* | |
C5 | 0.8970 (4) | 0.32216 (14) | 0.1558 (5) | 0.0449 (9) | |
C6 | 0.8179 (5) | 0.28202 (17) | 0.2278 (6) | 0.0576 (11) | |
H4 | 0.859217 | 0.256095 | 0.310167 | 0.069* | |
C7 | 0.7319 (4) | 0.48981 (15) | 0.3193 (5) | 0.0466 (9) | |
C8 | 0.5964 (5) | 0.49725 (19) | 0.2493 (6) | 0.0638 (12) | |
H5 | 0.571499 | 0.527478 | 0.173184 | 0.077* | |
C9 | 0.4971 (5) | 0.4596 (2) | 0.2925 (7) | 0.0779 (14) | |
H6 | 0.40465 | 0.463954 | 0.245794 | 0.094* | |
C10 | 0.5363 (5) | 0.4159 (2) | 0.4046 (6) | 0.0640 (12) | |
C11 | 0.6718 (5) | 0.40804 (19) | 0.4725 (6) | 0.0607 (11) | |
H7 | 0.696645 | 0.377689 | 0.548105 | 0.073* | |
C12 | 0.7710 (4) | 0.44517 (19) | 0.4285 (5) | 0.0562 (11) | |
H8 | 0.863752 | 0.439985 | 0.472598 | 0.067* | |
Br1 | 0.42315 (6) | 0.31590 (3) | −0.02005 (7) | 0.0826 (3) | |
Br2 | 0.40126 (7) | 0.36433 (3) | 0.47100 (8) | 0.1017 (3) |
U11 | U22 | U33 | U12 | U13 | U23 | |
N1 | 0.070 (2) | 0.0398 (16) | 0.0435 (19) | −0.0049 (16) | 0.0034 (17) | −0.0031 (14) |
N2 | 0.056 (2) | 0.0473 (19) | 0.065 (2) | 0.0020 (16) | −0.0038 (17) | −0.0121 (17) |
N3 | 0.0476 (19) | 0.0412 (18) | 0.054 (2) | −0.0059 (14) | 0.0019 (16) | 0.0022 (17) |
N4 | 0.0414 (19) | 0.0379 (18) | 0.075 (3) | −0.0029 (15) | −0.0123 (17) | 0.0051 (18) |
O2 | 0.113 (3) | 0.0430 (17) | 0.072 (2) | −0.0017 (16) | 0.010 (2) | −0.0044 (15) |
O3 | 0.119 (3) | 0.0353 (16) | 0.103 (3) | 0.0007 (17) | −0.026 (2) | 0.0073 (17) |
O4 | 0.0609 (19) | 0.0433 (15) | 0.079 (2) | 0.0103 (14) | 0.0043 (15) | −0.0019 (14) |
O5 | 0.095 (3) | 0.140 (3) | 0.047 (2) | 0.007 (2) | 0.0077 (19) | −0.007 (2) |
O6 | 0.067 (2) | 0.0597 (18) | 0.072 (2) | −0.0003 (15) | 0.0160 (17) | 0.0087 (16) |
O1 | 0.097 (3) | 0.0328 (15) | 0.099 (3) | −0.0081 (15) | 0.007 (2) | 0.0106 (16) |
C1 | 0.068 (3) | 0.065 (3) | 0.058 (3) | −0.006 (2) | 0.012 (2) | 0.015 (2) |
C2 | 0.063 (3) | 0.060 (3) | 0.042 (2) | 0.008 (2) | 0.0049 (19) | −0.007 (2) |
C3 | 0.084 (4) | 0.051 (2) | 0.048 (3) | 0.013 (2) | 0.006 (2) | 0.010 (2) |
C4 | 0.073 (3) | 0.036 (2) | 0.053 (3) | −0.0020 (19) | 0.007 (2) | 0.0068 (18) |
C5 | 0.062 (3) | 0.0344 (18) | 0.038 (2) | 0.0014 (17) | 0.0056 (18) | −0.0034 (16) |
C6 | 0.070 (3) | 0.052 (2) | 0.050 (2) | −0.002 (2) | 0.004 (2) | 0.0139 (19) |
C7 | 0.047 (2) | 0.047 (2) | 0.044 (2) | 0.0037 (18) | 0.0029 (17) | −0.0105 (18) |
C8 | 0.054 (3) | 0.070 (3) | 0.066 (3) | 0.013 (2) | 0.002 (2) | 0.007 (2) |
C9 | 0.042 (3) | 0.118 (4) | 0.071 (3) | 0.004 (3) | −0.005 (2) | 0.013 (3) |
C10 | 0.060 (3) | 0.078 (3) | 0.056 (3) | −0.013 (2) | 0.014 (2) | −0.007 (2) |
C11 | 0.063 (3) | 0.066 (3) | 0.054 (3) | −0.002 (2) | 0.008 (2) | 0.007 (2) |
C12 | 0.048 (2) | 0.065 (3) | 0.053 (3) | 0.009 (2) | −0.005 (2) | −0.001 (2) |
Br1 | 0.0635 (4) | 0.1164 (5) | 0.0676 (4) | 0.0127 (3) | 0.0060 (3) | −0.0013 (3) |
Br2 | 0.0876 (5) | 0.1390 (6) | 0.0825 (5) | −0.0422 (4) | 0.0262 (3) | 0.0036 (3) |
N1—C5 | 1.456 (5) | C2—Br1 | 1.895 (5) |
N1—H10 | 0.89 | C3—C4 | 1.369 (6) |
N1—H9 | 0.89 | C3—H2 | 0.93 |
N1—H11 | 0.89 | C4—C5 | 1.375 (5) |
N2—C7 | 1.465 (5) | C4—H3 | 0.93 |
N2—H14 | 0.89 | C5—C6 | 1.373 (6) |
N2—H13 | 0.89 | C6—H4 | 0.93 |
N2—H12 | 0.89 | C7—C12 | 1.364 (6) |
N3—O5 | 1.207 (5) | C7—C8 | 1.370 (6) |
N3—O3 | 1.245 (4) | C8—C9 | 1.379 (7) |
N3—O2 | 1.249 (4) | C8—H5 | 0.93 |
N4—O1 | 1.229 (4) | C9—C10 | 1.360 (7) |
N4—O4 | 1.254 (4) | C9—H6 | 0.93 |
N4—O6 | 1.258 (4) | C10—C11 | 1.366 (6) |
C1—C6 | 1.378 (7) | C10—Br2 | 1.900 (4) |
C1—C2 | 1.382 (6) | C11—C12 | 1.372 (6) |
C1—H1 | 0.93 | C11—H7 | 0.93 |
C2—C3 | 1.369 (6) | C12—H8 | 0.93 |
C5—N1—H10 | 109.5 | C3—C4—C5 | 119.7 (4) |
C5—N1—H9 | 109.5 | C3—C4—H3 | 120.2 |
H10—N1—H9 | 109.5 | C5—C4—H3 | 120.2 |
C5—N1—H11 | 109.5 | C6—C5—C4 | 120.7 (4) |
H10—N1—H11 | 109.5 | C6—C5—N1 | 119.5 (3) |
H9—N1—H11 | 109.5 | C4—C5—N1 | 119.8 (4) |
C7—N2—H14 | 109.5 | C5—C6—C1 | 119.4 (4) |
C7—N2—H13 | 109.5 | C5—C6—H4 | 120.3 |
H14—N2—H13 | 109.5 | C1—C6—H4 | 120.3 |
C7—N2—H12 | 109.5 | C12—C7—C8 | 121.2 (4) |
H14—N2—H12 | 109.5 | C12—C7—N2 | 118.9 (4) |
H13—N2—H12 | 109.5 | C8—C7—N2 | 119.9 (4) |
O5—N3—O3 | 123.7 (4) | C7—C8—C9 | 119.5 (4) |
O5—N3—O2 | 121.3 (4) | C7—C8—H5 | 120.3 |
O3—N3—O2 | 115.0 (4) | C9—C8—H5 | 120.3 |
O1—N4—O4 | 119.8 (4) | C10—C9—C8 | 119.0 (4) |
O1—N4—O6 | 120.9 (4) | C10—C9—H6 | 120.5 |
O4—N4—O6 | 119.3 (3) | C8—C9—H6 | 120.5 |
C6—C1—C2 | 119.8 (4) | C9—C10—C11 | 121.5 (4) |
C6—C1—H1 | 120.1 | C9—C10—Br2 | 120.0 (4) |
C2—C1—H1 | 120.1 | C11—C10—Br2 | 118.5 (4) |
C3—C2—C1 | 120.1 (5) | C10—C11—C12 | 119.6 (4) |
C3—C2—Br1 | 120.0 (3) | C10—C11—H7 | 120.2 |
C1—C2—Br1 | 119.9 (4) | C12—C11—H7 | 120.2 |
C2—C3—C4 | 120.3 (4) | C7—C12—C11 | 119.2 (4) |
C2—C3—H2 | 119.9 | C7—C12—H8 | 120.4 |
C4—C3—H2 | 119.9 | C11—C12—H8 | 120.4 |
C6—C1—C2—C3 | −0.4 (7) | C12—C7—C8—C9 | 1.2 (7) |
C6—C1—C2—Br1 | 178.7 (3) | N2—C7—C8—C9 | 179.8 (4) |
C1—C2—C3—C4 | 0.4 (6) | C7—C8—C9—C10 | 0.2 (7) |
Br1—C2—C3—C4 | −178.7 (3) | C8—C9—C10—C11 | −1.1 (8) |
C2—C3—C4—C5 | −0.6 (6) | C8—C9—C10—Br2 | 178.5 (4) |
C3—C4—C5—C6 | 0.7 (6) | C9—C10—C11—C12 | 0.6 (7) |
C3—C4—C5—N1 | 179.2 (3) | Br2—C10—C11—C12 | −179.1 (3) |
C4—C5—C6—C1 | −0.6 (6) | C8—C7—C12—C11 | −1.8 (6) |
N1—C5—C6—C1 | −179.2 (4) | N2—C7—C12—C11 | 179.6 (4) |
C2—C1—C6—C5 | 0.4 (7) | C10—C11—C12—C7 | 0.9 (6) |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H9···O2i | 0.89 | 2.19 | 2.930 (5) | 140 |
N1—H9···O3i | 0.89 | 2.15 | 3.002 (5) | 160 |
N1—H10···O4i | 0.89 | 2.08 | 2.957 (4) | 167 |
N1—H11···O2ii | 0.89 | 1.91 | 2.773 (4) | 162 |
N2—H12···O1i | 0.89 | 2.59 | 3.356 (6) | 145 |
N2—H12···O6i | 0.89 | 2.11 | 2.827 (5) | 137 |
N2—H12···O1iii | 0.89 | 2.59 | 3.158 (5) | 122 |
N2—H13···O3iv | 0.89 | 2.12 | 2.774 (5) | 130 |
N2—H13···O6iv | 0.89 | 2.55 | 3.345 (5) | 149 |
N2—H14···O4iii | 0.89 | 2.19 | 2.831 (5) | 129 |
C4—H3···O1iii | 0.93 | 2.41 | 3.129 (5) | 134 |
C12—H8···O3i | 0.93 | 2.59 | 3.410 (5) | 147 |
C12—H8···O6i | 0.93 | 2.58 | 3.1943 (3) | 124 |
Symmetry codes: (i) x+1, y, z; (ii) x+1, −y+1/2, z−1/2; (iii) −x+1, −y+1, −z; (iv) −x+1, −y+1, −z+1. |
Funding information
RA gratefully acknowledges Periyar University for providing financial support under the University Research Fellowship (URF) scheme.
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