A second ortho­rhom­bic polymorph of 3,5-diphenyl-4H-1,2,4-triazol-4-amine

Abstract

The present crystal structure is the second ortho­rhom­bic polymorph of the title compound, C₁₄H₁₂N₄. Whereas the structure in Pnma with Z′ = 0.5 is already known [Ikemi et al. (2002 ▶). Heterocycl. Commun. 8, 439–442], the present structure crystallizes in the space group Pbca with Z′ = 1. The dihedral angle between the two phenyl rings is 23.5 (4)° and the dihedral angles between central ring and the phenyl rings are 41.0 (3) and 26.3 (5)°. In the 4-amino-1,2,4-trizole fragment, the C=N distances are 1.321 (3) and 1.315 (3) Å, which are much shorter than the C—N distances of 1.367 (3) and 1.357 (3) Å. In the crystal, adjacent mol­ecules are linked by N—H⋯N hydrogen bonds.

Related literature

For 4-amino-1,2,4-triazoles derivatives, see: Beckmann & Brooker (2003 ▶); Collin et al. (2003 ▶). For the other polymorph, see: Ikemi et al. (2002 ▶).

Experimental

Crystal data

• C₁₄H₁₂N₄

• M _r = 236.28

• Orthorhombic,

• a = 7.5521 (9) Å

• b = 11.2309 (14) Å

• c = 28.278 (3) Å

• V = 2398.4 (5) ų

• Z = 8

• Mo Kα radiation

• μ = 0.08 mm⁻¹

• T = 293 K

• 0.30 × 0.28 × 0.25 mm

Data collection

• Bruker SMART CCD diffractometer

• Absorption correction: multi-scan (SADABS; Sheldrick, 2000 ▶) T _min = 0.976, T _max = 0.980

• 9495 measured reflections

• 2307 independent reflections

• 1613 reflections with I > 2σ(I)

• R _int = 0.029

Refinement

• R[F ² > 2σ(F ²)] = 0.056

• wR(F ²) = 0.161

• S = 1.07

• 2307 reflections

• 164 parameters

• H-atom parameters constrained

• Δρ_max = 0.16 e Å⁻³

• Δρ_min = −0.18 e Å⁻³

Data collection: SMART (Bruker, 2000 ▶); cell refinement: SAINT (Bruker, 2000 ▶); 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.

Supplementary Material

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

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

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N4—H4B⋯N2i	0.95	2.17	3.117 (2)	177

Symmetry code: (i) .

supplementary crystallographic information

Comment

The derivatives of 4-amino-1,2,4-triazoles have been extensively investigated in in medicinal chemistry and agricultural chemistry (Collin et al., 2003). They are a type of multidentate ligands in coordination chemistry (Beckmann et al. 2003). Herein, we report the crystal structure of 3,5-diphenyl-4H-1,2,4-triazol-4-amine.

The title compound, C₁₄H₁₂N₄, is a 4-amino-3,5-disubstituted-1,2,4-trizole compound and with a dihedral angle between the two phenyl rings of 23.5 (4) °. In the 4-amino-1,2,4-trizole fragment, the C=N distance is 1.321 (3) and 1.315 (3) Å, which are much shorter than the C—N distances of 1.367 (3) and 1.357 (3) Å. In the crystal, adjacent molecules are linked by N—H···N hydrogen bonds into a one-dimensional chain with N···N distance 3.117 (3) Å. The crystal structure of the title compound is a second orthorhombic polymorph. Whereas the structure in Pnma with Z'=0.5 is already known(Ikemi et al. 2002), the present structure has the space group Pbca with Z'=1.

Experimental

A mixture solution of the benzonitrile (0.103 g, 1.0 mmol), 50% NH₂NH₂.H₂O (3 ml) and ethanol (2 ml) was heated in a 15 ml Teflon-lined autoclave at 100 ° for 3 days, followed by slow cooling (5 ° h-1) to room temperature. The colorless block crystals were collected by filtration washed with water, then dried and collected in 11.9% yield (0.014 g) based on benzonitrile.

Refinement

H atoms bonded to N atoms were located in a difference map with the restraint of N—H = 0.95 Å. Other H atoms were positioned geometrically and refined using a riding model with C—H = 0.93 Å and with U_iso(H) = 1.2 U_iso(C).

Figures

Fig. 1.

Structure of the title compound with 30% thermal ellipsoids.

Fig. 2.

The one-dimensional hydrogen bonding network of the title compound.

Crystal data

C14H12N4	F(000) = 992
Mr = 236.28	Dx = 1.309 Mg m−3
Orthorhombic, Pbca	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2ab	Cell parameters from 1617 reflections
a = 7.5521 (9) Å	θ = 2.9–27.7°
b = 11.2309 (14) Å	µ = 0.08 mm−1
c = 28.278 (3) Å	T = 293 K
V = 2398.4 (5) Å3	Block, colorless
Z = 8	0.30 × 0.28 × 0.25 mm

Data collection

Bruker SMART CCD diffractometer	2307 independent reflections
Radiation source: fine-focus sealed tube	1613 reflections with I > 2σ(I)
graphite	Rint = 0.029
φ and ω scans	θmax = 26.0°, θmin = 2.9°
Absorption correction: multi-scan (SADABS; Sheldrick, 2000)	h = −8→8
Tmin = 0.976, Tmax = 0.980	k = −8→13
9495 measured reflections	l = −34→34

Refinement

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)] = 0.056	H-atom parameters constrained
wR(F2) = 0.161	w = 1/[σ2(Fo2) + (0.075P)2 + 0.3879P] where P = (Fo2 + 2Fc2)/3
S = 1.07	(Δ/σ)max < 0.001
2307 reflections	Δρmax = 0.16 e Å−3
164 parameters	Δρmin = −0.18 e Å−3
0 restraints	Extinction correction: SHELXTL (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0018 (7)

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
C1	0.1186 (4)	0.1019 (2)	0.34391 (9)	0.0903 (8)
H1A	0.1495	0.0470	0.3671	0.108*
C2	0.0906 (5)	0.0634 (3)	0.29855 (10)	0.1183 (11)
H2A	0.1035	−0.0168	0.2912	0.142*
C3	0.0438 (5)	0.1425 (5)	0.26392 (13)	0.1355 (13)
H3A	0.0215	0.1166	0.2333	0.163*
C4	0.0307 (6)	0.2600 (4)	0.27534 (14)	0.1452 (16)
H4A	0.0020	0.3147	0.2519	0.174*
C5	0.0585 (5)	0.2991 (3)	0.32027 (12)	0.1164 (11)
H5A	0.0482	0.3799	0.3270	0.140*
C6	0.1018 (3)	0.2208 (2)	0.35588 (9)	0.0750 (7)
C7	0.1304 (3)	0.26686 (18)	0.40343 (9)	0.0672 (6)
C8	0.1462 (2)	0.28566 (15)	0.48031 (9)	0.0646 (6)
C9	0.1367 (2)	0.26276 (16)	0.53087 (8)	0.0623 (6)
C10	0.0670 (3)	0.35010 (19)	0.56046 (10)	0.0766 (7)
H10A	0.0238	0.4206	0.5476	0.092*
C11	0.0618 (3)	0.3326 (2)	0.60841 (11)	0.0893 (8)
H11A	0.0159	0.3914	0.6280	0.107*
C12	0.1239 (3)	0.2287 (2)	0.62747 (10)	0.0901 (8)
H12A	0.1197	0.2171	0.6600	0.108*
C13	0.1924 (3)	0.1416 (2)	0.59877 (10)	0.0839 (7)
H13A	0.2339	0.0711	0.6120	0.101*
C14	0.1998 (3)	0.15788 (18)	0.55063 (9)	0.0694 (6)
H14A	0.2471	0.0988	0.5313	0.083*
N1	0.1804 (3)	0.37701 (15)	0.41296 (9)	0.0858 (7)
N2	0.1900 (3)	0.38864 (15)	0.46152 (9)	0.0816 (6)
N3	0.1098 (2)	0.20701 (13)	0.44473 (6)	0.0597 (5)
N4	0.0340 (2)	0.09288 (13)	0.44985 (6)	0.0639 (5)
H4B	0.1214	0.0327	0.4533	0.077*
H4C	−0.0467	0.0933	0.4756	0.077*

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
C1	0.109 (2)	0.0712 (17)	0.0906 (18)	−0.0055 (14)	−0.0115 (14)	0.0118 (13)
C2	0.157 (3)	0.103 (2)	0.095 (2)	−0.014 (2)	−0.0136 (18)	0.0066 (18)
C3	0.147 (3)	0.166 (4)	0.094 (2)	0.000 (3)	−0.009 (2)	0.014 (2)
C4	0.180 (4)	0.142 (4)	0.114 (3)	0.052 (3)	0.017 (2)	0.053 (3)
C5	0.143 (3)	0.094 (2)	0.112 (2)	0.0370 (19)	0.033 (2)	0.0354 (19)
C6	0.0566 (13)	0.0589 (13)	0.1096 (18)	0.0088 (10)	0.0127 (11)	0.0270 (13)
C7	0.0547 (13)	0.0442 (12)	0.1026 (17)	0.0067 (9)	0.0109 (10)	0.0087 (11)
C8	0.0410 (11)	0.0299 (10)	0.1228 (18)	−0.0006 (7)	0.0057 (10)	−0.0089 (10)
C9	0.0407 (11)	0.0405 (10)	0.1057 (16)	−0.0069 (8)	0.0007 (9)	−0.0121 (10)
C10	0.0526 (13)	0.0444 (12)	0.133 (2)	−0.0024 (9)	0.0074 (12)	−0.0186 (12)
C11	0.0712 (16)	0.0771 (18)	0.120 (2)	−0.0073 (13)	0.0126 (14)	−0.0343 (16)
C12	0.0805 (18)	0.0828 (18)	0.1069 (19)	−0.0079 (14)	0.0000 (13)	−0.0208 (15)
C13	0.0754 (16)	0.0659 (15)	0.110 (2)	−0.0029 (12)	−0.0134 (13)	−0.0073 (13)
C14	0.0521 (13)	0.0455 (12)	0.1107 (19)	−0.0004 (9)	−0.0064 (11)	−0.0167 (11)
N1	0.0767 (14)	0.0379 (10)	0.143 (2)	−0.0021 (9)	0.0250 (12)	0.0139 (11)
N2	0.0750 (14)	0.0409 (10)	0.1290 (18)	−0.0081 (8)	0.0187 (11)	−0.0036 (10)
N3	0.0452 (9)	0.0324 (8)	0.1015 (13)	0.0009 (6)	0.0045 (8)	0.0037 (8)
N4	0.0606 (11)	0.0310 (8)	0.1000 (13)	−0.0052 (7)	0.0100 (8)	0.0013 (7)

Geometric parameters (Å, °)

C1—C2	1.370 (4)	C8—C9	1.454 (3)
C1—C6	1.383 (3)	C9—C14	1.388 (3)
C1—H1A	0.9300	C9—C10	1.393 (3)
C2—C3	1.368 (5)	C10—C11	1.371 (4)
C2—H2A	0.9300	C10—H10A	0.9300
C3—C4	1.362 (5)	C11—C12	1.368 (4)
C3—H3A	0.9300	C11—H11A	0.9300
C4—C5	1.361 (5)	C12—C13	1.373 (3)
C4—H4A	0.9300	C12—H12A	0.9300
C5—C6	1.377 (3)	C13—C14	1.375 (3)
C5—H5A	0.9300	C13—H13A	0.9300
C6—C7	1.457 (3)	C14—H14A	0.9300
C7—N1	1.321 (3)	N1—N2	1.381 (3)
C7—N3	1.356 (3)	N3—N4	1.411 (2)
C8—N2	1.315 (2)	N4—H4B	0.9499
C8—N3	1.367 (3)	N4—H4C	0.9498
C2—C1—C6	121.3 (3)	C14—C9—C8	121.92 (18)
C2—C1—H1A	119.4	C10—C9—C8	119.0 (2)
C6—C1—H1A	119.4	C11—C10—C9	120.3 (2)
C3—C2—C1	120.4 (3)	C11—C10—H10A	119.9
C3—C2—H2A	119.8	C9—C10—H10A	119.9
C1—C2—H2A	119.8	C12—C11—C10	120.1 (2)
C4—C3—C2	118.6 (4)	C12—C11—H11A	119.9
C4—C3—H3A	120.7	C10—C11—H11A	119.9
C2—C3—H3A	120.7	C11—C12—C13	120.3 (3)
C5—C4—C3	121.5 (3)	C11—C12—H12A	119.9
C5—C4—H4A	119.2	C13—C12—H12A	119.9
C3—C4—H4A	119.2	C12—C13—C14	120.4 (2)
C4—C5—C6	120.9 (3)	C12—C13—H13A	119.8
C4—C5—H5A	119.6	C14—C13—H13A	119.8
C6—C5—H5A	119.6	C13—C14—C9	119.8 (2)
C5—C6—C1	117.4 (3)	C13—C14—H14A	120.1
C5—C6—C7	118.9 (3)	C9—C14—H14A	120.1
C1—C6—C7	123.7 (2)	C7—N1—N2	107.83 (19)
N1—C7—N3	108.7 (2)	C8—N2—N1	107.78 (18)
N1—C7—C6	124.3 (2)	C7—N3—C8	106.89 (17)
N3—C7—C6	126.98 (19)	C7—N3—N4	125.81 (18)
N2—C8—N3	108.8 (2)	C8—N3—N4	126.36 (17)
N2—C8—C9	124.41 (19)	N3—N4—H4B	112.0
N3—C8—C9	126.83 (17)	N3—N4—H4C	109.5
C14—C9—C10	119.1 (2)	H4B—N4—H4C	111.8

Hydrogen-bond geometry (Å, °)

D—H···A	D—H	H···A	D···A	D—H···A
N4—H4B···N2i	0.95	2.17	3.117 (2)	177

Symmetry codes: (i) −x+1/2, y−1/2, z.