9-(1H-Benzo[d]imidazol-2-yl)-2,3,6,7-tetra­hydro-1H,5H-pyrido[3,2,1-ij]quinoline

González, G.G.; Unnamatla, M.V.B.

doi:10.1107/S241431461700445X

organic compounds

IUCrDATA

ISSN: 2414-3146

Volume 2| Part 3| March 2017| x170445

https://doi.org/10.1107/S241431461700445X

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9-(1H-Benzo[d]imidazol-2-yl)-2,3,6,7-tetrahydro-1H,5H-pyrido[3,2,1-ij]quinoline

Gerardo García González ^a and M. V. Basavanag Unnamatla ^a ^*

^aDepartamento de Química, Universidad de Guanajuato, Noria Alta S/N, Col. Noria Alta, CP 36050, Guanajuato, Gto., Mexico
^*Correspondence e-mail: muralivenkat@ugto.mx

Edited by S. Bernès, Benemérita Universidad Autónoma de Puebla, México (Received 15 January 2017; accepted 21 March 2017; online 28 March 2017)

The title compound, C₁₉H₁₉N₃, is a 2-heteroaryl benzimidazole derivative obtained through a straightforward and efficient protocol starting from julolidine-9-carbaldehyde and 1,2-phenylendiamine. The mean planes of the heterocyclic moieties in the molecule, benzimidazole and julolidine, form a dihedral angle of 40.9 (1)°. In the crystal, N—H⋯N hydrogen bonds link the imidazole rings, forming chains along the c-axis direction.

Keywords: crystal structure; benzimidazole; 2-heteroaryl benzimidazole; julolidine; hydrogen bonds.

CCDC reference: 1539272

Structure description

Benzimidazole derivatives play an important role as pharmacophores in pharmaceuticals, and have been shown to possess different biological properties, such as antioxidant (Ayhan-Kilcigil et al., 2004 ) and antifungal (Preston et al., 1974 ) activity. We present here the crystal structure of a 2-heteroaryl benzimidazole derivative (Fig. 1). The compound contains two heterocycles, which are skewed with an N1—C1—C8—C9 torsion angle of −34.7 (5)°. The dihedral angle between the mean planes of the benzimidazole and the julolidine moieties is 40.9 (1)°.

Figure 1
The molecular structure of the compound, showing displacement ellipsoids drawn at the 50% probability level.

In the crystal, a supramolecular structure based on intermolecular N2—H2⋯N1ⁱ hydrogen bonds is formed (Table 1), featuring zigzag chains of molecules in the [001] direction (Fig. 2).

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N2—H2⋯N1ⁱ	0.88	1.98	2.852 (4)	173
Symmetry code: (i) $[-x+{\script{1\over 2}}, y, z+{\script{1\over 2}}]$ .

Figure 2
Crystal-packing diagram, viewed along the c axis. The chain motifs are normal to the projection view.

Synthesis and crystallization

The title compound was synthesized (Fig. 3) by mixing equimolar amounts of o-phenylenediamine (1 mmol) and 9-julolidine carboxaldehyde (1 mmol) in ethanol. The resulting mixture was refluxed for 3 h. After cooling to room temperature, the solvents were removed under reduced pressure, and the residue purified by silica gel chromatography with petroleum ether/ethylacetate (6:4, v:v) as eluent, to afford the title compound as a colourless solid (95% yield). The compound was recrystallized from petroleum ether/diethyl ether (1:1, v:v).

Figure 3
The reaction scheme.

¹H NMR (500 MHz, CDCl₃), δ (p.p.m.): 7.57 (s, 1H), 7.50 (s, 2H), 7.26 (s, 2H), 7.20 (dd, J = 6.0, 3.1 Hz, 2H), 3.24–3.21 (m, 4H), 2.78 (t, J = 6.3 Hz, 4H), 2.00–1.94 (m, 4H). ¹³C NMR (126 MHz, CDCl₃), δ (p.p.m.): 152.8, 144.8, 125.5, 122.4, 121.4, 50.0, 27.8, 21.8.

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2. The methylene C atoms (C11, C12, C13, C16, C17, C18) in the julolidine group were refined with restrained displacement parameters: rigid-bond restraints were applied and atoms closer than 2 Å were restrained to have similar U_ij parameters within a standard deviation of 0.04 Å²; finally, these C atoms were restrained to approximate an isotropic behaviour (Sheldrick, 2015 ).

Table 2
Experimental details

Crystal data
Chemical formula	C₁₉H₁₉N₃
M_r	289.37
Crystal system, space group	Orthorhombic, Pca2₁
Temperature (K)	100
a, b, c (Å)	14.0540 (11), 11.2639 (6), 9.6184 (5)
V (Å³)	1522.62 (16)
Z	4
Radiation type	Mo Kα
μ (mm⁻¹)	0.08
Crystal size (mm)	0.53 × 0.34 × 0.26

Data collection
Diffractometer	Rigaku OD SuperNova, Single source at offset, EosS2
Absorption correction	Multi-scan (CrysAlis PRO; Rigaku OD, 2015 $[Rigaku OD (2015). CrysAlis PRO. Rigaku Oxford Diffraction Ltd, Yarnton, England.]$ )
T_min, T_max	0.878, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections	4617, 2727, 2528
R_int	0.021
(sin θ/λ)_max (Å⁻¹)	0.691

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.056, 0.154, 1.05
No. of reflections	2727
No. of parameters	200
No. of restraints	67
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.79, −0.34
Computer programs: CrysAlis PRO (Rigaku OD, 2015 $[Rigaku OD (2015). CrysAlis PRO. Rigaku Oxford Diffraction Ltd, Yarnton, England.]$ ), olex2.solve (Bourhis et al., 2015 ), SHELXL2014 (Sheldrick, 2015) and OLEX2 (Dolomanov et al., 2009 ).

Structural data

CCDC reference: 1539272

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S241431461700445X/bh4024sup1.cif

Supporting information file. DOI: https://doi.org/10.1107/S241431461700445X/bh4024Isup3.cdx

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S241431461700445X/bh4024Isup4.hkl

Supporting information file. DOI: https://doi.org/10.1107/S241431461700445X/bh4024Isup4.cml

checkCIF report

Computing details top

Data collection: CrysAlis PRO (Rigaku OD, 2015); cell refinement: CrysAlis PRO (Rigaku OD, 2015); data reduction: CrysAlis PRO (Rigaku OD, 2015); program(s) used to solve structure: olex2.solve (Bourhis et al., 2015); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009).

9-(1H-Benzo[d]imidazol-2-yl)-2,3,6,7-tetrahydro-1H,5H-pyrido[3,2,1-ij]quinoline top

Crystal data top

C₁₉H₁₉N₃	D_x = 1.262 Mg m⁻³
M_r = 289.37	Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, Pca2₁	Cell parameters from 2311 reflections
a = 14.0540 (11) Å	θ = 4.4–28.4°
b = 11.2639 (6) Å	µ = 0.08 mm⁻¹
c = 9.6184 (5) Å	T = 100 K
V = 1522.62 (16) Å³	Block, colourless
Z = 4	0.53 × 0.34 × 0.26 mm
F(000) = 616

Data collection top

Rigaku OD SuperNova, Single source at offset, EosS2 diffractometer	2727 independent reflections
Radiation source: SuperNova (Mo) X-ray Source	2528 reflections with I > 2σ(I)
Detector resolution: 8.0945 pixels mm^-1	R_int = 0.021
ω scans	θ_max = 29.4°, θ_min = 3.4°
Absorption correction: multi-scan (CrysAlis PRO; Rigaku OD, 2015)	h = −18→10
T_min = 0.878, T_max = 1.000	k = −15→13
4617 measured reflections	l = −13→11

Refinement top

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)] = 0.056	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.154	H-atom parameters constrained
S = 1.05	w = 1/[σ²(F_o²) + (0.0917P)² + 0.6633P] where P = (F_o² + 2F_c²)/3
2727 reflections	(Δ/σ)_max < 0.001
200 parameters	Δρ_max = 0.79 e Å⁻³
67 restraints	Δρ_min = −0.34 e Å⁻³
0 constraints

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.

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

	x	y	z	U_iso*/U_eq
N1	0.1962 (2)	0.8178 (2)	0.3418 (3)	0.0216 (6)
N2	0.2282 (2)	0.8416 (2)	0.5680 (3)	0.0200 (6)
H2	0.253182	0.828378	0.650431	0.029 (11)*
N3	0.4176 (2)	0.3248 (2)	0.5017 (3)	0.0286 (7)
C1	0.2398 (2)	0.7740 (2)	0.4529 (3)	0.0184 (6)
C2	0.1513 (2)	0.9199 (3)	0.3887 (3)	0.0215 (7)
C3	0.1697 (2)	0.9357 (3)	0.5316 (3)	0.0213 (7)
C4	0.1295 (3)	1.0267 (3)	0.6076 (4)	0.0285 (8)
H4	0.142022	1.035931	0.704076	0.034*
C5	0.0695 (3)	1.1045 (3)	0.5363 (4)	0.0345 (9)
H5	0.040386	1.168141	0.585225	0.041*
C6	0.0517 (3)	1.0907 (3)	0.3954 (5)	0.0341 (8)
H6	0.010790	1.145665	0.350216	0.041*
C7	0.0913 (3)	0.9995 (3)	0.3184 (4)	0.0284 (8)
H7	0.078437	0.991119	0.221969	0.034*
C8	0.2907 (2)	0.6604 (2)	0.4590 (3)	0.0189 (6)
C9	0.2574 (3)	0.5634 (3)	0.3814 (4)	0.0239 (7)
H9	0.205427	0.573953	0.319546	0.029*
C10	0.2991 (3)	0.4531 (3)	0.3937 (4)	0.0253 (7)
C11	0.2605 (3)	0.3483 (3)	0.3122 (5)	0.0415 (11)
H11A	0.190698	0.356295	0.301694	0.050*
H11B	0.289195	0.347109	0.218247	0.050*
C12	0.2833 (3)	0.2335 (3)	0.3871 (6)	0.0477 (12)
H12A	0.244727	0.228660	0.473014	0.057*
H12B	0.265494	0.165665	0.326989	0.057*
C13	0.3849 (3)	0.2240 (3)	0.4236 (5)	0.0405 (10)
H13A	0.395126	0.150983	0.478932	0.049*
H13B	0.422914	0.217004	0.337263	0.049*
C14	0.3775 (2)	0.4364 (3)	0.4838 (3)	0.0211 (7)
C15	0.4143 (2)	0.5353 (3)	0.5566 (3)	0.0223 (7)
C16	0.5092 (3)	0.3136 (3)	0.5706 (5)	0.0398 (9)
H16A	0.560227	0.327935	0.501689	0.048*
H16B	0.516213	0.231204	0.604927	0.048*
C17	0.5219 (4)	0.3968 (4)	0.6891 (6)	0.0535 (13)
H17A	0.588222	0.391328	0.723392	0.064*
H17B	0.479037	0.373227	0.765948	0.064*
C18	0.5012 (3)	0.5218 (3)	0.6485 (4)	0.0338 (9)
H18A	0.557154	0.554489	0.599026	0.041*
H18B	0.491807	0.569539	0.733895	0.041*
C19	0.3690 (2)	0.6436 (3)	0.5452 (3)	0.0208 (6)
H19	0.392053	0.708810	0.597922	0.025*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N1	0.0255 (15)	0.0238 (12)	0.0156 (12)	−0.0003 (11)	−0.0014 (12)	−0.0011 (10)
N2	0.0275 (15)	0.0200 (11)	0.0126 (12)	0.0018 (10)	0.0012 (12)	0.0003 (10)
N3	0.0309 (16)	0.0221 (13)	0.0328 (16)	0.0040 (12)	0.0029 (14)	−0.0037 (11)
C1	0.0201 (15)	0.0214 (13)	0.0138 (13)	−0.0034 (11)	0.0027 (13)	−0.0010 (11)
C2	0.0269 (17)	0.0201 (14)	0.0175 (14)	−0.0017 (12)	0.0023 (14)	0.0019 (12)
C3	0.0238 (17)	0.0211 (13)	0.0191 (14)	−0.0007 (13)	0.0039 (14)	0.0014 (12)
C4	0.036 (2)	0.0284 (16)	0.0213 (16)	0.0023 (15)	0.0019 (16)	−0.0037 (13)
C5	0.040 (2)	0.0254 (15)	0.038 (2)	0.0084 (15)	0.0080 (19)	−0.0031 (15)
C6	0.037 (2)	0.0283 (17)	0.0370 (19)	0.0070 (15)	−0.0026 (19)	0.0035 (15)
C7	0.034 (2)	0.0272 (15)	0.0242 (16)	−0.0003 (15)	−0.0042 (16)	0.0037 (13)
C8	0.0220 (16)	0.0210 (13)	0.0137 (12)	−0.0005 (12)	0.0037 (13)	−0.0005 (11)
C9	0.0244 (17)	0.0264 (14)	0.0209 (14)	−0.0006 (13)	−0.0047 (14)	−0.0056 (13)
C10	0.0277 (18)	0.0234 (15)	0.0247 (15)	−0.0009 (13)	−0.0044 (16)	−0.0051 (13)
C11	0.046 (3)	0.0287 (16)	0.050 (3)	0.0014 (17)	−0.020 (2)	−0.0132 (17)
C12	0.041 (2)	0.0299 (18)	0.072 (3)	−0.0051 (16)	−0.004 (3)	−0.013 (2)
C13	0.056 (3)	0.0210 (16)	0.044 (2)	0.0042 (16)	−0.010 (2)	−0.0074 (15)
C14	0.0245 (17)	0.0221 (13)	0.0167 (15)	0.0002 (12)	0.0044 (14)	−0.0009 (11)
C15	0.0236 (16)	0.0273 (14)	0.0160 (14)	0.0017 (12)	0.0000 (14)	−0.0006 (12)
C16	0.046 (2)	0.0370 (18)	0.0358 (19)	0.0163 (18)	−0.012 (2)	−0.0017 (17)
C17	0.054 (3)	0.049 (2)	0.057 (3)	0.012 (2)	−0.023 (3)	−0.002 (2)
C18	0.034 (2)	0.0352 (18)	0.0320 (19)	0.0059 (17)	−0.0124 (18)	−0.0063 (15)
C19	0.0250 (16)	0.0235 (13)	0.0139 (14)	−0.0047 (12)	0.0004 (14)	−0.0026 (11)

Geometric parameters (Å, º) top

N1—C1	1.327 (4)	C10—C14	1.415 (5)
N1—C2	1.387 (4)	C10—C11	1.517 (5)
N2—C1	1.354 (4)	C11—C12	1.514 (6)
N2—C3	1.386 (4)	C11—H11A	0.9900
N2—H2	0.8800	C11—H11B	0.9900
N3—C14	1.388 (4)	C12—C13	1.475 (6)
N3—C13	1.438 (5)	C12—H12A	0.9900
N3—C16	1.452 (5)	C12—H12B	0.9900
C1—C8	1.467 (4)	C13—H13A	0.9900
C2—C7	1.405 (5)	C13—H13B	0.9900
C2—C3	1.410 (5)	C14—C15	1.413 (4)
C3—C4	1.380 (5)	C15—C19	1.380 (4)
C4—C5	1.396 (5)	C15—C18	1.516 (5)
C4—H4	0.9500	C16—C17	1.487 (6)
C5—C6	1.387 (6)	C16—H16A	0.9900
C5—H5	0.9500	C16—H16B	0.9900
C6—C7	1.383 (5)	C17—C18	1.490 (6)
C6—H6	0.9500	C17—H17A	0.9900
C7—H7	0.9500	C17—H17B	0.9900
C8—C19	1.390 (5)	C18—H18A	0.9900
C8—C9	1.403 (4)	C18—H18B	0.9900
C9—C10	1.379 (4)	C19—H19	0.9500
C9—H9	0.9500

C1—N1—C2	104.9 (3)	C10—C11—H11B	109.7
C1—N2—C3	107.2 (3)	H11A—C11—H11B	108.2
C1—N2—H2	126.4	C13—C12—C11	112.4 (4)
C3—N2—H2	126.4	C13—C12—H12A	109.1
C14—N3—C13	121.4 (3)	C11—C12—H12A	109.1
C14—N3—C16	119.7 (3)	C13—C12—H12B	109.1
C13—N3—C16	116.9 (3)	C11—C12—H12B	109.1
N1—C1—N2	113.2 (3)	H12A—C12—H12B	107.9
N1—C1—C8	125.6 (3)	N3—C13—C12	112.1 (3)
N2—C1—C8	121.1 (3)	N3—C13—H13A	109.2
N1—C2—C7	130.3 (3)	C12—C13—H13A	109.2
N1—C2—C3	109.8 (3)	N3—C13—H13B	109.2
C7—C2—C3	119.9 (3)	C12—C13—H13B	109.2
C4—C3—N2	132.6 (3)	H13A—C13—H13B	107.9
C4—C3—C2	122.4 (3)	N3—C14—C15	120.2 (3)
N2—C3—C2	105.0 (3)	N3—C14—C10	120.8 (3)
C3—C4—C5	117.0 (3)	C15—C14—C10	118.9 (3)
C3—C4—H4	121.5	C19—C15—C14	119.2 (3)
C5—C4—H4	121.5	C19—C15—C18	120.5 (3)
C6—C5—C4	121.2 (3)	C14—C15—C18	120.3 (3)
C6—C5—H5	119.4	N3—C16—C17	113.7 (3)
C4—C5—H5	119.4	N3—C16—H16A	108.8
C7—C6—C5	122.3 (4)	C17—C16—H16A	108.8
C7—C6—H6	118.9	N3—C16—H16B	108.8
C5—C6—H6	118.9	C17—C16—H16B	108.8
C6—C7—C2	117.3 (3)	H16A—C16—H16B	107.7
C6—C7—H7	121.3	C16—C17—C18	111.8 (4)
C2—C7—H7	121.3	C16—C17—H17A	109.3
C19—C8—C9	118.3 (3)	C18—C17—H17A	109.3
C19—C8—C1	121.9 (3)	C16—C17—H17B	109.3
C9—C8—C1	119.7 (3)	C18—C17—H17B	109.3
C10—C9—C8	121.0 (3)	H17A—C17—H17B	107.9
C10—C9—H9	119.5	C17—C18—C15	113.9 (3)
C8—C9—H9	119.5	C17—C18—H18A	108.8
C9—C10—C14	120.2 (3)	C15—C18—H18A	108.8
C9—C10—C11	120.3 (3)	C17—C18—H18B	108.8
C14—C10—C11	119.5 (3)	C15—C18—H18B	108.8
C12—C11—C10	110.0 (3)	H18A—C18—H18B	107.7
C12—C11—H11A	109.7	C15—C19—C8	122.2 (3)
C10—C11—H11A	109.7	C15—C19—H19	118.9
C12—C11—H11B	109.7	C8—C19—H19	118.9

C2—N1—C1—N2	−1.3 (4)	C14—C10—C11—C12	25.5 (6)
C2—N1—C1—C8	174.5 (3)	C10—C11—C12—C13	−51.3 (5)
C3—N2—C1—N1	2.1 (4)	C14—N3—C13—C12	−30.0 (5)
C3—N2—C1—C8	−174.0 (3)	C16—N3—C13—C12	166.2 (4)
C1—N1—C2—C7	−176.8 (4)	C11—C12—C13—N3	54.2 (6)
C1—N1—C2—C3	0.1 (4)	C13—N3—C14—C15	−176.7 (3)
C1—N2—C3—C4	175.1 (4)	C16—N3—C14—C15	−13.4 (5)
C1—N2—C3—C2	−1.9 (3)	C13—N3—C14—C10	3.8 (5)
N1—C2—C3—C4	−176.3 (3)	C16—N3—C14—C10	167.1 (3)
C7—C2—C3—C4	1.0 (5)	C9—C10—C14—N3	177.2 (3)
N1—C2—C3—N2	1.1 (4)	C11—C10—C14—N3	−2.0 (5)
C7—C2—C3—N2	178.4 (3)	C9—C10—C14—C15	−2.3 (5)
N2—C3—C4—C5	−177.1 (4)	C11—C10—C14—C15	178.5 (4)
C2—C3—C4—C5	−0.6 (5)	N3—C14—C15—C19	−175.2 (3)
C3—C4—C5—C6	−0.1 (6)	C10—C14—C15—C19	4.3 (5)
C4—C5—C6—C7	0.4 (7)	N3—C14—C15—C18	3.4 (5)
C5—C6—C7—C2	0.0 (6)	C10—C14—C15—C18	−177.0 (3)
N1—C2—C7—C6	175.9 (4)	C14—N3—C16—C17	38.2 (5)
C3—C2—C7—C6	−0.7 (5)	C13—N3—C16—C17	−157.8 (4)
N1—C1—C8—C19	148.5 (3)	N3—C16—C17—C18	−51.9 (6)
N2—C1—C8—C19	−36.0 (5)	C16—C17—C18—C15	41.9 (6)
N1—C1—C8—C9	−34.7 (5)	C19—C15—C18—C17	160.0 (4)
N2—C1—C8—C9	140.9 (3)	C14—C15—C18—C17	−18.6 (5)
C19—C8—C9—C10	2.2 (5)	C14—C15—C19—C8	−3.1 (5)
C1—C8—C9—C10	−174.7 (3)	C18—C15—C19—C8	178.2 (3)
C8—C9—C10—C14	−1.0 (6)	C9—C8—C19—C15	−0.1 (5)
C8—C9—C10—C11	178.2 (4)	C1—C8—C19—C15	176.8 (3)
C9—C10—C11—C12	−153.7 (4)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2···N1ⁱ	0.88	1.98	2.852 (4)	173

Symmetry code: (i) −x+1/2, y, z+1/2.

Acknowledgements

The authors are grateful to the Universidad de Guanajuato for access to the single-crystal analysis facility.

Funding information

Funding for this research was provided by: Consejo Nacional de Ciencia y Tecnología (award No. 123732); Universidad de Guanajuato (award No. DAIP-1105/2016).

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