Crystal structure and Hirshfeld surface analysis of 3-amino-5-phenyl­thia­zolidin-2-iminium bromide

In the crystal of the title salt, the cations and anions are linked via N—H⋯Br hydrogen bonds to form a three-dimensional network.

Abstract

In the cation of the title salt, C₉H₁₂N₃S⁺·Br⁻, the thia­zolidine ring adopts an envelope conformation with the C atom adjacent to the phenyl ring as the flap. In the crystal, N—H⋯Br hydrogen bonds link the components into a three-dimensional network. Weak π–π stacking inter­actions between the phenyl rings of adjacent cations also contribute to the mol­ecular packing. A Hirshfeld surface analysis was conducted to qu­antify the contributions of the different inter­molecular inter­actions and contacts.

Chemical context  

As well as their synthetic utility, thia­zolidine derivatives possess a broad spectrum of biological activities such as anti­malarial, anti­bacterial, anti­microbial, anti-inflammatory, anti­cancer, etc. The biological activities of compounds containing a thia­zolidine core, such as 1,3-thia­zolidines, 2,4-dione-, 4-oxo-thia­zolidine, etc. were summarized in a recent review (Makwana & Malani, 2017 ▸). On the other hand, as hydrazones these N-containing ligands have been widely used in the synthesis of coordination compounds (Gurbanov et al., 2018a ▸,b ▸). The non-covalent donor or acceptor properties of N-containing ligands can also contribute to their catalytic activity, among other properties (Mahmudov et al., 2019 ▸; Zubkov et al., 2018 ▸). As part of our ongoing work in this area, we now describe the synthesis and structure of the title mol­ecular salt, C₉H₁₂N₃S⁺·Br⁻, (I).

Structural commentary  

In the cation of (I) (Fig. 1 ▸), the thia­zolidine ring (S1/N1/C1–C3) adopts an envelope conformation with puckering parameters of Q(2) = 0.317 (2) Å and φ(2) = 225.2 (4)°: the flap atom is C1. In the arbitrarily chosen asymmetric unit, C1 has an R configuration, but symmetry generates a racemic mixture in the crystal. The dihedral angle between the mean plane of the thia­zolidine ring (all atoms) and the phenyl ring (C4–C9) is 89.27 (13)°.

Figure 1.

The mol­ecular structure of the title salt. Displacement ellipsoids are drawn at the 50% probability level and the H⋯Br hydrogen bond is indicated by a dashed line.

Supra­molecular features and Hirshfeld surface analysis  

In the crystal, each cation forms N—H⋯Br hydrogen bonds (Table 1 ▸) as well as aromatic π–π stacking inter­actions between the phenyl rings of adjacent cations [Cg2⋯Cg2^iv = 3.7758 (16) Å; symmetry code: (iv) 1 − x, 1 − y, 2 − z; where Cg2 is the centroid of the phenyl ring of the cation]: chains of cations form along the [101] direction (Fig. 2 ▸). Taking into account the hydrogen bonding and π-π stacking, the overall connectivity is three-dimensional.

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N2—H2A⋯Br1i	0.90	2.68	3.530 (2)	158
N2—H2B⋯Br1ii	0.90	2.73	3.524 (2)	148
N3—H3A⋯Br1	0.90	2.38	3.271 (2)	169
N3—H3B⋯Br1iii	0.90	2.56	3.337 (2)	145

Symmetry codes: (i) ; (ii) ; (iii) .

Figure 2.

Part of the crystal structure of the title compound, showing the formation of N—H⋯Br hydrogen bonds in the ac plane.

Hirshfeld surface analysis (Spackman & Jayatilaka, 2009 ▸; Spackman & McKinnon, 2002 ▸) was carried out with CrystalExplorer3.1 (Wolff et al., 2012 ▸) to further investigate the presence of hydrogen bonds and inter­molecular inter­actions in the crystal structure (see supporting information). Fig. 3 ▸(a) shows the two-dimensional fingerprint of the sum of the contacts contributing to the Hirshfeld surface represented in normal mode while those delineated into H⋯H (41.5%), Br⋯N/N⋯Br (24.1%), C⋯H/H⋯C (13.8%) and S⋯H/H⋯S (11.7%) contacts, respectively, are shown in Fig. 3 ▸ b–e. All contacts are listed in Table 2 ▸.

Figure 3.

The two-dimensional fingerprint plots of the title salt, showing (a) all inter­actions, and delineated into (b) H⋯H, (c) Br⋯N/N⋯Br, (d) C⋯H/H⋯C and (e) S⋯H/H⋯S inter­actions [d _e and d _i represent the distances from a point on the Hirshfeld surface to the nearest atoms outside (external) and inside (inter­nal) the surface, respectively].

Table 2. Percentage contributions of inter­atomic contacts to the Hirshfeld surface for the title salt.

Contact	Percentage contribution
H⋯H	41.5
Br⋯N/N⋯Br	24.1
C⋯H/H⋯C	13.8
S⋯H/H⋯S	11.7
N⋯H/H⋯N	3.6
C⋯C	3.3
N⋯C/C⋯N	1.5
N⋯N	0.3
S⋯C/C⋯S	0.3

Database survey  

A search of the Cambridge Structural Database (CSD, Version 5.40, February 2019; Groom et al., 2016 ▸) for 2-thia­zolidiniminium compounds gave eight hits, viz. BOBWIB (Khalilov et al., 2019 ▸), UDELUN (Akkurt et al., 2018 ▸), WILBIC (Marthi et al., 1994 ▸), WILBOI (Marthi et al., 1994 ▸), WILBOI01 (Marthi et al., 1994 ▸), YITCEJ (Martem’yanova et al., 1993a ▸), YITCAF (Martem’yanova et al., 1993b ▸) and YOPLUK (Marthi et al., 1995 ▸).

In the crystal of BOBWIB (Khalilov et al., 2019 ▸), the thia­zolidine ring adopts an envelope conformation. In the crystal, centrosymmetrically related cations and anions are linked into dimeric units via N—H⋯Br hydrogen bonds, which are further connected by weak C—H⋯Br hydrogen bonds into chains parallel to [110]. In the crystal of UDELUN (Akkurt et al., 2018 ▸), C—H⋯Br and N—H⋯Br hydrogen bonds link the components into a three-dimensional network with the cations and anions stacked along the b-axis direction. Weak C—H⋯π inter­actions, which only involve the minor disorder component of the ring, also contribute to the mol­ecular packing. In addition, there are also inversion-related Cl⋯Cl halogen bonds and C—Cl⋯π(ring) contacts. In the other structures, the 3-N atom carries a C substituent: the first three crystal structures were determined for racemic (WILBIC; Marthi et al., 1994 ▸) and two optically active samples (WILBOI and WILBOI01; Marthi et al., 1994 ▸) of 3-(2′-chloro-2′-phenyl­eth­yl)-2-thia­zolidiniminium p-toluene­sulfonate. In all three structures, the most disordered fragment of these mol­ecules is the asymmetric C atom and the Cl atom attached to it. The disorder of the cation in the racemate corresponds to the presence of both enanti­omers at each site in the ratio 0.821 (3): 0.179 (3). The system of hydrogen bonds connecting two cations and two anions into 12-membered rings is identical in the racemic and in the optically active crystals. YITCEJ (Martem’yanova et al., 1993a ▸) is a product of the inter­action of 2-amino-5-methyl­thia­zoline with methyl iodide, with alkyl­ation at the endocylic nitro­gen atom, while YITCAF (Martem’yanova et al., 1993b ▸) is a product of the reaction of 3-nitro-5-meth­oxy-, 3-nitro-5-chloro-, and 3-bromo-5-nitro­salicyl­aldehyde with the heterocyclic base to form the salt-like complexes.

Synthesis and crystallization  

To a solution of 2.2 mmol (0.6 g) (1,2-di­bromo­eth­yl)benzene in 20 ml of ethanol were added 2.3 mmol (0.3 g) of thio­semicarbazide hydro­chloride; 3-4 drops of piperidine were added and the mixture was refluxed for 7 h. The reaction mixture was cooled to room temperature and the solid product was precipitated from solution, collected by filtration and recrystallized from ethanol solution to give colourless crystals of (I) with a yield of 88%, m.p. = 468 K. Analysis calculated for C₉H₁₂BrN₃S: C 39.43; H 4.41; N 15.33. Found: C 39.40; H 4.39; N 15.30%. ¹H NMR (300 MHz, DMSO-d ₆) : 4.16 (q, 1H, CH₂,³ J _H–H = 5.4); 4.45 (t, 1H, CH₂, ³ J _H–H = 8.4); 5.25 (t, 1H, CH-Ar, ³ J _H–H = 5.4); 7.32–7.50 (m, 5H, 5Ar-H); 9.12 (s, 2H, NH₂); 9,78 (s, 1H, NH=). ¹³C NMR (75 MHz, DMSO-d ₆ ): 44.42, 62.06, 127.59, 128.76, 129.17, 138.85, 168.53. MS (ESI), m/z: 194.28 [C₉H₁₂N₃S]⁺ and 79.88 Br⁻.

Refinement  

Crystal data, data collection and structure refinement details are summarized in Table 3 ▸. All H atoms on C atoms were placed at calculated positions (C—H = 0.95–1.00 Å) and refined using a riding model. The N-bound hydrogen atoms were located from difference-Fourier maps and relocated to idealized locations (N—H = 0.90 Å) and refined as riding atoms. The constraint U _iso(H) = 1.2U _eq(carrier) was applied in all cases. One outlier (01) was omitted in the final cycles of refinement.

Table 3. Experimental details.

Crystal data
Chemical formula	C9H12N3S+·Br−
M r	274.19
Crystal system, space group	Monoclinic, P21/n
Temperature (K)	150
a, b, c (Å)	10.5986 (5), 8.7168 (3), 13.0308 (5)
β (°)	111.513 (2)
V (Å3)	1119.99 (8)
Z	4
Radiation type	Mo Kα
μ (mm−1)	3.82
Crystal size (mm)	0.18 × 0.14 × 0.11
Data collection
Diffractometer	Bruker APEXII CCD
Absorption correction	Multi-scan (SADABS; Bruker, 2003 ▸)
T min, T max	0.534, 0.661
No. of measured, independent and observed [I > 2σ(I)] reflections	8461, 2303, 1998
R int	0.029
(sin θ/λ)max (Å−1)	0.626
Refinement
R[F 2 > 2σ(F 2)], wR(F 2), S	0.027, 0.070, 1.02
No. of reflections	2303
No. of parameters	127
H-atom treatment	H-atom parameters constrained
Δρmax, Δρmin (e Å−3)	0.61, −0.33

Computer programs: APEX2 and SAINT (Bruker, 2003 ▸), SHELXT2014 (Sheldrick, 2015a ▸), SHELXL2016 (Sheldrick, 2015b ▸), ORTEP-3 for Windows (Farrugia, 2012 ▸) and PLATON (Spek, 2003 ▸).

Supplementary Material

CCDC reference: 1955268

Additional supporting information: crystallographic information; 3D view; checkCIF report

supplementary crystallographic information

Crystal data

C9H12N3S+·Br−	F(000) = 552
Mr = 274.19	Dx = 1.626 Mg m−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
a = 10.5986 (5) Å	Cell parameters from 3357 reflections
b = 8.7168 (3) Å	θ = 2.9–26.3°
c = 13.0308 (5) Å	µ = 3.82 mm−1
β = 111.513 (2)°	T = 150 K
V = 1119.99 (8) Å3	Block, colorless
Z = 4	0.18 × 0.14 × 0.11 mm

Data collection

Bruker APEXII CCD diffractometer	1998 reflections with I > 2σ(I)
φ and ω scans	Rint = 0.029
Absorption correction: multi-scan (SADABS; Bruker, 2003)	θmax = 26.4°, θmin = 2.9°
Tmin = 0.534, Tmax = 0.661	h = −13→13
8461 measured reflections	k = −10→10
2303 independent reflections	l = −16→16

Refinement

Refinement on F2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.027	Hydrogen site location: mixed
wR(F2) = 0.070	H-atom parameters constrained
S = 1.02	w = 1/[σ2(Fo2) + (0.0381P)2 + 0.5896P] where P = (Fo2 + 2Fc2)/3
2303 reflections	(Δ/σ)max = 0.001
127 parameters	Δρmax = 0.61 e Å−3
0 restraints	Δρmin = −0.33 e Å−3

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
Br1	0.14662 (3)	0.38142 (3)	0.26547 (2)	0.02369 (10)
S1	0.31116 (7)	0.46985 (7)	0.58677 (5)	0.02034 (15)
N1	0.4802 (2)	0.6893 (2)	0.61070 (15)	0.0159 (4)
N2	0.5487 (2)	0.8083 (2)	0.57955 (15)	0.0183 (4)
H2A	0.635551	0.776693	0.607350	0.022*
H2B	0.535901	0.891753	0.615230	0.022*
N3	0.3577 (2)	0.6293 (2)	0.42850 (16)	0.0179 (4)
H3A	0.292719	0.572157	0.379225	0.021*
H3B	0.390509	0.709317	0.402415	0.021*
C1	0.4372 (3)	0.5007 (3)	0.72776 (19)	0.0214 (5)
H1A	0.513995	0.427032	0.741377	0.026*
C2	0.4890 (3)	0.6645 (3)	0.72463 (19)	0.0189 (5)
H2C	0.432008	0.739798	0.744749	0.023*
H2D	0.583832	0.675080	0.776759	0.023*
C3	0.3879 (2)	0.6085 (3)	0.53385 (19)	0.0154 (5)
C4	0.3746 (2)	0.4760 (3)	0.81375 (18)	0.0168 (5)
C5	0.4280 (3)	0.3584 (3)	0.8912 (2)	0.0212 (5)
H5A	0.497585	0.293462	0.886358	0.025*
C6	0.3773 (3)	0.3379 (3)	0.97571 (19)	0.0208 (5)
H6A	0.412191	0.258553	1.028582	0.025*
C7	0.2769 (3)	0.4330 (3)	0.9816 (2)	0.0225 (5)
H7A	0.244208	0.420521	1.039905	0.027*
C8	0.2230 (3)	0.5463 (3)	0.9041 (2)	0.0265 (6)
H8A	0.152610	0.610477	0.908407	0.032*
C9	0.2715 (3)	0.5662 (3)	0.8203 (2)	0.0249 (6)
H9A	0.233208	0.643424	0.766388	0.030*

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
Br1	0.02460 (15)	0.02084 (15)	0.02181 (15)	−0.00181 (11)	0.00401 (11)	−0.00181 (10)
S1	0.0263 (3)	0.0175 (3)	0.0173 (3)	−0.0062 (3)	0.0081 (2)	−0.0012 (2)
N1	0.0197 (10)	0.0165 (10)	0.0132 (9)	−0.0036 (8)	0.0078 (8)	−0.0004 (8)
N2	0.0208 (11)	0.0162 (10)	0.0198 (10)	−0.0030 (9)	0.0099 (9)	−0.0004 (8)
N3	0.0239 (11)	0.0151 (10)	0.0144 (10)	−0.0011 (9)	0.0066 (8)	−0.0014 (8)
C1	0.0215 (13)	0.0233 (13)	0.0184 (12)	0.0033 (11)	0.0061 (10)	0.0023 (10)
C2	0.0225 (13)	0.0215 (12)	0.0126 (11)	−0.0041 (10)	0.0064 (10)	−0.0018 (10)
C3	0.0176 (12)	0.0121 (11)	0.0178 (12)	0.0027 (9)	0.0082 (10)	−0.0009 (9)
C4	0.0171 (12)	0.0193 (12)	0.0131 (11)	−0.0054 (10)	0.0046 (9)	−0.0010 (9)
C5	0.0175 (12)	0.0183 (12)	0.0255 (13)	−0.0020 (10)	0.0051 (10)	−0.0066 (10)
C6	0.0244 (13)	0.0193 (12)	0.0147 (12)	−0.0050 (10)	0.0027 (10)	0.0016 (10)
C7	0.0215 (13)	0.0253 (13)	0.0214 (13)	−0.0100 (11)	0.0085 (11)	−0.0029 (11)
C8	0.0208 (13)	0.0258 (14)	0.0335 (15)	−0.0012 (11)	0.0108 (12)	−0.0007 (12)
C9	0.0219 (13)	0.0246 (13)	0.0266 (14)	0.0041 (11)	0.0070 (11)	0.0036 (11)

Geometric parameters (Å, º)

S1—C3	1.735 (2)	C2—H2C	0.9900
S1—C1	1.853 (2)	C2—H2D	0.9900
N1—C3	1.318 (3)	C4—C9	1.374 (4)
N1—N2	1.408 (3)	C4—C5	1.404 (3)
N1—C2	1.469 (3)	C5—C6	1.403 (4)
N2—H2A	0.9000	C5—H5A	0.9500
N2—H2B	0.9000	C6—C7	1.373 (4)
N3—C3	1.303 (3)	C6—H6A	0.9500
N3—H3A	0.9000	C7—C8	1.378 (4)
N3—H3B	0.9000	C7—H7A	0.9500
C1—C4	1.513 (3)	C8—C9	1.378 (4)
C1—C2	1.535 (4)	C8—H8A	0.9500
C1—H1A	1.0000	C9—H9A	0.9500
C3—S1—C1	91.16 (11)	N3—C3—N1	123.6 (2)
C3—N1—N2	119.48 (18)	N3—C3—S1	123.08 (18)
C3—N1—C2	116.3 (2)	N1—C3—S1	113.33 (17)
N2—N1—C2	123.48 (18)	C9—C4—C5	119.6 (2)
N1—N2—H2A	102.6	C9—C4—C1	122.7 (2)
N1—N2—H2B	104.8	C5—C4—C1	117.7 (2)
H2A—N2—H2B	111.4	C6—C5—C4	119.2 (2)
C3—N3—H3A	120.2	C6—C5—H5A	120.4
C3—N3—H3B	121.7	C4—C5—H5A	120.4
H3A—N3—H3B	117.4	C7—C6—C5	119.6 (2)
C4—C1—C2	114.2 (2)	C7—C6—H6A	120.2
C4—C1—S1	111.16 (17)	C5—C6—H6A	120.2
C2—C1—S1	104.09 (16)	C6—C7—C8	120.9 (2)
C4—C1—H1A	109.1	C6—C7—H7A	119.5
C2—C1—H1A	109.1	C8—C7—H7A	119.5
S1—C1—H1A	109.1	C9—C8—C7	119.7 (3)
N1—C2—C1	105.85 (19)	C9—C8—H8A	120.1
N1—C2—H2C	110.6	C7—C8—H8A	120.1
C1—C2—H2C	110.6	C4—C9—C8	120.9 (2)
N1—C2—H2D	110.6	C4—C9—H9A	119.5
C1—C2—H2D	110.6	C8—C9—H9A	119.5
H2C—C2—H2D	108.7
C3—S1—C1—C4	147.17 (19)	C2—C1—C4—C9	53.9 (3)
C3—S1—C1—C2	23.78 (17)	S1—C1—C4—C9	−63.5 (3)
C3—N1—C2—C1	26.7 (3)	C2—C1—C4—C5	−124.2 (2)
N2—N1—C2—C1	−163.3 (2)	S1—C1—C4—C5	118.4 (2)
C4—C1—C2—N1	−152.1 (2)	C9—C4—C5—C6	−1.7 (4)
S1—C1—C2—N1	−30.7 (2)	C1—C4—C5—C6	176.5 (2)
N2—N1—C3—N3	1.9 (3)	C4—C5—C6—C7	−0.2 (4)
C2—N1—C3—N3	172.3 (2)	C5—C6—C7—C8	1.5 (4)
N2—N1—C3—S1	−178.62 (16)	C6—C7—C8—C9	−0.9 (4)
C2—N1—C3—S1	−8.2 (3)	C5—C4—C9—C8	2.2 (4)
C1—S1—C3—N3	169.2 (2)	C1—C4—C9—C8	−175.8 (2)
C1—S1—C3—N1	−10.29 (19)	C7—C8—C9—C4	−1.0 (4)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2A···Br1i	0.90	2.68	3.530 (2)	158
N2—H2B···Br1ii	0.90	2.73	3.524 (2)	148
N3—H3A···Br1	0.90	2.38	3.271 (2)	169
N3—H3B···Br1iii	0.90	2.56	3.337 (2)	145

Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) x+1/2, −y+3/2, z+1/2; (iii) −x+1/2, y+1/2, −z+1/2.

Funding Statement

This work was funded by Baku State University grant 50 + 50 to A. N. Khalilov.