Crystal structure of 2-(1H-imidazol-4-yl)ethanaminium chloride

The title mol­ecular salt, C₅H₁₀N₃⁺·Cl⁻, was obtained as by-product in the attempted synthesis of a histamine derivative. The terminal amino group of the starting material is protonated. The C_imidazole—C—C—N(H₃)⁺ group in the cation is in an anti conformation with a torsion angle of 176.22 (10)°. In the crystal, cations and anions are linked via N—H⋯N and N—H—Cl hydrogen bonds, forming a two-dimensional network parallel to (10-1). A single weak C—H⋯Cl hydrogen bond completes a three-dimensional network.

1. Related literature

For the biological and pharmacological applications of histamine derivatives, see: Barnes et al. (2001); Schwartz et al. (1991); Bachert et al. (1998); Emanuel et al. (1999); Apáti et al. (2012). For a study of a histamine copper(II) chloride complex, see: Belfilali et al. (2015). For the general chemistry of transition metal ions with histamine, see: Mikulski et al. (2012); Kowalik-Jankowska et al. (2010); Selmeczi et al. (2012). For a related structure, see: Prout et al. (1974).

2. Experimental

2.1. Crystal data

• C₅H₁₀N₃⁺·Cl⁻

• M_r = 147.61

• Monoclinic, P 2₁ /n

• a = 4.5840 (2) Å

• b = 9.1614 (3) Å

• c = 17.3114 (5) Å

• β = 91.682 (1)°

• V = 726.69 (4) ų

• Z = 4

• Mo Kα radiation

• μ = 0.44 mm⁻¹

• T = 150 K

• 0.41 × 0.13 × 0.08 mm

2.2. Data collection

• Bruker APEXII diffractometer

• Absorption correction: multi-scan (SADABS; Bruker, 2006)' T_min = 0.868, T_max = 0.965

• 5568 measured reflections

• 1645 independent reflections

• 1494 reflections with I > 2σ(I)

• R_int = 0.033

2.3. Refinement

• R[F² > 2σ(F²)] = 0.028

• wR(F²) = 0.076

• S = 1.08

• 1645 reflections

• 86 parameters

• H atoms treated by a mixture of independent and constrained refinement

• Δρ_max = 0.34 e Å⁻³

• Δρ_min = −0.21 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1A⋯N5^i	0.91	1.96	2.8508 (15)	168
N1—H1B⋯Cl1^i	0.91	2.28	3.1557 (11)	160
N1—H1C⋯Cl1^ii	0.91	2.39	3.2443 (11)	157
N7—H7⋯Cl1^iii	0.78 (2)	2.40 (2)	3.1645 (12)	168 (2)
C2—H2A⋯Cl1^iv	0.99	2.72	3.6974 (14)	168
Symmetry codes: (i) -x+1, -y+1, -z; (ii) x, y+1, z; (iii) ; (iv) x+1, y+1, z.

Data collection: APEX2 (Bruker, 2006); cell refinement: SAINT (Bruker, 2006); data reduction: SAINT; program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and PLATON (Spek, 2009); software used to prepare material for publication: WinGX publication routines (Farrugia, 2012) and CRYSCAL (T. Roisnel, local program).

Supporting information

S1. Structural commentary

Histamine (2-(1H-imidazol-4-yl)ethanamine) is a biogenic amine present in essentially all mammalian tissues and involved in several defense mechanisms of the body. It plays a role in various physiological processes, such as control of gastric acid secretion, neurotransmission, regulation of the microcirculation, and modulation of inflammatory (Barnes et al., 2001) and immunological reactions (Schwartz et al., 1991; Bachert et al., 1998; Emanuel et al., 1999) as well as its uses in pharmacology (Apáti et al., 2012). Moreover, the inter­action of transition metal ions with histamine (Mikulski et al., 2012), play a key role in catalysis processes (Kowalik-Jankowska et al., 2010; Selmeczi et al., 2012). We have previously reported the preparation and the crystal structure of the histamine copper(II) chloride complex and its catalytic activity study (Belfilali et al., 2015). In this study, we report the synthesis and crystal structure determination of the title compound.

The molecular structure of the title compound is shown in Fig. 1. The organic cation displays a trans conformation with respect to the amine group and the imidazole ring about the –CH₂—CH₂– bond of the side chain with a torsion angle of 176.22 (10)° for N1–C2–C3–C4. The bond lengths and angles are within normal ranges and are comparable to a related structure (Prout et al., 1974). In the crystal, cations and anions are linked via N—H···N and N—H—Cl hydrogen bonds two form a two-dimensional network (Fig. 2) parallel to (101). A single weak C—H···Cl hydrogen bond completes a three-dimensinal network.

S2. Synthesis and crystallization

A mixture of histamine di­hydro­chloride (1.0 mmol) and methyl-1hy­droxy-2-naphtho­ate (1 mmol) were taken in a beaker placed in a microwave oven and irradiated at 200 watt for 5 minutes. After completion the reaction, the reaction mixture was allowed to reach room temperature and the resulting crystals were separated by filtration.

S3. Refinement

H atoms bonded to C atoms were included in calculated positions with C—H = 0.95 – 0.99 Å and U_iso(H) = 1.2U_eq(C). H atoms bonded to N1 were included in calculated positions with N—H = 0.91Å and U_iso(H) = 1.5U_eq(N). The H atom bonded to N7 was refined independently with an isotropic displacement parameter.

Related literature

For the biological and pharmacological applications of histamine derivatives, see: Barnes et al. (2001); Schwartz et al. (1991); Bachert et al. (1998); Emanuel et al. (1999); Apáti et al. (2012). For a study of a histamine copper(II) chloride complex, see: Belfilali et al. (2015). For the general chemistry of transition metal ions with histamine, see: Mikulski et al. (2012); Kowalik-Jankowska et al. (2010); Selmeczi et al. (2012). For a related structure, see: Prout et al. (1974).

Structure description

Histamine (2-(1H-imidazol-4-yl)ethanamine) is a biogenic amine present in essentially all mammalian tissues and involved in several defense mechanisms of the body. It plays a role in various physiological processes, such as control of gastric acid secretion, neurotransmission, regulation of the microcirculation, and modulation of inflammatory (Barnes et al., 2001) and immunological reactions (Schwartz et al., 1991; Bachert et al., 1998; Emanuel et al., 1999) as well as its uses in pharmacology (Apáti et al., 2012). Moreover, the inter­action of transition metal ions with histamine (Mikulski et al., 2012), play a key role in catalysis processes (Kowalik-Jankowska et al., 2010; Selmeczi et al., 2012). We have previously reported the preparation and the crystal structure of the histamine copper(II) chloride complex and its catalytic activity study (Belfilali et al., 2015). In this study, we report the synthesis and crystal structure determination of the title compound.

The molecular structure of the title compound is shown in Fig. 1. The organic cation displays a trans conformation with respect to the amine group and the imidazole ring about the –CH₂—CH₂– bond of the side chain with a torsion angle of 176.22 (10)° for N1–C2–C3–C4. The bond lengths and angles are within normal ranges and are comparable to a related structure (Prout et al., 1974). In the crystal, cations and anions are linked via N—H···N and N—H—Cl hydrogen bonds two form a two-dimensional network (Fig. 2) parallel to (101). A single weak C—H···Cl hydrogen bond completes a three-dimensinal network.

For the biological and pharmacological applications of histamine derivatives, see: Barnes et al. (2001); Schwartz et al. (1991); Bachert et al. (1998); Emanuel et al. (1999); Apáti et al. (2012). For a study of a histamine copper(II) chloride complex, see: Belfilali et al. (2015). For the general chemistry of transition metal ions with histamine, see: Mikulski et al. (2012); Kowalik-Jankowska et al. (2010); Selmeczi et al. (2012). For a related structure, see: Prout et al. (1974).

Synthesis and crystallization

A mixture of histamine di­hydro­chloride (1.0 mmol) and methyl-1hy­droxy-2-naphtho­ate (1 mmol) were taken in a beaker placed in a microwave oven and irradiated at 200 watt for 5 minutes. After completion the reaction, the reaction mixture was allowed to reach room temperature and the resulting crystals were separated by filtration.

Refinement details

H atoms bonded to C atoms were included in calculated positions with C—H = 0.95 – 0.99 Å and U_iso(H) = 1.2U_eq(C). H atoms bonded to N1 were included in calculated positions with N—H = 0.91Å and U_iso(H) = 1.5U_eq(N). The H atom bonded to N7 was refined independently with an isotropic displacement parameter.

Computing details

Data collection: APEX2 (Bruker, 2006); cell refinement: SAINT (Bruker, 2006); data reduction: SAINT (Bruker, 2006); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and PLATON (Spek, 2009); software used to prepare material for publication: WinGX publication routines (Farrugia, 2012) and CRYSCAL (T. Roisnel, local program).

Figures

	Fig. 1. The molecular structure of the title compound. Displacement ellipsoids are drawn at the 50% probability level.
	Fig. 2. Part of the crystal structure with hydrogen bonds shown as dashed lines.

2-(1H-Imidazol-4-yl)ethanaminium chloride

Crystal data

C5H10N3^+·Cl^−	F(000) = 312
Mr = 147.61	Dx = 1.349 Mg m^−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 2978 reflections
a = 4.5840 (2) Å	θ = 4.6–27.5°
b = 9.1614 (3) Å	µ = 0.44 mm^−1
c = 17.3114 (5) Å	T = 150 K
β = 91.682 (1)°	Prism, colourless
V = 726.69 (4) Å^3	0.41 × 0.13 × 0.08 mm
Z = 4

Data collection

Bruker APEXII diffractometer	1494 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.033
CCD rotation images, thin slices scans	θmax = 27.5°, θmin = 3.2°
Absorption correction: multi-scan (SADABS; Bruker, 2006)'	h = −5→5
Tmin = 0.868, Tmax = 0.965	k = −11→11
5568 measured reflections	l = −19→22
1645 independent reflections

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.028	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.076	H atoms treated by a mixture of independent and constrained refinement
S = 1.08	w = 1/[σ^2(Fo^2) + (0.0331P)^2 + 0.246P] where P = (Fo^2 + 2Fc^2)/3
1645 reflections	(Δ/σ)max = 0.001
86 parameters	Δρmax = 0.34 e Å^−3
0 restraints	Δρmin = −0.21 e Å^−3

Special details

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.

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 > σ(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 (Ų)

	x	y	z	Uiso*/Ueq
N1	0.4106 (2)	0.80020 (12)	−0.01832 (6)	0.0174 (2)
H1A	0.3108	0.7313	−0.0462	0.026*
H1B	0.5029	0.8614	−0.051	0.026*
H1C	0.2838	0.8521	0.0104	0.026*
C2	0.6308 (3)	0.72762 (15)	0.03395 (7)	0.0174 (3)
H2A	0.7497	0.8028	0.0613	0.021*
H2B	0.7631	0.6675	0.0029	0.021*
C3	0.4835 (3)	0.63146 (15)	0.09277 (8)	0.0192 (3)
H3A	0.3615	0.6926	0.1262	0.023*
H3B	0.3543	0.5605	0.0655	0.023*
C4	0.7051 (3)	0.55095 (15)	0.14180 (7)	0.0169 (3)
N5	0.8253 (2)	0.41984 (12)	0.11844 (6)	0.0184 (2)
C6	1.0162 (3)	0.38371 (15)	0.17436 (7)	0.0197 (3)
H6	1.1334	0.2982	0.1741	0.024*
N7	1.0229 (3)	0.48288 (14)	0.23111 (7)	0.0223 (3)
H7	1.124 (5)	0.481 (2)	0.2682 (14)	0.05*
C8	0.8270 (3)	0.58985 (16)	0.21139 (8)	0.0229 (3)
H8	0.7842	0.6747	0.2405	0.027*
Cl1	0.13058 (7)	0.01456 (3)	0.108958 (17)	0.01841 (12)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
N1	0.0185 (5)	0.0155 (6)	0.0180 (5)	−0.0019 (4)	−0.0008 (4)	−0.0004 (4)
C2	0.0152 (6)	0.0180 (6)	0.0190 (6)	−0.0021 (5)	−0.0022 (5)	−0.0002 (5)
C3	0.0156 (6)	0.0200 (7)	0.0220 (7)	−0.0008 (5)	0.0007 (5)	0.0009 (5)
C4	0.0160 (6)	0.0180 (6)	0.0169 (6)	−0.0017 (5)	0.0031 (5)	0.0006 (5)
N5	0.0206 (5)	0.0155 (5)	0.0189 (5)	−0.0016 (4)	−0.0018 (4)	−0.0006 (5)
C6	0.0218 (6)	0.0176 (6)	0.0197 (6)	−0.0007 (5)	−0.0012 (5)	0.0015 (5)
N7	0.0238 (6)	0.0268 (6)	0.0161 (6)	0.0001 (5)	−0.0041 (5)	−0.0009 (5)
C8	0.0252 (7)	0.0233 (7)	0.0202 (7)	0.0034 (6)	0.0008 (5)	−0.0046 (6)
Cl1	0.02061 (18)	0.01856 (18)	0.01589 (19)	−0.00105 (12)	−0.00236 (12)	−0.00087 (11)

Geometric parameters (Å, º)

N1—C2	1.4920 (16)	C3—H3B	0.99
N1—H1A	0.91	C4—C8	1.3604 (18)
N1—H1B	0.91	C4—N5	1.3866 (17)
N1—H1C	0.91	N5—C6	1.3277 (16)
C2—C3	1.5196 (18)	C6—N7	1.3379 (18)
C2—H2A	0.99	C6—H6	0.95
C2—H2B	0.99	N7—C8	1.3658 (18)
C3—C4	1.4985 (18)	N7—H7	0.78 (2)
C3—H3A	0.99	C8—H8	0.95
C2—N1—H1A	109.5	C2—C3—H3B	109.4
C2—N1—H1B	109.5	H3A—C3—H3B	108
H1A—N1—H1B	109.5	C8—C4—N5	109.20 (11)
C2—N1—H1C	109.5	C8—C4—C3	128.79 (13)
H1A—N1—H1C	109.5	N5—C4—C3	121.99 (11)
H1B—N1—H1C	109.5	C6—N5—C4	105.21 (11)
N1—C2—C3	111.03 (10)	N5—C6—N7	111.50 (12)
N1—C2—H2A	109.4	N5—C6—H6	124.2
C3—C2—H2A	109.4	N7—C6—H6	124.2
N1—C2—H2B	109.4	C6—N7—C8	107.63 (11)
C3—C2—H2B	109.4	C6—N7—H7	126.3 (16)
H2A—C2—H2B	108	C8—N7—H7	126.1 (16)
C4—C3—C2	110.96 (10)	C4—C8—N7	106.46 (12)
C4—C3—H3A	109.4	C4—C8—H8	126.8
C2—C3—H3A	109.4	N7—C8—H8	126.8
C4—C3—H3B	109.4
N1—C2—C3—C4	176.22 (10)	C4—N5—C6—N7	0.21 (15)
C2—C3—C4—C8	93.03 (17)	N5—C6—N7—C8	−0.18 (16)
C2—C3—C4—N5	−84.87 (15)	N5—C4—C8—N7	0.06 (15)
C8—C4—N5—C6	−0.16 (15)	C3—C4—C8—N7	−178.06 (12)
C3—C4—N5—C6	178.11 (12)	C6—N7—C8—C4	0.07 (16)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···N5^i	0.91	1.96	2.8508 (15)	168
N1—H1B···Cl1^i	0.91	2.28	3.1557 (11)	160
N1—H1C···Cl1^ii	0.91	2.39	3.2443 (11)	157
N7—H7···Cl1^iii	0.78 (2)	2.40 (2)	3.1645 (12)	168 (2)
C2—H2A···Cl1^iv	0.99	2.72	3.6974 (14)	168

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