1-(3-Bromo­prop­yl)-4-(2-pyrid­yl)-1H-1,2,3-triazole

Crowley, J.D.; Bandeen, P.H.; Hanton, L.R.

doi:10.1107/S1600536809012148

organic compounds

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ISSN: 2056-9890

Volume 65| Part 5| May 2009| Pages o999-o1000

doi:10.1107/S1600536809012148

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1-(3-Bromopropyl)-4-(2-pyridyl)-1H-1,2,3-triazole

James D. Crowley,^a ^* Pauline H. Bandeen ^a and Lyall R. Hanton ^a

^aDepartment of Chemistry, University of Otago, PO Box 56, Dunedin, New Zealand
^*Correspondence e-mail: jcrowley@chemistry.otago.ac.nz

(Received 20 March 2009; accepted 1 April 2009; online 8 April 2009)

In the structure of the title compound, C₁₀H₁₁BrN₄, the plane of the substituted 1,2,3-triazole ring is tilted by 14.84 (10)° with respect to the mean plane of the pyridine ring. The pyridine and closest triazole N atoms adopt an anti arrangement which removes any lone pair–lone pair repulsions between the N atoms. This conformation is further stabilized by weak intermolecular C—H⋯N interactions. There are two molecules in the unit cell, which form a centrosymmetric head-to-tail dimer. The dimers are stabilized through π–π interactions [centroid–centroid distance = 3.733 (4) Å and mean interplanar distance = 3.806 (12) Å] between the substituted 1,2,3-triazole ring and the pyridine rings in adjacent molecules. Each dimer interacts with two neighbouring dimers above and below, forming a slipped stack of dimers through the crystal. The 3-bromopropyl chain sits over the pyridine ring of a neighbouring molecule and the triazole rings of nearby molecules are adjacent.

Related literature

For details of the Cu(I)-catalysed 1,3-cycloaddition of organic azides with terminal alkynes, see: Rostovtsev et al. (2002 ); Tornoe et al. (2002 ); Meldal & Tornoe (2008 ). For applications of pyridyl-functionalized 1,2,3-triazoles, see: Li & Flood (2008 ); Meudtner & Hecht (2008 ); Krivopalov & Shkurko (2005 ); Li et al. (2007 ); Richardson et al. (2008 ). For related structures, see Schweinfurth et al. (2008 ); Obata et al. (2008 ).

Experimental

Crystal data

C₁₀H₁₁BrN₄
M_r = 267.14
Triclinic, $[P \overline 1]$
a = 5.658 (2) Å
b = 9.688 (4) Å
c = 10.191 (4) Å
α = 84.498 (3)°
β = 85.663 (2)°
γ = 83.854 (2)°
V = 551.6 (4) Å³
Z = 2
Mo Kα radiation
μ = 3.70 mm⁻¹
T = 90 K
0.53 × 0.23 × 0.11 mm

Data collection

Bruker APEXII CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2004 ) T_min = 0.358, T_max = 0.66
8776 measured reflections
1879 independent reflections
1759 reflections with I > 2σ(I)
R_int = 0.043

Refinement

R[F² > 2σ(F²)] = 0.027
wR(F²) = 0.071
S = 0.97
1879 reflections
136 parameters
H-atom parameters constrained
Δρ_max = 0.64 e Å⁻³
Δρ_min = −0.61 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C7—H7⋯N2ⁱ	0.93	2.62	3.449 (4)	149
C10—H10B⋯N1ⁱⁱ	0.97	2.51	3.450 (4)	164
Symmetry codes: (i) x+1, y, z; (ii) -x+2, -y, -z+1.

Data collection: APEX2 (Bruker, 2004); cell refinement: APEX2 and SAINT (Bruker, 2004); 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 (Farrugia, 1997 ) and Mercury (Bruno et al., 2002 ); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and enCIFer (Allen et al., 2004 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809012148/fj2204sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809012148/fj2204Isup2.hkl

checkCIF report

Comment top

The Cu(I)-catalyzed 1,3-cycloaddition of organic azides with terminal alkynes (the CuAAC reaction) (Rostovtsev et al. 2002; Tornoe et al. 2002) has quickly become an indispensable tool for functional molecule synthesis and renewed interest in the chemistry of functionalized 1,2,3-triazoles (Meldal & Tornoe, 2008). Because they are readily synthesized using the CuAAC reaction, pyridyl functionalized 1,2,3-triazoles have begun attracting significant attention in a range of areas including anion recognition (Li & Flood, 2008), stimuli responsive foldamers (Meudtner & Hecht, 2008), drug discovery (Krivopalov & Shkurko, 2005) and coordination chemistry (Li et al. 2007; Richardson et al., 2008; Schweinfurth et al., 2008; Obata et al., 2008)

The molecular structure of the new triazole compound 1 is shown in Fig. 1. The molecule consists of an essentially co-planar (2-pyridyl) and 1,2,3-triazole units attached to a 3-bromopropyl chain, the plane of the substituted 1,2,3-triazole ring is tilted by 14.84 (10)° with respect to the mean plane of the pyridine ring system. As is commonly observed (Obata et al., 2008; Schweinfurth et al., 2008) N1 in the pyridine ring and N2 of the triazole ring adopt an anti arrangement which removes any lone pair-lone pair repulsions between the nitrogen atoms. Additionally, the anti conformation is stabilized by weak C—H···N interactions. There are two molecules of 1 in the unit cell which form a centrosymmetric head to tail dimer that is stabilized through a π-π interaction [centroid-centroid distance = 3.733 (4) Å, mean interplanar distance 3.806 (12) Å] between the substituted 1,2,3-triazole and the pyridine rings in adjacent molecules. In the extended crystal each dimer interacts with two neighbouring dimers above and below to form slipped stacks of dimers through the crystal. The 3-bromopropyl chain sits over the pyridine ring of the neighbouring molecule and the triazole rings of nearby molecules are adjacent [centroid-centroid distance = 4.691 (4) Å]. Unlike the dimer units, the extended stacks appear not to be stabilized by π-π interactions, the mean interplanar distance between dimers of 1 is 4.060 Å are outside the range normally expected for a π-π interaction. A steric interaction between the bromopropyl chain on one molecule of 1 and the pyridine ring on the adjacent molecule in the next dimer prevents a closer face to face interaction of the aromatic rings in the different dimer units.

Related literature top

For details of the Cu(I)-catalysed 1,3-cycloaddition of organic azides with terminal alkynes, see: Rostovtsev et al. (2002); Tornoe et al. (2002); Meldal & Tornoe (2008). For applications of pyridyl-functionalized 1,2,3-triazoles, see: Li & Flood (2008); Meudtner & Hecht (2008); Krivopalov & Shkurko (2005); Li et al. (2007); Richardson et al. (2008). For related structures, see Schweinfurth et al. (2008); Obata et al. (2008).

Experimental top

The title compound, C₁₀H₁₁BrN₄ (1) was obtained as a by-product during the attempted synthesis of a ditopic propyl bridged bis((2-pyridyl)-1,2,3-triazole) ligand. X-ray quality colourless crystals were obtained by slow evaporation of a petroleum ether solution of 1 but were weakly diffracting.

To a stirred solution of 1,3-dibromopropane (0.301 g, 1.5 mmol, 1.00 eq.) in DMF/H₂O (15 ml, 4:1) was added NaN₃ (0.205 g, 3.1 mmol, 2.05 eq.), Na₂CO₃ (0.13 g, 1.2 mmol, 0.8 eq.), CuSO₄.5H₂O (0.150 g, 0.6 mmol, 0.40 eq.), ascorbic acid (0.210 g, 1.2 mmol, 0.80 eq). 2-Ethynylpyridine (0.323 g, 3.1 mmol, 2.05 eq.) was added and the reaction mixture was stirred at room temperature for 20 h. The resulting suspension was then partitioned between aqueous NH₄OH/edta (1 M, 100 ml) and CH₂Cl₂ (50 ml) and the layers separated. The organic phase was washed with H₂O (100 ml) and brine (100 ml), dried (MgSO₄) and the solvent removed under reduced pressure. Chromatography (gradient CH₂Cl₂/acetone to a ratio 9:1) gave the product as a white solid. Yield: 0.190 g, 47%. Mp 89–91 °C; ¹H NMR (300 MHz, CDCl₃) δ 8.58 (ddd, J = 0.9, J = 1.7, J = 4.9, 1H, H₁), 8.23–8.12 (m, 2H, H_4,5), 7.78 (td, J = 1.8, J = 7.8, 1H, H₃), 7.26–7.21 (m, 1H, H₂), 4.62 (t, J = 6.5, 2H, H₁₀), 3.40 (t, J = 6.2, 2H, H₈), 2.52 (p, J = 6.4, 2H, H₉); ¹³C NMR (75 MHz, CDCl₃) δ: 150.2, 149.5, 148.5, 136.9, 122.9, 122.6, 120.3, 48.3, 32.7, 29.3; I.R. (KBr): ν(cm^-1) 3400–3200 (br), 3116, 3087, 2924, 1701, 1617, 1607, 1598, 1572, 1548, 1473, 1466, 1447, 1421, 1358, 1317, 1287, 1250, 1224, 1204, 1144, 1080, 1048, 983, 969, 891, 855, 844, 826, 786, 744, 708; HRESI-MS (MeOH): m/z = 289.0066 [M+Na]+ (calc. for C₁₀H₁₁⁷⁹BrN₄Na 289.0065 [M+Na]+), 291.0040 [M+Na]+ (calc. for C₁₀H₁₁⁸¹BrN₄Na 291.0044 [M+Na]+; Anal. calcd for C₁₀H₁₁BrN₄(H₂O): C, 44.96; H, 4.15; N, 20.97; Found: C, 45.36; H, 4.24; N, 21.03.

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: APEX2 and SAINT (Bruker, 2004); data reduction: SAINT (Bruker, 2004); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and Mercury (Bruno et al., 2002); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and enCIFer (Allen et al., 2004).

Figures top

	Fig. 1. The molecular structure of compound 1, showing the atom numbering scheme. The thermal displacement ellipsoids are drawn at the 50% probability level.
	Fig. 2. A spacefilling representation of the unit cell of 1 showing the head-to-tail stacking of the molecules.
	Fig. 3. A spacefilling representation of the crystal packing present in 1, showing the slipped stacks of the dimers.

1-(3-Bromopropyl)-4-(2-pyridyl)-1H-1,2,3-triazole top

Crystal data top

C₁₀H₁₁BrN₄	Z = 2
M_r = 267.14	F(000) = 268
Triclinic, P1	D_x = 1.608 Mg m⁻³
Hall symbol: -P 1	Melting point: 362 K
a = 5.658 (2) Å	Mo Kα radiation, λ = 0.71073 Å
b = 9.688 (4) Å	Cell parameters from 5048 reflections
c = 10.191 (4) Å	θ = 3.1–33.3°
α = 84.498 (3)°	µ = 3.70 mm⁻¹
β = 85.663 (2)°	T = 90 K
γ = 83.854 (2)°	Irregular, colourless
V = 551.6 (4) Å³	0.53 × 0.23 × 0.11 mm

Data collection top

Bruker APEXII CCD area-detector diffractometer	1879 independent reflections
Radiation source: fine-focus sealed tube	1759 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.043
ϕ and ω scans	θ_max = 25.0°, θ_min = 4.0°
Absorption correction: multi-scan (SADABS; Bruker, 2004)	h = −6→6
T_min = 0.358, T_max = 0.66	k = −11→11
8776 measured reflections	l = −12→12

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)] = 0.027	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.071	H-atom parameters constrained
S = 0.97	w = 1/[σ²(F_o²) + (0.0372P)² + 0.5592P] where P = (F_o² + 2F_c²)/3
1879 reflections	(Δ/σ)_max = 0.001
136 parameters	Δρ_max = 0.64 e Å⁻³
0 restraints	Δρ_min = −0.61 e Å⁻³

Crystal data top

C₁₀H₁₁BrN₄	γ = 83.854 (2)°
M_r = 267.14	V = 551.6 (4) Å³
Triclinic, P1	Z = 2
a = 5.658 (2) Å	Mo Kα radiation
b = 9.688 (4) Å	µ = 3.70 mm⁻¹
c = 10.191 (4) Å	T = 90 K
α = 84.498 (3)°	0.53 × 0.23 × 0.11 mm
β = 85.663 (2)°

Data collection top

Bruker APEXII CCD area-detector diffractometer	1879 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2004)	1759 reflections with I > 2σ(I)
T_min = 0.358, T_max = 0.66	R_int = 0.043
8776 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.027	0 restraints
wR(F²) = 0.071	H-atom parameters constrained
S = 0.97	Δρ_max = 0.64 e Å⁻³
1879 reflections	Δρ_min = −0.61 e Å⁻³
136 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
Br1	0.84285 (5)	−0.19395 (3)	0.97535 (3)	0.03839 (13)
N3	0.3211 (3)	0.1602 (2)	0.6731 (2)	0.0243 (4)
C6	0.4287 (4)	0.2879 (2)	0.4946 (2)	0.0177 (5)
N2	0.2396 (4)	0.2401 (2)	0.5713 (2)	0.0236 (4)
N1	0.6005 (4)	0.4000 (2)	0.2965 (2)	0.0230 (4)
N4	0.5611 (3)	0.15753 (19)	0.66118 (19)	0.0188 (4)
C5	0.3999 (4)	0.3838 (2)	0.3747 (2)	0.0179 (5)
C7	0.6350 (4)	0.2341 (2)	0.5518 (2)	0.0185 (5)
H7	0.7908	0.2476	0.5215	0.022*
C4	0.1805 (4)	0.4545 (2)	0.3468 (2)	0.0216 (5)
H4	0.0447	0.4385	0.4010	0.026*
C8	0.7073 (4)	0.0790 (2)	0.7608 (2)	0.0212 (5)
H8A	0.6075	0.0576	0.8403	0.025*
H8B	0.8267	0.1360	0.7832	0.025*
C2	0.3717 (5)	0.5674 (2)	0.1552 (2)	0.0244 (5)
H2	0.3677	0.6302	0.0802	0.029*
C1	0.5814 (4)	0.4892 (2)	0.1884 (2)	0.0249 (5)
H1	0.7170	0.4993	0.1322	0.030*
C9	0.8298 (5)	−0.0555 (3)	0.7124 (2)	0.0291 (6)
H9A	0.7101	−0.1168	0.7002	0.035*
H9B	0.9133	−0.0349	0.6273	0.035*
C3	0.1681 (4)	0.5495 (2)	0.2364 (2)	0.0242 (5)
H3	0.0245	0.6008	0.2172	0.029*
C10	1.0035 (5)	−0.1294 (3)	0.8062 (3)	0.0309 (6)
H10A	1.1188	−0.0667	0.8222	0.037*
H10B	1.0890	−0.2087	0.7663	0.037*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br1	0.04089 (19)	0.03674 (19)	0.03195 (18)	0.00206 (12)	0.00069 (13)	0.01657 (12)
N3	0.0180 (10)	0.0273 (11)	0.0260 (11)	−0.0011 (8)	−0.0002 (9)	0.0033 (9)
C6	0.0187 (11)	0.0154 (10)	0.0191 (11)	−0.0011 (9)	−0.0003 (9)	−0.0032 (9)
N2	0.0191 (10)	0.0265 (10)	0.0241 (11)	−0.0024 (8)	−0.0010 (8)	0.0032 (9)
N1	0.0214 (10)	0.0240 (10)	0.0227 (10)	−0.0008 (8)	0.0001 (9)	−0.0013 (8)
N4	0.0171 (9)	0.0191 (9)	0.0194 (10)	0.0001 (8)	−0.0017 (8)	0.0001 (8)
C5	0.0187 (11)	0.0152 (10)	0.0200 (11)	−0.0024 (9)	−0.0012 (9)	−0.0028 (9)
C7	0.0159 (11)	0.0181 (10)	0.0212 (11)	−0.0013 (9)	−0.0002 (9)	−0.0014 (9)
C4	0.0170 (11)	0.0229 (11)	0.0246 (12)	−0.0011 (9)	−0.0006 (10)	−0.0021 (10)
C8	0.0240 (12)	0.0200 (11)	0.0187 (11)	0.0020 (9)	−0.0037 (10)	−0.0007 (9)
C2	0.0344 (14)	0.0183 (11)	0.0208 (12)	−0.0028 (10)	−0.0075 (11)	0.0015 (9)
C1	0.0251 (12)	0.0266 (12)	0.0220 (12)	−0.0039 (10)	0.0024 (10)	0.0015 (10)
C9	0.0424 (15)	0.0230 (12)	0.0198 (12)	0.0072 (11)	−0.0026 (11)	−0.0027 (10)
C3	0.0239 (12)	0.0204 (11)	0.0281 (13)	0.0029 (10)	−0.0067 (11)	−0.0030 (10)
C10	0.0357 (15)	0.0261 (13)	0.0264 (13)	0.0093 (11)	0.0030 (12)	0.0028 (10)

Geometric parameters (Å, º) top

Br1—C10	1.966 (3)	C8—C9	1.516 (3)
N3—N2	1.315 (3)	C8—H8A	0.9700
N3—N4	1.352 (3)	C8—H8B	0.9700
C6—N2	1.371 (3)	C2—C3	1.383 (4)
C6—C7	1.373 (3)	C2—C1	1.384 (4)
C6—C5	1.471 (3)	C2—H2	0.9300
N1—C1	1.337 (3)	C1—H1	0.9300
N1—C5	1.351 (3)	C9—C10	1.501 (4)
N4—C7	1.344 (3)	C9—H9A	0.9700
N4—C8	1.463 (3)	C9—H9B	0.9700
C5—C4	1.388 (3)	C3—H3	0.9300
C7—H7	0.9300	C10—H10A	0.9700
C4—C3	1.384 (3)	C10—H10B	0.9700
C4—H4	0.9300

N2—N3—N4	106.83 (18)	H8A—C8—H8B	107.9
N2—C6—C7	108.4 (2)	C3—C2—C1	118.2 (2)
N2—C6—C5	122.9 (2)	C3—C2—H2	120.9
C7—C6—C5	128.7 (2)	C1—C2—H2	120.9
N3—N2—C6	108.78 (19)	N1—C1—C2	123.8 (2)
C1—N1—C5	117.1 (2)	N1—C1—H1	118.1
C7—N4—N3	111.53 (18)	C2—C1—H1	118.1
C7—N4—C8	127.7 (2)	C10—C9—C8	112.8 (2)
N3—N4—C8	120.73 (19)	C10—C9—H9A	109.0
N1—C5—C4	122.9 (2)	C8—C9—H9A	109.0
N1—C5—C6	115.7 (2)	C10—C9—H9B	109.0
C4—C5—C6	121.4 (2)	C8—C9—H9B	109.0
N4—C7—C6	104.5 (2)	H9A—C9—H9B	107.8
N4—C7—H7	127.8	C2—C3—C4	119.3 (2)
C6—C7—H7	127.8	C2—C3—H3	120.4
C3—C4—C5	118.6 (2)	C4—C3—H3	120.4
C3—C4—H4	120.7	C9—C10—Br1	111.7 (2)
C5—C4—H4	120.7	C9—C10—H10A	109.3
N4—C8—C9	111.80 (19)	Br1—C10—H10A	109.3
N4—C8—H8A	109.3	C9—C10—H10B	109.3
C9—C8—H8A	109.3	Br1—C10—H10B	109.3
N4—C8—H8B	109.3	H10A—C10—H10B	107.9
C9—C8—H8B	109.3

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C7—H7···N2ⁱ	0.93	2.62	3.449 (4)	149
C10—H10B···N1ⁱⁱ	0.97	2.51	3.450 (4)	164

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

Experimental details

Crystal data
Chemical formula	C₁₀H₁₁BrN₄
M_r	267.14
Crystal system, space group	Triclinic, P1
Temperature (K)	90
a, b, c (Å)	5.658 (2), 9.688 (4), 10.191 (4)
α, β, γ (°)	84.498 (3), 85.663 (2), 83.854 (2)
V (Å³)	551.6 (4)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	3.70
Crystal size (mm)	0.53 × 0.23 × 0.11

Data collection
Diffractometer	Bruker APEXII CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2004)
T_min, T_max	0.358, 0.66
No. of measured, independent and observed [I > 2σ(I)] reflections	8776, 1879, 1759
R_int	0.043
(sin θ/λ)_max (Å⁻¹)	0.594

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.027, 0.071, 0.97
No. of reflections	1879
No. of parameters	136
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.64, −0.61

Computer programs: APEX2 (Bruker, 2004), APEX2 and SAINT (Bruker, 2004), SAINT (Bruker, 2004), SIR97 (Altomare et al., 1999), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and Mercury (Bruno et al., 2002), SHELXTL (Sheldrick, 2008) and enCIFer (Allen et al., 2004).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C7—H7···N2ⁱ	0.93	2.62	3.449 (4)	149
C10—H10B···N1ⁱⁱ	0.97	2.51	3.450 (4)	164

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

Acknowledgements

We thank the Chemistry Department, University of Otago, for financial assistance.

References

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