4-(o-Tol­yl)piperazin-1-ium chloride

Fun, H.-K.; Asik, S.I.J.; Chandrakantha, B.; Isloor, A.M.; Shetty, P.

doi:10.1107/S1600536811044394

organic compounds

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ISSN: 2056-9890

Volume 67| Part 11| November 2011| Page o3115

doi:10.1107/S1600536811044394

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4-(o-Tolyl)piperazin-1-ium chloride

Hoong-Kun Fun,^a ^*‡ Safra Izuani Jama Asik,^a B. Chandrakantha,^b Arun M. Isloor ^c and Prakash Shetty ^d

^aX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia, ^bDepartment of Chemistry, Manipal Institute of Technology, Manipal 576 104, India., ^cMedicinal Chemistry Division, Department of Chemistry, National Institute of Technology-Karnataka, Surathkal, Mangalore, 575 025, India., and ^dDepartment of Printing, Manipal Institute of Technology, Manipal 576 104, India
^*Correspondence e-mail: hkfun@usm.my

(Received 24 October 2011; accepted 25 October 2011; online 29 October 2011)

In the title molecular salt, C₁₁H₁₇N₂⁺·Cl⁻, the piperazin-1-ium ring adopts a chair conformation with the aromatic ring in a pseudo-equatorial orientation. The dihedral angle between the benzene ring and the mean plane of the piperazin-1-ium ring is 51.22 (6)°. In the crystal, N—H⋯Cl hydrogen bonds link the molecules into chains propagating in [100]. Weak C—H⋯π interactions also ocur.

Related literature

For the medicinal applications of piperazine derivatives, see: Amir et al. (2004 ); Omar & AboulWafa (1986 ); El-Emam et al. (2004 ). For conformational analysis, see: Cremer & Pople (1975 ). For a related structure, see: Ben Gharbia et al. (2008 ).

Experimental

Crystal data

C₁₁H₁₇N₂⁺·Cl⁻
M_r = 212.72
Orthorhombic, P 2₁ 2₁ 2₁
a = 8.1572 (2) Å
b = 11.2821 (3) Å
c = 12.4256 (3) Å
V = 1143.53 (5) Å³
Z = 4
Mo Kα radiation
μ = 0.30 mm⁻¹
T = 296 K
0.54 × 0.33 × 0.23 mm

Data collection

Bruker APEX DUO CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2009) T_min = 0.854, T_max = 0.936
8246 measured reflections
4871 independent reflections
4172 reflections with I > 2σ(I)
R_int = 0.016

Refinement

R[F² > 2σ(F²)] = 0.032
wR(F²) = 0.092
S = 0.95
4871 reflections
128 parameters
H-atom parameters constrained
Δρ_max = 0.23 e Å⁻³
Δρ_min = −0.19 e Å⁻³
Absolute structure: Flack (1983 ), 1943 Friedel pairs
Flack parameter: 0.02 (4)

Table 1
Hydrogen-bond geometry (Å, °)

Cg2 is the centroid of C5–C10 ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1N1⋯Cl1ⁱ	0.87	2.26	3.1155 (10)	167
N1—H2N1⋯Cl1ⁱⁱ	0.87	2.23	3.0956 (10)	177
C3—H3A⋯Cg2ⁱⁱⁱ	0.97	2.79	3.5342 (11)	134
Symmetry codes: (i) x+1, y+1, z+1; (ii) $[x+{\script{1\over 2}}, -y+{\script{3\over 2}}, -z+1]$ ; (iii) $[-x+{\script{3\over 2}}, -y+2, z+{\script{1\over 2}}]$ .

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536811044394/hb6474sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811044394/hb6474Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536811044394/hb6474Isup3.cml

checkCIF report

Comment top

During the past years considerable evidence has been accumulated to demonstrate the efficacy of piperazine derivatives possessing antibacterial and antimicrobial activities (Amir et al., 2004). For instance, Linezolid, Eperezolid, which are currently important antibiotics used for the treatment of microbial infections, contain the piperazine and morpholine ring in their structures (Omar & AboulWafa, 1986, El-Emam et al., 2004).

As shown in Fig. 1, the asymmetric unit of the title compound contains a 4-(o-tolyl)piperazin-1-ium cation and a chloride anion. The benzene (C5–C10) ring and the mean plane of 4-(o-tolyl) piperazin-1-ium (C1–C4) make a dihedral angle of 51.22 (6)°. The piperazin-1-ium (N1/N2/C1–C4) adopts a chair conformation with puckering parameters Q = 0.5859 (11) Å, θ = 173.86 (11)° and ϕ = 3.0 (11)° (Cremer & Pople, 1975). It is also noted that the geometric parameters [d_a_v(C–N) = 1.4653 (13) Å and d_a_v (C–C) = 1.5082 (16) Å for the 4-(o-tolyl)piperazin-1-ium moeity are in close agreement with those found in 4-(2,3-dimethylphenyl)piperazin-1-ium chloride monohydrate (Ben Gharbia et al., 2008).

In the crystal (Fig. 2), N1—H1N1···Cl1 and N1—H2N1···Cl1 hydrogen bonds (Table 1) link the molecules into chains along the a axis. In addition, the crystal packing features weak intermolecular C—H···π interactions involving the benzene (C5–C10 ; centroid Cg2) ring with a distance of 3.5342 (11) Å.

Related literature top

For the medicinal applications of piperazine derivatives, see: Amir et al. (2004); Omar & AboulWafa (1986); El-Emam et al. (2004). For conformational analysis, see: Cremer & Pople (1975). For a related structure, see: Ben Gharbia et al. (2008).

Experimental top

To a stirred solution of 2-flurotoluene (2g, 0.0181 mol) and anhydrous potassium carbonate (3.7g, 0.027 mol) in dry acetonitrile (20 ml), piperizine-1-carboxylic acid tert butyl ester (3.38g, 0.0181 mol) was added dropwise at RT and reaction mixture was stirred at RT for 5h. After the completion of reaction, the reaction mixture was filtered and the filtrate was concentrated. The product (5g) was then dissolved with HCl in dioxane (25 ml) and stirred at RT for 2 h. The reaction mixture was concentrated through high vacuum. The crude product was recrystallised from hot ethanol to afford title compound as colourless blocks (3.0g, 66%). M.p > 620K.

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top

	Fig. 1. The structure of the title compound, showing 50% probability displacement ellipsoids.
	Fig. 2. The crystal packing, viewed along the c axis, showing one-dimensional chains along the a axis. Hydrogen atoms that not involved in hydrogen bonding (dashed lines) are omitted for clarity.

4-(o-Tolyl)piperazin-1-ium chloride top

Crystal data top

C₁₁H₁₇N₂⁺·Cl⁻	F(000) = 456
M_r = 212.72	D_x = 1.236 Mg m⁻³
Orthorhombic, P2₁2₁2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 3871 reflections
a = 8.1572 (2) Å	θ = 2.4–35.1°
b = 11.2821 (3) Å	µ = 0.30 mm⁻¹
c = 12.4256 (3) Å	T = 296 K
V = 1143.53 (5) Å³	Block, colourless
Z = 4	0.54 × 0.33 × 0.23 mm

Data collection top

Bruker APEX DUO CCD diffractometer	4871 independent reflections
Radiation source: fine-focus sealed tube	4172 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.016
ϕ and ω scans	θ_max = 35.5°, θ_min = 2.4°
Absorption correction: multi-scan (SADABS; Bruker, 2009)	h = −7→13
T_min = 0.854, T_max = 0.936	k = −10→18
8246 measured reflections	l = −6→20

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.032	H-atom parameters constrained
wR(F²) = 0.092	w = 1/[σ²(F_o²) + (0.0554P)² + 0.0493P] where P = (F_o² + 2F_c²)/3
S = 0.95	(Δ/σ)_max < 0.001
4871 reflections	Δρ_max = 0.23 e Å⁻³
128 parameters	Δρ_min = −0.19 e Å⁻³
0 restraints	Absolute structure: Flack (1983), 1943 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.02 (4)

Crystal data top

C₁₁H₁₇N₂⁺·Cl⁻	V = 1143.53 (5) Å³
M_r = 212.72	Z = 4
Orthorhombic, P2₁2₁2₁	Mo Kα radiation
a = 8.1572 (2) Å	µ = 0.30 mm⁻¹
b = 11.2821 (3) Å	T = 296 K
c = 12.4256 (3) Å	0.54 × 0.33 × 0.23 mm

Data collection top

Bruker APEX DUO CCD diffractometer	4871 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2009)	4172 reflections with I > 2σ(I)
T_min = 0.854, T_max = 0.936	R_int = 0.016
8246 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.032	H-atom parameters constrained
wR(F²) = 0.092	Δρ_max = 0.23 e Å⁻³
S = 0.95	Δρ_min = −0.19 e Å⁻³
4871 reflections	Absolute structure: Flack (1983), 1943 Friedel pairs
128 parameters	Absolute structure parameter: 0.02 (4)
0 restraints

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.

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > 2sigma(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Cl1	0.37470 (3)	0.15197 (3)	0.10255 (2)	0.04298 (7)
N1	1.02356 (12)	1.12619 (8)	1.00673 (8)	0.04027 (19)
H1N1	1.1142	1.1422	1.0407	0.048*
H2N1	0.9841	1.1900	0.9779	0.048*
N2	0.81569 (10)	0.94027 (7)	0.93398 (6)	0.03177 (15)
C1	0.93463 (14)	0.99338 (10)	0.86053 (8)	0.0381 (2)
H1A	0.8839	1.0581	0.8214	0.046*
H1B	0.9713	0.9347	0.8088	0.046*
C2	1.07872 (14)	1.03893 (12)	0.92397 (10)	0.0461 (2)
H2A	1.1337	0.9732	0.9590	0.055*
H2B	1.1563	1.0765	0.8757	0.055*
C3	0.89107 (15)	1.07704 (11)	1.07575 (8)	0.0427 (2)
H3A	0.8502	1.1384	1.1234	0.051*
H3B	0.9346	1.0134	1.1197	0.051*
C4	0.75240 (13)	1.03055 (10)	1.00711 (8)	0.0380 (2)
H4A	0.6679	0.9967	1.0526	0.046*
H4B	0.7042	1.0949	0.9662	0.046*
C5	0.69593 (12)	0.86761 (8)	0.88251 (6)	0.03052 (16)
C6	0.53332 (14)	0.90410 (10)	0.87004 (8)	0.0382 (2)
H6A	0.5015	0.9783	0.8951	0.046*
C7	0.41906 (15)	0.83147 (12)	0.82098 (9)	0.0468 (3)
H7A	0.3115	0.8571	0.8125	0.056*
C8	0.46538 (18)	0.72070 (12)	0.78461 (10)	0.0507 (3)
H8A	0.3895	0.6718	0.7507	0.061*
C9	0.62468 (18)	0.68295 (10)	0.79889 (9)	0.0451 (2)
H9A	0.6539	0.6076	0.7754	0.054*
C10	0.74324 (14)	0.75387 (9)	0.84727 (7)	0.03504 (18)
C11	0.91432 (17)	0.70764 (11)	0.86458 (11)	0.0482 (3)
H11A	0.9117	0.6227	0.8691	0.072*
H11B	0.9577	0.7396	0.9303	0.072*
H11C	0.9827	0.7312	0.8054	0.072*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cl1	0.03237 (11)	0.04279 (13)	0.05376 (13)	−0.00052 (10)	0.00001 (10)	0.00279 (11)
N1	0.0329 (4)	0.0355 (4)	0.0524 (5)	−0.0008 (3)	−0.0083 (3)	−0.0036 (3)
N2	0.0313 (4)	0.0318 (4)	0.0322 (3)	−0.0009 (3)	0.0029 (3)	−0.0031 (3)
C1	0.0336 (5)	0.0428 (5)	0.0377 (4)	−0.0050 (4)	0.0063 (4)	−0.0029 (4)
C2	0.0295 (4)	0.0507 (6)	0.0580 (6)	−0.0033 (4)	0.0039 (4)	−0.0098 (5)
C3	0.0469 (6)	0.0424 (5)	0.0388 (4)	−0.0020 (5)	−0.0015 (4)	−0.0088 (4)
C4	0.0343 (4)	0.0393 (5)	0.0404 (4)	−0.0028 (4)	0.0055 (4)	−0.0101 (4)
C5	0.0328 (4)	0.0306 (4)	0.0282 (3)	−0.0023 (3)	0.0012 (3)	0.0013 (3)
C6	0.0340 (4)	0.0396 (5)	0.0410 (4)	−0.0005 (4)	−0.0011 (4)	0.0005 (4)
C7	0.0363 (5)	0.0571 (7)	0.0470 (5)	−0.0074 (5)	−0.0054 (4)	0.0010 (5)
C8	0.0522 (7)	0.0509 (7)	0.0489 (5)	−0.0197 (6)	−0.0047 (5)	−0.0018 (5)
C9	0.0574 (7)	0.0347 (5)	0.0433 (5)	−0.0106 (5)	0.0040 (5)	−0.0040 (4)
C10	0.0425 (5)	0.0295 (4)	0.0331 (4)	−0.0009 (4)	0.0021 (3)	0.0016 (3)
C11	0.0518 (7)	0.0381 (5)	0.0548 (6)	0.0117 (5)	−0.0019 (5)	−0.0026 (5)

Geometric parameters (Å, º) top

N1—C3	1.4869 (15)	C4—H4B	0.9700
N1—C2	1.4930 (15)	C5—C6	1.3974 (14)
N1—H1N1	0.8702	C5—C10	1.4098 (13)
N1—H2N1	0.8662	C6—C7	1.3827 (16)
N2—C5	1.4267 (12)	C6—H6A	0.9300
N2—C4	1.4593 (12)	C7—C8	1.382 (2)
N2—C1	1.4606 (13)	C7—H7A	0.9300
C1—C2	1.5056 (16)	C8—C9	1.379 (2)
C1—H1A	0.9700	C8—H8A	0.9300
C1—H1B	0.9700	C9—C10	1.3918 (16)
C2—H2A	0.9700	C9—H9A	0.9300
C2—H2B	0.9700	C10—C11	1.5053 (17)
C3—C4	1.5107 (15)	C11—H11A	0.9600
C3—H3A	0.9700	C11—H11B	0.9600
C3—H3B	0.9700	C11—H11C	0.9600
C4—H4A	0.9700

C3—N1—C2	111.74 (9)	C3—C4—H4A	109.8
C3—N1—H1N1	114.6	N2—C4—H4B	109.8
C2—N1—H1N1	102.4	C3—C4—H4B	109.8
C3—N1—H2N1	106.2	H4A—C4—H4B	108.3
C2—N1—H2N1	112.0	C6—C5—C10	119.57 (9)
H1N1—N1—H2N1	110.1	C6—C5—N2	122.03 (9)
C5—N2—C4	115.97 (8)	C10—C5—N2	118.35 (9)
C5—N2—C1	114.24 (7)	C7—C6—C5	120.94 (11)
C4—N2—C1	109.74 (8)	C7—C6—H6A	119.5
N2—C1—C2	109.36 (9)	C5—C6—H6A	119.5
N2—C1—H1A	109.8	C6—C7—C8	119.73 (12)
C2—C1—H1A	109.8	C6—C7—H7A	120.1
N2—C1—H1B	109.8	C8—C7—H7A	120.1
C2—C1—H1B	109.8	C9—C8—C7	119.67 (11)
H1A—C1—H1B	108.3	C9—C8—H8A	120.2
N1—C2—C1	110.51 (9)	C7—C8—H8A	120.2
N1—C2—H2A	109.5	C8—C9—C10	122.20 (11)
C1—C2—H2A	109.5	C8—C9—H9A	118.9
N1—C2—H2B	109.5	C10—C9—H9A	118.9
C1—C2—H2B	109.5	C9—C10—C5	117.86 (11)
H2A—C2—H2B	108.1	C9—C10—C11	120.45 (10)
N1—C3—C4	110.37 (8)	C5—C10—C11	121.65 (10)
N1—C3—H3A	109.6	C10—C11—H11A	109.5
C4—C3—H3A	109.6	C10—C11—H11B	109.5
N1—C3—H3B	109.6	H11A—C11—H11B	109.5
C4—C3—H3B	109.6	C10—C11—H11C	109.5
H3A—C3—H3B	108.1	H11A—C11—H11C	109.5
N2—C4—C3	109.21 (9)	H11B—C11—H11C	109.5
N2—C4—H4A	109.8

C5—N2—C1—C2	−164.57 (9)	C10—C5—C6—C7	−1.76 (15)
C4—N2—C1—C2	63.23 (11)	N2—C5—C6—C7	−179.23 (10)
C3—N1—C2—C1	53.08 (13)	C5—C6—C7—C8	0.65 (17)
N2—C1—C2—N1	−57.39 (13)	C6—C7—C8—C9	0.87 (18)
C2—N1—C3—C4	−53.24 (12)	C7—C8—C9—C10	−1.31 (18)
C5—N2—C4—C3	165.32 (8)	C8—C9—C10—C5	0.20 (16)
C1—N2—C4—C3	−63.38 (11)	C8—C9—C10—C11	177.96 (11)
N1—C3—C4—N2	57.89 (12)	C6—C5—C10—C9	1.32 (13)
C4—N2—C5—C6	22.41 (12)	N2—C5—C10—C9	178.88 (9)
C1—N2—C5—C6	−106.74 (10)	C6—C5—C10—C11	−176.42 (10)
C4—N2—C5—C10	−155.10 (9)	N2—C5—C10—C11	1.14 (13)
C1—N2—C5—C10	75.76 (11)

Hydrogen-bond geometry (Å, º) top

Cg2 is the centroid of C5–C10 ring.

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1N1···Cl1ⁱ	0.87	2.26	3.1155 (10)	167
N1—H2N1···Cl1ⁱⁱ	0.87	2.23	3.0956 (10)	177
C3—H3A···Cg2ⁱⁱⁱ	0.97	2.79	3.5342 (11)	134

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

Experimental details

Crystal data
Chemical formula	C₁₁H₁₇N₂⁺·Cl⁻
M_r	212.72
Crystal system, space group	Orthorhombic, P2₁2₁2₁
Temperature (K)	296
a, b, c (Å)	8.1572 (2), 11.2821 (3), 12.4256 (3)
V (Å³)	1143.53 (5)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.30
Crystal size (mm)	0.54 × 0.33 × 0.23

Data collection
Diffractometer	Bruker APEX DUO CCD diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2009)
T_min, T_max	0.854, 0.936
No. of measured, independent and observed [I > 2σ(I)] reflections	8246, 4871, 4172
R_int	0.016
(sin θ/λ)_max (Å⁻¹)	0.816

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.032, 0.092, 0.95
No. of reflections	4871
No. of parameters	128
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.23, −0.19
Absolute structure	Flack (1983), 1943 Friedel pairs
Absolute structure parameter	0.02 (4)

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

Cg2 is the centroid of C5–C10 ring.

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1N1···Cl1ⁱ	0.87	2.26	3.1155 (10)	167
N1—H2N1···Cl1ⁱⁱ	0.87	2.23	3.0956 (10)	177
C3—H3A···Cg2ⁱⁱⁱ	0.97	2.79	3.5342 (11)	134

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

Footnotes

‡Thomson Reuters ResearcherID: A-3561-2009.

Acknowledgements

HKF and SIJA thank Universiti Sains Malaysia for the Research University Grants (Nos.1001/PFIZIK/811160 and 1001/PFIZIK/811151). AMI thanks the Board for Research in Nuclear Sciences, Department of Atomic Energy and Government of India, for the Young Scientist award.

References

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Volume 67| Part 11| November 2011| Page o3115

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