Crystal structure of 4-amino-1-benzyl-1,2,4-triazolin-5-one

Laus, G.; Kahlenberg, V.; Schottenberger, H.

doi:10.1107/S160053681401931X

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Volume 70| Part 10| October 2014| Pages o1083-o1084

doi:10.1107/S160053681401931X

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Crystal structure of 4-amino-1-benzyl-1,2,4-triazolin-5-one

Gerhard Laus,^a ^* Volker Kahlenberg ^b and Herwig Schottenberger ^a

^aUniversity of Innsbruck, Faculty of Chemistry and Pharmacy, Innrain 80, 6020 Innsbruck, Austria, and ^bUniversity of Innsbruck, Institute of Mineralogy and Petrography, Innrain 52, 6020 Innsbruck, Austria
^*Correspondence e-mail: gerhard.laus@uibk.ac.at

Edited by L. Farrugia, University of Glasgow, Scotland (Received 22 August 2014; accepted 26 August 2014; online 3 September 2014)

The title compound, C₉H₁₀N₄O, was obtained unintentionally by hydrolysis of 4-amino-1-benzyl-5-methylsulfanyl-1,2,4-triazolium tetrafluoroborate in the presence of sodium azide. In the crystal, alternating layers of polar aminotriazolinone and apolar benzene moieties are observed. N—H⋯O hydrogen bonds between the amino and carbonyl groups form infinite chains along [010]. These infinite chains are linked by additional C—H⋯O contacts.

Keywords: crystal structure; 1,2,4-triazolin-5-one; hydrogen bonding.

CCDC reference: 1021229

1. Related literature

For the pharmacological activity of 1,2,4-triazoles, see: Sheng et al. (2011 ); Singla & Bhat (2010 ); Dayan et al. (2009 ); Li et al. (2003 ); Todoulou et al. (1994 ). For related structures, see: Thamotharan et al. (2003 ); Kaur et al. (2013 ); Sahin et al. (2014 ). For details of the synthesis, see: Becker et al. (1973a ,b ). For a description of the Cambridge Structural Database, see: Groom & Allen (2014 ).

2. Experimental

2.1. Crystal data

C₉H₁₀N₄O
M_r = 190.21
Monoclinic, P 2₁ /c
a = 18.0861 (8) Å
b = 4.1690 (2) Å
c = 12.3694 (6) Å
β = 104.003 (5)°
V = 904.95 (7) Å³
Z = 4
Cu Kα radiation
μ = 0.80 mm⁻¹
T = 173 K
0.2 × 0.2 × 0.08 mm

2.2. Data collection

Oxford Diffraction Xcalibur (Ruby, Gemini ultra) diffractometer
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2010 $[Oxford Diffraction (2010). CrysAlis PRO. Oxford Diffraction Ltd, Abingdon, Oxfordshire, England.]$ ) T_min = 0.867, T_max = 1
7377 measured reflections
1613 independent reflections
1448 reflections with I > 2σ(I)
R_int = 0.030

2.3. Refinement

R[F² > 2σ(F²)] = 0.034
wR(F²) = 0.092
S = 1.03
1613 reflections
133 parameters
2 restraints
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.17 e Å⁻³
Δρ_min = −0.14 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N3—H32⋯O1ⁱ	0.90 (1)	2.47 (2)	3.0583 (15)	124 (1)
N3—H31⋯O1ⁱⁱ	0.90 (1)	2.22 (2)	3.0701 (16)	156 (2)
C2—H2⋯O1ⁱⁱⁱ	0.95	2.24	3.181 (2)	168
Symmetry codes: (i) -x+1, -y-1, -z+2; (ii) -x+1, -y, -z+2; (iii) $[x, -y-{\script{1\over 2}}, z-{\script{1\over 2}}]$ .

Data collection: CrysAlis PRO (Oxford Diffraction, 2010 $[Oxford Diffraction (2010). CrysAlis PRO. Oxford Diffraction Ltd, Abingdon, Oxfordshire, England.]$ ); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SIR2002 (Burla et al., 2002 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012 ); software used to prepare material for publication: SHELXL97.

Supporting information

CCDC reference: 1021229

Crystal structure: contains datablocks I, global. DOI: 10.1107/S160053681401931X/fj2680sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S160053681401931X/fj2680Isup2.hkl

Supporting information file. DOI: 10.1107/S160053681401931X/fj2680Isup3.mol

Supporting information file. DOI: 10.1107/S160053681401931X/fj2680Isup4.cml

checkCIF report

Comment top

1,2,4-Triazole derivatives possess a wide spectrum of pharmacological activities (Sheng et al., 2011; Singla & Bhat, 2010; Dayan et al., 2009; Li et al., 2003; Todoulou et al., 1994). Only three 1-substituted 4-amino-1,2,4-triazolin-5-ones (Thamotharan et al., 2003; Kaur et al., 2013; Sahin et al., 2014) are found in the Cambridge Structural Database (Groom & Allen, 2014). The molecular structure of 4-amino-1-benzyl-1,2,4-triazolin-5-one is shown in Figure 1. In the crystal structure of the title compound, alternating layers of polar aminotriazolinone and apolar benzene moieties parallel to the bc plane are observed (Figure 2). The triazole rings are arranged parallel to (13 4 3) and (13 4 3) planes, with an interplanar angle of 76° (Figure 3). The amino group donates two hydrogen bonds to two neighbouring molecules, N3—H···O1ⁱ and N3—H···O1ⁱⁱ, forming infinite chains (Figure 4). In turn, the O atom receives a hydrogen bond from each of these two molecules. The triazole rings within the chain are parallel, with interplanar distances of 0.730 and 2.558 Å, respectively. These infinite chains are linked by additional C2—H···O1ⁱⁱⁱ contacts. Symmetry operators (i): 1 - x, -1 - y, 2 - z; (ii): 1 - x, -y, 2 - z; (iii): x, -1/2 - y, -1/2 + z. Hydrogen bond geometry is shown in Table 1.

Related literature top

For the pharmacological activity of 1,2,4-triazoles, see: Sheng et al. (2011); Singla & Bhat (2010); Dayan et al. (2009); Li et al. (2003); Todoulou et al. (1994). For related structures, see: Thamotharan et al. (2003); Kaur et al. (2013); Sahin et al. (2014). For details of the synthesis, see: Becker et al. (1973a,b). For a description of the Cambridge Structural Database, see: Groom & Allen (2014).

Experimental top

The title compound was prepared from 4-amino-1-benzyl-5-methylthio-1,2,4- triazolium tetrafluoroborate (the respective iodide has been described by Becker et al., 1973b) which, in turn, was prepared from the corresponding 4-amino-1-benzyl-1,2,4-triazoline-5-thione (Becker et al., 1973a). When the 5-methylthio precursor was treated with NaN₃ in MeOH/H₂O, MeSH was evolved, and the triazolin-5-one was obtained. It is assumed that the intermediate 5-azido compound is highly prone to hydrolysis and therefore could not be isolated. In contrast, the 5-methylthio precursor could be stirred in H₂O for 20 h without any change. Single crystals were obtained from MeOH/H₂O. Melting point 119–120 °C. IR (neat): 1680 cm^-1. ¹H NMR (DMSO-d₆, 300 MHz): 4.85 (s, 2H), 5.43 (s, 2H), 7.23–7.33 (m, 5H), 7.93 (s, 1H) p.p.m.. ¹³C NMR (DMSO-d₆, 75 MHz): 48.7, 127.5 (3C), 128.5 (2C), 137.1, 138.4, 152.8 p.p.m..

Computing details top

Data collection: CrysAlis PRO (Oxford Diffraction, 2010); cell refinement: CrysAlis PRO (Oxford Diffraction, 2010); data reduction: CrysAlis PRO (Oxford Diffraction, 2010); program(s) used to solve structure: SIR2002 (Burla et al., 2002); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

	Fig. 1. The molecular structure of the title compound, with atom labels and 50% probability displacement ellipsoids for non-H atoms.
	Fig. 2. Alternating layers of polar aminotriazolinone and apolar benzene moieties.
	Fig. 3. Arrangement of the triazole rings parallel to (13 4 3) and (13 4 3) planes.
	Fig. 4. Hydrogen bonds between the amino and carbonyl groups form infinite chains. Symmetry operators (i): 1 - x, -1 - y, 2 - z; (ii): 1 - x, -y, 2 - z.

4-Amino-1-benzyl-1,2,4-triazolin-5-one top

Crystal data top

C₉H₁₀N₄O	F(000) = 400
M_r = 190.21	D_x = 1.396 Mg m⁻³
Monoclinic, P2₁/c	Cu Kα radiation, λ = 1.5418 Å
Hall symbol: -P 2ybc	Cell parameters from 4064 reflections
a = 18.0861 (8) Å	θ = 3.7–67.9°
b = 4.1690 (2) Å	µ = 0.80 mm⁻¹
c = 12.3694 (6) Å	T = 173 K
β = 104.003 (5)°	Plate, colourless
V = 904.95 (7) Å³	0.2 × 0.2 × 0.08 mm
Z = 4

Data collection top

Oxford Diffraction Xcalibur (Ruby, Gemini ultra) diffractometer	1613 independent reflections
Graphite monochromator	1448 reflections with I > 2σ(I)
Detector resolution: 10.3575 pixels mm^-1	R_int = 0.030
ω scans	θ_max = 68.0°, θ_min = 5.0°
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2010)	h = −21→21
T_min = 0.867, T_max = 1	k = −4→4
7377 measured reflections	l = −14→14

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)] = 0.034	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.092	H atoms treated by a mixture of independent and constrained refinement
S = 1.03	w = 1/[σ²(F_o²) + (0.0489P)² + 0.2066P] where P = (F_o² + 2F_c²)/3
1613 reflections	(Δ/σ)_max = 0.001
133 parameters	Δρ_max = 0.17 e Å⁻³
2 restraints	Δρ_min = −0.14 e Å⁻³

Crystal data top

C₉H₁₀N₄O	V = 904.95 (7) Å³
M_r = 190.21	Z = 4
Monoclinic, P2₁/c	Cu Kα radiation
a = 18.0861 (8) Å	µ = 0.80 mm⁻¹
b = 4.1690 (2) Å	T = 173 K
c = 12.3694 (6) Å	0.2 × 0.2 × 0.08 mm
β = 104.003 (5)°

Data collection top

Oxford Diffraction Xcalibur (Ruby, Gemini ultra) diffractometer	1613 independent reflections
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2010)	1448 reflections with I > 2σ(I)
T_min = 0.867, T_max = 1	R_int = 0.030
7377 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.034	2 restraints
wR(F²) = 0.092	H atoms treated by a mixture of independent and constrained refinement
S = 1.03	Δρ_max = 0.17 e Å⁻³
1613 reflections	Δρ_min = −0.14 e Å⁻³
133 parameters

Special details top

Experimental. Absorption correction: CrysAlisPro, Oxford Diffraction Ltd., Version 1.171.34.44 (release 25-10-2010 CrysAlis171 .NET) (compiled Oct 25 2010,18:11:34) Empirical absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm.

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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
O1	0.41353 (5)	−0.0910 (2)	1.01696 (7)	0.0378 (3)
N3	0.47943 (7)	−0.4111 (3)	0.84565 (10)	0.0398 (3)
H31	0.5197 (9)	−0.283 (4)	0.8730 (13)	0.048*
H32	0.4789 (10)	−0.550 (4)	0.9007 (12)	0.048*
N1	0.32531 (6)	0.0899 (3)	0.85723 (8)	0.0315 (3)
N4	0.41310 (6)	−0.2253 (2)	0.83245 (8)	0.0301 (3)
N2	0.31212 (6)	0.0442 (3)	0.74333 (9)	0.0376 (3)
C1	0.38691 (7)	−0.0749 (3)	0.91540 (10)	0.0290 (3)
C5	0.14844 (8)	0.0222 (3)	0.81353 (11)	0.0368 (3)
H5	0.1579	0.0711	0.743	0.044*
C4	0.20132 (7)	0.1088 (3)	0.91021 (11)	0.0322 (3)
C6	0.08204 (8)	−0.1351 (4)	0.81894 (12)	0.0404 (3)
H6	0.0465	−0.1967	0.7523	0.049*
C7	0.06730 (8)	−0.2024 (4)	0.92066 (13)	0.0448 (4)
H7	0.0215	−0.3082	0.9243	0.054*
C9	0.18659 (8)	0.0385 (4)	1.01228 (12)	0.0417 (3)
H9	0.2225	0.0957	1.0791	0.05*
C2	0.36666 (7)	−0.1467 (3)	0.73250 (10)	0.0349 (3)
H2	0.3732	−0.2221	0.6629	0.042*
C3	0.27350 (7)	0.2839 (3)	0.90400 (12)	0.0384 (3)
H3A	0.2596	0.4788	0.8578	0.046*
H3B	0.3003	0.3534	0.9799	0.046*
C8	0.11940 (9)	−0.1154 (4)	1.01708 (13)	0.0492 (4)
H8	0.1093	−0.161	1.0874	0.059*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0376 (5)	0.0452 (6)	0.0301 (5)	−0.0017 (4)	0.0073 (4)	0.0004 (4)
N3	0.0338 (6)	0.0376 (7)	0.0490 (7)	0.0064 (5)	0.0116 (5)	0.0002 (5)
N1	0.0302 (5)	0.0293 (6)	0.0356 (6)	−0.0001 (4)	0.0094 (4)	0.0003 (4)
N4	0.0291 (5)	0.0287 (6)	0.0338 (5)	−0.0001 (4)	0.0102 (4)	−0.0002 (4)
N2	0.0363 (6)	0.0427 (7)	0.0332 (6)	0.0007 (5)	0.0070 (5)	0.0045 (5)
C1	0.0293 (6)	0.0255 (6)	0.0336 (6)	−0.0050 (5)	0.0101 (5)	0.0009 (5)
C5	0.0363 (7)	0.0378 (7)	0.0369 (7)	0.0016 (6)	0.0101 (5)	0.0006 (6)
C4	0.0308 (6)	0.0256 (7)	0.0406 (7)	0.0052 (5)	0.0093 (5)	−0.0033 (5)
C6	0.0330 (7)	0.0420 (8)	0.0446 (8)	−0.0002 (6)	0.0060 (6)	−0.0033 (6)
C7	0.0363 (7)	0.0423 (8)	0.0592 (9)	−0.0018 (6)	0.0181 (6)	0.0035 (7)
C9	0.0394 (7)	0.0463 (8)	0.0379 (7)	0.0050 (6)	0.0065 (6)	−0.0040 (6)
C2	0.0345 (7)	0.0402 (8)	0.0310 (6)	−0.0022 (6)	0.0097 (5)	−0.0003 (5)
C3	0.0345 (7)	0.0289 (7)	0.0533 (8)	0.0005 (5)	0.0136 (6)	−0.0073 (6)
C8	0.0507 (9)	0.0584 (10)	0.0428 (8)	0.0025 (7)	0.0197 (7)	0.0076 (7)

Geometric parameters (Å, º) top

O1—C1	1.2335 (15)	C4—C9	1.383 (2)
N3—N4	1.4040 (15)	C4—C3	1.5138 (18)
N3—H31	0.900 (14)	C6—C7	1.377 (2)
N3—H32	0.895 (14)	C6—H6	0.95
N1—C1	1.3577 (17)	C7—C8	1.378 (2)
N1—N2	1.3840 (15)	C7—H7	0.95
N1—C3	1.4592 (16)	C9—C8	1.388 (2)
N4—C2	1.3561 (17)	C9—H9	0.95
N4—C1	1.3803 (16)	C2—H2	0.95
N2—C2	1.2993 (18)	C3—H3A	0.99
C5—C6	1.384 (2)	C3—H3B	0.99
C5—C4	1.3861 (19)	C8—H8	0.95
C5—H5	0.95

N4—N3—H31	107.9 (11)	C7—C6—H6	119.9
N4—N3—H32	106.2 (11)	C5—C6—H6	119.9
H31—N3—H32	104.7 (15)	C6—C7—C8	119.63 (13)
C1—N1—N2	112.77 (10)	C6—C7—H7	120.2
C1—N1—C3	126.43 (11)	C8—C7—H7	120.2
N2—N1—C3	120.72 (10)	C4—C9—C8	120.05 (13)
C2—N4—C1	108.65 (10)	C4—C9—H9	120
C2—N4—N3	124.24 (11)	C8—C9—H9	120
C1—N4—N3	126.97 (11)	N2—C2—N4	111.85 (11)
C2—N2—N1	103.95 (10)	N2—C2—H2	124.1
O1—C1—N1	129.42 (12)	N4—C2—H2	124.1
O1—C1—N4	127.80 (12)	N1—C3—C4	113.40 (11)
N1—C1—N4	102.77 (10)	N1—C3—H3A	108.9
C6—C5—C4	120.48 (12)	C4—C3—H3A	108.9
C6—C5—H5	119.8	N1—C3—H3B	108.9
C4—C5—H5	119.8	C4—C3—H3B	108.9
C9—C4—C5	119.16 (13)	H3A—C3—H3B	107.7
C9—C4—C3	120.48 (12)	C7—C8—C9	120.47 (13)
C5—C4—C3	120.35 (12)	C7—C8—H8	119.8
C7—C6—C5	120.20 (13)	C9—C8—H8	119.8

C1—N1—N2—C2	−0.71 (14)	C5—C6—C7—C8	−0.7 (2)
C3—N1—N2—C2	−177.58 (11)	C5—C4—C9—C8	−0.3 (2)
N2—N1—C1—O1	−178.86 (12)	C3—C4—C9—C8	178.48 (13)
C3—N1—C1—O1	−2.2 (2)	N1—N2—C2—N4	0.32 (14)
N2—N1—C1—N4	0.78 (13)	C1—N4—C2—N2	0.15 (15)
C3—N1—C1—N4	177.44 (11)	N3—N4—C2—N2	−175.76 (12)
C2—N4—C1—O1	179.10 (12)	C1—N1—C3—C4	−97.82 (15)
N3—N4—C1—O1	−5.1 (2)	N2—N1—C3—C4	78.60 (15)
C2—N4—C1—N1	−0.55 (13)	C9—C4—C3—N1	114.42 (14)
N3—N4—C1—N1	175.21 (11)	C5—C4—C3—N1	−66.81 (16)
C6—C5—C4—C9	−0.6 (2)	C6—C7—C8—C9	−0.2 (2)
C6—C5—C4—C3	−179.35 (12)	C4—C9—C8—C7	0.7 (2)
C4—C5—C6—C7	1.1 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N3—H32···O1ⁱ	0.90 (1)	2.47 (2)	3.0583 (15)	124 (1)
N3—H31···O1ⁱⁱ	0.90 (1)	2.22 (2)	3.0701 (16)	156 (2)
C2—H2···O1ⁱⁱⁱ	0.95	2.24	3.181 (2)	168

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N3—H32···O1ⁱ	0.895 (14)	2.471 (16)	3.0583 (15)	123.6 (13)
N3—H31···O1ⁱⁱ	0.900 (14)	2.224 (15)	3.0701 (16)	156.2 (15)
C2—H2···O1ⁱⁱⁱ	0.950	2.244	3.181 (2)	168.4

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

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Volume 70| Part 10| October 2014| Pages o1083-o1084

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