5-Pentyl-1H-tetra­zole

Rieth, T.; Schollmeyer, D.; Detert, H.

doi:10.1107/S1600536810052244

organic compounds

CRYSTALLOGRAPHIC
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ISSN: 2056-9890

Volume 67| Part 1| January 2011| Page o156

https://doi.org/10.1107/S1600536810052244

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5-Pentyl-1H-tetrazole

Thorsten Rieth,^a Dieter Schollmeyer ^a and Heiner Detert ^a ^*

^aUniversity Mainz, Duesbergweg 10-14, 55099 Mainz, Germany
^*Correspondence e-mail: detert@uni-mainz.de

(Received 9 December 2010; accepted 13 December 2010; online 18 December 2010)

The title compound C₆H₁₂N₄, is one of a few known tetrazoles with an alkyl chain in the 5-position. The asymmetric unit contains two independent molecules. The molecules are linked by N—H⋯N interactions into chains with graph-set notation D(2) and C₂²(8) along [010]. The two independent molecules form a layered structure, the layers being composed of interdigitating strands of alternatingly oriented and nearly identical molecules.

Related literature

For synthetic methods see: Mihina & Herbst (1950 ); Steven et al. (1993 ); Detert & Schollmeyer (1999 ); Sugiono & Detert (2001 ); Glang et al. (2008 ); Borchmann et al. (2010 ). For the properties of tetrazole, see: Huisgen et al. (1960a ,b , 1961 ); Singh (1980 ); Pernice et al. (1988 ); Huff et al. (1996 ). For graph-set notation, see: Bernstein et al. (1995 ).

Experimental

Crystal data

C₆H₁₂N₄
M_r = 140.20
Triclinic, $[P \overline 1]$
a = 8.7812 (14) Å
b = 9.6770 (12) Å
c = 11.614 (2) Å
α = 93.136 (10)°
β = 112.059 (9)°
γ = 116.389 (7)°
V = 789.6 (2) Å³
Z = 4
Cu Kα radiation
μ = 0.63 mm⁻¹
T = 193 K
0.50 × 0.40 × 0.30 mm

Data collection

Enraf–Nonius CAD-4 diffractometer
3182 measured reflections
2991 independent reflections
2764 reflections with I > 2σ(I)
R_int = 0.070
3 standard reflections every 60 min intensity decay: 2%

Refinement

R[F² > 2σ(F²)] = 0.040
wR(F²) = 0.109
S = 1.04
2991 reflections
184 parameters
H-atom parameters constrained
Δρ_max = 0.24 e Å⁻³
Δρ_min = −0.20 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1A—H1A⋯N4B	0.96	1.82	2.7773 (14)	175
N1B—H1B⋯N4Aⁱ	0.95	1.84	2.7779 (14)	170
Symmetry code: (i) x, y+1, z.

Data collection: CAD-4 Software (Enraf–Nonius, 1989 ); cell refinement: CAD-4 Software; data reduction: CORINC (Dräger & Gattow, 1971 ); program(s) used to solve structure: SIR97 (Altomare et al., 1999 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ); molecular graphics: PLATON (Spek, 2009 ); software used to prepare material for publication: PLATON.

Supporting information

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S1600536810052244/bx2337sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810052244/bx2337Isup2.hkl

checkCIF report

Comment top

The title compound (I), is formed by the addition of triethylammonium azide to capronitrile in refluxing toluene and acidic work-up. In the crystal, molecules are linked by N— H··· N interactions into chains with graph-set notation D(2) a C²₂(8) along [010] (Bernstein et al., 1995), Table 1. Both molecules of the title compound have very similar geometries. The heterocycles and alkyl chains are coplanar with the molecules A oriented to the opposite site of the molecules B. These strands form layers via interdigitation of the alkyl chains.

Related literature top

For synthetic methods see: Mihina & Herbst (1950); Steven et al. (1993); Detert & Schollmeyer (1999); Sugiono & Detert (2001); Glang et al. (2008); Borchmann et al. (2010). For the properties of tetrazole, see: Huisgen et al. (1960a,b, 1961); Singh (1980); Pernice et al. (1988);Huff et al. (1996). For graph-set notation, see: Bernstein et al. (1995).

Experimental top

The title compound was prepared as follows: Triethyl ammonium chloride (8.95 g, 0.06 mol) and sodium azide (3.90 g, 0.06 mol) were added to a solution of hexanoic acid nitrile (4.36 g, 0.045 mol) in toluene (35 ml) and the mixture was stirred under reflux for 72 h. The mixture was filtered, the solvent evaporated and the residue dissolved in water. Hydrochloric acid (6M, 15 ml) was added and the product was extracted with ether/petroleum ether (1/1, 3*30 ml). The cooled organic solutions were dried with sodium sulfate. The solvents were evaporated and the residue crystallized upon standing at ambient temperature within 5 days. Recrystallization from toluene yielded 5-pentyltetrazole in 78% yield as colorless needles.

Structure description top

For synthetic methods see: Mihina & Herbst (1950); Steven et al. (1993); Detert & Schollmeyer (1999); Sugiono & Detert (2001); Glang et al. (2008); Borchmann et al. (2010). For the properties of tetrazole, see: Huisgen et al. (1960a,b, 1961); Singh (1980); Pernice et al. (1988);Huff et al. (1996). For graph-set notation, see: Bernstein et al. (1995).

Computing details top

Data collection: CAD-4 Software (Enraf–Nonius, 1989); cell refinement: CAD-4 Software (Enraf–Nonius, 1989); data reduction: CORINC (Dräger & Gattow, 1971); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: PLATON (Spek, 2009).

Figures top

Fig. 1. View of compound I. Displacement ellipsoids are drawn at the 50% probability level.

5-pentyl-1H-tetrazole top

Crystal data top

C₆H₁₂N₄	Z = 4
M_r = 140.20	F(000) = 304
Triclinic, P1	D_x = 1.179 Mg m⁻³
Hall symbol: -P 1	Melting point: 315 K
a = 8.7812 (14) Å	Cu Kα radiation, λ = 1.54178 Å
b = 9.6770 (12) Å	Cell parameters from 25 reflections
c = 11.614 (2) Å	θ = 65–69°
α = 93.136 (10)°	µ = 0.63 mm⁻¹
β = 112.059 (9)°	T = 193 K
γ = 116.389 (7)°	Block, colourless
V = 789.6 (2) Å³	0.50 × 0.40 × 0.30 mm

Data collection top

Enraf–Nonius CAD-4 diffractometer	R_int = 0.070
Radiation source: rotating anode	θ_max = 70.0°, θ_min = 4.3°
Graphite monochromator	h = −10→9
ω/2θ scans	k = 0→11
3182 measured reflections	l = −14→14
2991 independent reflections	3 standard reflections every 60 min
2764 reflections with I > 2σ(I)	intensity decay: 2%

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)] = 0.040	H-atom parameters constrained
wR(F²) = 0.109	w = 1/[σ²(F_o²) + (0.0611P)² + 0.1618P] where P = (F_o² + 2F_c²)/3
S = 1.04	(Δ/σ)_max < 0.001
2991 reflections	Δρ_max = 0.24 e Å⁻³
184 parameters	Δρ_min = −0.20 e Å⁻³
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0088 (12)

Crystal data top

C₆H₁₂N₄	γ = 116.389 (7)°
M_r = 140.20	V = 789.6 (2) Å³
Triclinic, P1	Z = 4
a = 8.7812 (14) Å	Cu Kα radiation
b = 9.6770 (12) Å	µ = 0.63 mm⁻¹
c = 11.614 (2) Å	T = 193 K
α = 93.136 (10)°	0.50 × 0.40 × 0.30 mm
β = 112.059 (9)°

Data collection top

Enraf–Nonius CAD-4 diffractometer	R_int = 0.070
3182 measured reflections	3 standard reflections every 60 min
2991 independent reflections	intensity decay: 2%
2764 reflections with I > 2σ(I)

Refinement top

R[F² > 2σ(F²)] = 0.040	0 restraints
wR(F²) = 0.109	H-atom parameters constrained
S = 1.04	Δρ_max = 0.24 e Å⁻³
2991 reflections	Δρ_min = −0.20 e Å⁻³
184 parameters

Special details top

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 (Å²) top

	x	y	z	U_iso*/U_eq
N1A	0.76292 (14)	0.44445 (11)	0.33040 (10)	0.0321 (2)
H1A	0.7628	0.5432	0.3397	0.038*
N2A	0.77322 (17)	0.38035 (13)	0.22933 (10)	0.0392 (3)
N3A	0.77338 (17)	0.25012 (13)	0.24908 (11)	0.0413 (3)
N4A	0.76329 (16)	0.22891 (12)	0.36157 (10)	0.0358 (3)
C5A	0.75588 (16)	0.35102 (13)	0.41070 (11)	0.0286 (3)
C6A	0.74035 (18)	0.38071 (13)	0.53191 (11)	0.0321 (3)
H6A	0.6195	0.3797	0.5105	0.039*
H6B	0.8458	0.4884	0.5875	0.039*
C7A	0.74667 (18)	0.25697 (14)	0.60683 (12)	0.0336 (3)
H7A	0.6359	0.1501	0.5540	0.040*
H7B	0.8633	0.2525	0.6233	0.040*
C8A	0.74449 (18)	0.29643 (15)	0.73469 (12)	0.0360 (3)
H8A	0.6351	0.3123	0.7186	0.043*
H8B	0.8619	0.3983	0.7905	0.043*
C9A	0.7308 (2)	0.16675 (18)	0.80548 (14)	0.0441 (3)
H9A	0.6116	0.0655	0.7507	0.053*
H9B	0.8383	0.1489	0.8197	0.053*
C10A	0.7338 (3)	0.2091 (2)	0.93461 (16)	0.0607 (4)
H10A	0.7183	0.1198	0.9740	0.091*
H10B	0.6298	0.2299	0.9215	0.091*
H10C	0.8555	0.3050	0.9916	0.091*
N1B	0.77122 (14)	0.95284 (11)	0.40731 (9)	0.0305 (2)
H1B	0.7639	1.0469	0.3995	0.037*
N2B	0.74619 (15)	0.88499 (12)	0.50153 (10)	0.0350 (3)
N3B	0.74529 (16)	0.75189 (12)	0.47932 (10)	0.0364 (3)
N4B	0.76875 (15)	0.73261 (12)	0.37130 (10)	0.0336 (2)
C5B	0.78464 (16)	0.85919 (13)	0.32751 (11)	0.0288 (3)
C6B	0.81748 (19)	0.89627 (13)	0.21354 (12)	0.0359 (3)
H6C	0.9558	0.9640	0.2423	0.043*
H6D	0.7569	0.9590	0.1766	0.043*
C7B	0.74053 (18)	0.74860 (13)	0.10847 (11)	0.0326 (3)
H7C	0.8051	0.6880	0.1436	0.039*
H7D	0.6030	0.6784	0.0813	0.039*
C8B	0.77032 (18)	0.79245 (14)	−0.00809 (11)	0.0341 (3)
H8C	0.7002	0.8484	−0.0453	0.041*
H8D	0.9071	0.8678	0.0205	0.041*
C9B	0.70495 (19)	0.64908 (15)	−0.11205 (12)	0.0380 (3)
H9C	0.5680	0.5737	−0.1411	0.046*
H9D	0.7749	0.5930	−0.0751	0.046*
C10B	0.7361 (2)	0.69521 (18)	−0.22777 (13)	0.0501 (4)
H10D	0.6736	0.5983	−0.2974	0.075*
H10E	0.8727	0.7536	−0.2030	0.075*
H10F	0.6822	0.7635	−0.2575	0.075*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N1A	0.0489 (6)	0.0245 (5)	0.0357 (5)	0.0239 (4)	0.0240 (5)	0.0118 (4)
N2A	0.0627 (7)	0.0336 (6)	0.0384 (6)	0.0314 (5)	0.0295 (5)	0.0145 (4)
N3A	0.0686 (7)	0.0333 (6)	0.0397 (6)	0.0336 (5)	0.0308 (6)	0.0135 (5)
N4A	0.0564 (6)	0.0268 (5)	0.0379 (6)	0.0269 (5)	0.0264 (5)	0.0118 (4)
C5A	0.0357 (6)	0.0209 (5)	0.0337 (6)	0.0163 (5)	0.0171 (5)	0.0077 (4)
C6A	0.0446 (6)	0.0263 (6)	0.0350 (6)	0.0218 (5)	0.0219 (5)	0.0094 (5)
C7A	0.0440 (7)	0.0288 (6)	0.0360 (6)	0.0214 (5)	0.0214 (5)	0.0112 (5)
C8A	0.0426 (7)	0.0348 (6)	0.0348 (6)	0.0211 (5)	0.0193 (5)	0.0100 (5)
C9A	0.0566 (8)	0.0519 (8)	0.0428 (7)	0.0358 (7)	0.0283 (6)	0.0228 (6)
C10A	0.0868 (12)	0.0807 (12)	0.0495 (9)	0.0573 (10)	0.0426 (9)	0.0353 (8)
N1B	0.0454 (6)	0.0229 (5)	0.0326 (5)	0.0217 (4)	0.0203 (4)	0.0098 (4)
N2B	0.0511 (6)	0.0294 (5)	0.0353 (5)	0.0242 (5)	0.0242 (5)	0.0116 (4)
N3B	0.0544 (6)	0.0303 (5)	0.0370 (5)	0.0255 (5)	0.0263 (5)	0.0151 (4)
N4B	0.0520 (6)	0.0262 (5)	0.0362 (5)	0.0250 (5)	0.0256 (5)	0.0133 (4)
C5B	0.0386 (6)	0.0206 (5)	0.0312 (6)	0.0168 (5)	0.0169 (5)	0.0074 (4)
C6B	0.0554 (7)	0.0235 (6)	0.0359 (6)	0.0205 (5)	0.0260 (6)	0.0118 (5)
C7B	0.0440 (7)	0.0240 (6)	0.0350 (6)	0.0174 (5)	0.0220 (5)	0.0094 (5)
C8B	0.0457 (7)	0.0276 (6)	0.0339 (6)	0.0194 (5)	0.0206 (5)	0.0117 (5)
C9B	0.0507 (7)	0.0322 (6)	0.0347 (6)	0.0208 (6)	0.0224 (6)	0.0097 (5)
C10B	0.0734 (10)	0.0466 (8)	0.0388 (7)	0.0305 (7)	0.0324 (7)	0.0150 (6)

Geometric parameters (Å, º) top

N1A—C5A	1.3330 (15)	N1B—C5B	1.3339 (15)
N1A—N2A	1.3494 (14)	N1B—N2B	1.3446 (14)
N1A—H1A	0.9564	N1B—H1B	0.9474
N2A—N3A	1.2937 (14)	N2B—N3B	1.2956 (14)
N3A—N4A	1.3628 (15)	N3B—N4B	1.3616 (14)
N4A—C5A	1.3223 (14)	N4B—C5B	1.3222 (14)
C5A—C6A	1.4892 (16)	C5B—C6B	1.4868 (16)
C6A—C7A	1.5267 (16)	C6B—C7B	1.5228 (16)
C6A—H6A	0.9900	C6B—H6C	0.9900
C6A—H6B	0.9900	C6B—H6D	0.9900
C7A—C8A	1.5222 (16)	C7B—C8B	1.5203 (16)
C7A—H7A	0.9900	C7B—H7C	0.9900
C7A—H7B	0.9900	C7B—H7D	0.9900
C8A—C9A	1.5226 (18)	C8B—C9B	1.5167 (17)
C8A—H8A	0.9900	C8B—H8C	0.9900
C8A—H8B	0.9900	C8B—H8D	0.9900
C9A—C10A	1.520 (2)	C9B—C10B	1.5212 (17)
C9A—H9A	0.9900	C9B—H9C	0.9900
C9A—H9B	0.9900	C9B—H9D	0.9900
C10A—H10A	0.9800	C10B—H10D	0.9800
C10A—H10B	0.9800	C10B—H10E	0.9800
C10A—H10C	0.9800	C10B—H10F	0.9800

C5A—N1A—N2A	109.67 (9)	C5B—N1B—N2B	109.65 (9)
C5A—N1A—H1A	127.6	C5B—N1B—H1B	129.2
N2A—N1A—H1A	122.7	N2B—N1B—H1B	120.8
N3A—N2A—N1A	106.07 (10)	N3B—N2B—N1B	106.22 (9)
N2A—N3A—N4A	110.18 (10)	N2B—N3B—N4B	110.06 (9)
C5A—N4A—N3A	106.84 (9)	C5B—N4B—N3B	106.84 (9)
N4A—C5A—N1A	107.23 (10)	N4B—C5B—N1B	107.23 (10)
N4A—C5A—C6A	127.37 (10)	N4B—C5B—C6B	127.50 (10)
N1A—C5A—C6A	125.40 (10)	N1B—C5B—C6B	125.25 (10)
C5A—C6A—C7A	112.98 (9)	C5B—C6B—C7B	113.84 (9)
C5A—C6A—H6A	109.0	C5B—C6B—H6C	108.8
C7A—C6A—H6A	109.0	C7B—C6B—H6C	108.8
C5A—C6A—H6B	109.0	C5B—C6B—H6D	108.8
C7A—C6A—H6B	109.0	C7B—C6B—H6D	108.8
H6A—C6A—H6B	107.8	H6C—C6B—H6D	107.7
C8A—C7A—C6A	111.95 (10)	C8B—C7B—C6B	111.84 (10)
C8A—C7A—H7A	109.2	C8B—C7B—H7C	109.2
C6A—C7A—H7A	109.2	C6B—C7B—H7C	109.2
C8A—C7A—H7B	109.2	C8B—C7B—H7D	109.2
C6A—C7A—H7B	109.2	C6B—C7B—H7D	109.2
H7A—C7A—H7B	107.9	H7C—C7B—H7D	107.9
C7A—C8A—C9A	113.17 (11)	C9B—C8B—C7B	113.44 (10)
C7A—C8A—H8A	108.9	C9B—C8B—H8C	108.9
C9A—C8A—H8A	108.9	C7B—C8B—H8C	108.9
C7A—C8A—H8B	108.9	C9B—C8B—H8D	108.9
C9A—C8A—H8B	108.9	C7B—C8B—H8D	108.9
H8A—C8A—H8B	107.8	H8C—C8B—H8D	107.7
C10A—C9A—C8A	112.79 (12)	C8B—C9B—C10B	112.71 (11)
C10A—C9A—H9A	109.0	C8B—C9B—H9C	109.0
C8A—C9A—H9A	109.0	C10B—C9B—H9C	109.0
C10A—C9A—H9B	109.0	C8B—C9B—H9D	109.0
C8A—C9A—H9B	109.0	C10B—C9B—H9D	109.0
H9A—C9A—H9B	107.8	H9C—C9B—H9D	107.8
C9A—C10A—H10A	109.5	C9B—C10B—H10D	109.5
C9A—C10A—H10B	109.5	C9B—C10B—H10E	109.5
H10A—C10A—H10B	109.5	H10D—C10B—H10E	109.5
C9A—C10A—H10C	109.5	C9B—C10B—H10F	109.5
H10A—C10A—H10C	109.5	H10D—C10B—H10F	109.5
H10B—C10A—H10C	109.5	H10E—C10B—H10F	109.5

C5A—N1A—N2A—N3A	−0.33 (14)	C5B—N1B—N2B—N3B	0.27 (13)
N1A—N2A—N3A—N4A	0.02 (14)	N1B—N2B—N3B—N4B	−0.24 (13)
N2A—N3A—N4A—C5A	0.30 (15)	N2B—N3B—N4B—C5B	0.13 (14)
N3A—N4A—C5A—N1A	−0.49 (13)	N3B—N4B—C5B—N1B	0.04 (13)
N3A—N4A—C5A—C6A	178.87 (11)	N3B—N4B—C5B—C6B	178.27 (11)
N2A—N1A—C5A—N4A	0.52 (14)	N2B—N1B—C5B—N4B	−0.19 (13)
N2A—N1A—C5A—C6A	−178.86 (11)	N2B—N1B—C5B—C6B	−178.47 (11)
N4A—C5A—C6A—C7A	3.98 (18)	N4B—C5B—C6B—C7B	28.32 (18)
N1A—C5A—C6A—C7A	−176.77 (11)	N1B—C5B—C6B—C7B	−153.76 (12)
C5A—C6A—C7A—C8A	176.01 (10)	C5B—C6B—C7B—C8B	177.66 (10)
C6A—C7A—C8A—C9A	174.26 (11)	C6B—C7B—C8B—C9B	176.94 (11)
C7A—C8A—C9A—C10A	178.51 (12)	C7B—C8B—C9B—C10B	−179.91 (11)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1A—H1A···N4B	0.96	1.82	2.7773 (14)	175
N1B—H1B···N4Aⁱ	0.95	1.84	2.7779 (14)	170

Symmetry code: (i) x, y+1, z.

Experimental details

Crystal data
Chemical formula	C₆H₁₂N₄
M_r	140.20
Crystal system, space group	Triclinic, P1
Temperature (K)	193
a, b, c (Å)	8.7812 (14), 9.6770 (12), 11.614 (2)
α, β, γ (°)	93.136 (10), 112.059 (9), 116.389 (7)
V (Å³)	789.6 (2)
Z	4
Radiation type	Cu Kα
µ (mm⁻¹)	0.63
Crystal size (mm)	0.50 × 0.40 × 0.30

Data collection
Diffractometer	Enraf–Nonius CAD-4
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	3182, 2991, 2764
R_int	0.070
(sin θ/λ)_max (Å⁻¹)	0.609

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.040, 0.109, 1.04
No. of reflections	2991
No. of parameters	184
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.24, −0.20

Computer programs: CAD-4 Software (Enraf–Nonius, 1989), CORINC (Dräger & Gattow, 1971), SIR97 (Altomare et al., 1999), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1A—H1A···N4B	0.96	1.82	2.7773 (14)	175
N1B—H1B···N4Aⁱ	0.95	1.84	2.7779 (14)	170

Symmetry code: (i) x, y+1, z.

References

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