Crystal structure of 1-meth­oxy-2,2,2-tris­(pyrazol-1-yl)ethane

Lyubartseva, G.; Parkin, S.; Coleman, M.D.; Mallik, U.P.

doi:10.1107/S1600536814018789

organic compounds

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ISSN: 2056-9890

Volume 70| Part 9| September 2014| Pages o1047-o1048

doi:10.1107/S1600536814018789

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Crystal structure of 1-methoxy-2,2,2-tris(pyrazol-1-yl)ethane

Ganna Lyubartseva,^a ^* Sean Parkin,^b Morgan D. Coleman ^a and Uma Prasad Mallik ^a

^aDepartment of Biochemistry and Chemistry, Southern Arkansas University, Magnolia, AR 71753, USA, and ^bDepartment of Chemistry, University of Kentucky, Lexington, KY 40506, USA
^*Correspondence e-mail: GannaLyubartseva@saumag.edu

Edited by H. Stoeckli-Evans, University of Neuchâtel, Switzerland (Received 17 August 2014; accepted 18 August 2014; online 23 August 2014)

The title compound, C₁₂H₁₄N₆O, consists of three pyrazole rings bound via nitrogen to the distal ethane carbon of methoxy ethane. The dihedral angles between the three pyrazole rings are 67.62 (14), 73.74 (14), and 78.92 (12)°. In the crystal, molecules are linked by bifurcated C—H,H⋯N hydrogen bonds, forming double-stranded chains along [001]. The chains are linked via C—H⋯O hydrogen bonds, forming a three-dimensional framework structure. The crystal was refined as a perfect (0.5:0.5) inversion twin.

Keywords: crystal structure; tris(pyrazol-1-yl)ethane; scorpionate ligands.

CCDC reference: 1019968

1. Related literature

For properties of pyrazole-based tridentate ligands, see: Paulo et al. (2004 ); Bigmore et al. (2005 ). For nickel and cobalt complexes of N-donor tridentate scorpionate ligands, see: Lyubartseva et al. (2011 , 2012 , 2013a ,b ); Lyubartseva & Parkin (2009 ). For the synthesis of the title compound, see: Maria et al. (2007 ).

2. Experimental

2.1. Crystal data

C₁₂H₁₄N₆O
M_r = 258.29
Monoclinic, C c
a = 12.5828 (3) Å
b = 12.3847 (3) Å
c = 8.4807 (2) Å
β = 102.5635 (11)°
V = 1289.94 (5) Å³
Z = 4
Mo Kα radiation
μ = 0.09 mm⁻¹
T = 90 K
0.28 × 0.20 × 0.16 mm

2.2. Data collection

Nonius KappaCCD diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.749, T_max = 0.942
11397 measured reflections
2934 independent reflections
2386 reflections with I > 2σ(I)
R_int = 0.032

2.3. Refinement

R[F² > 2σ(F²)] = 0.042
wR(F²) = 0.102
S = 1.10
2934 reflections
174 parameters
2 restraints
H-atom parameters constrained
Δρ_max = 0.23 e Å⁻³
Δρ_min = −0.18 e Å⁻³
Absolute structure: Refined as a perfect (i.e. 50:50) inversion twin

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C5—H5A⋯N2ⁱ	0.95	2.51	3.453 (4)	171
C9—H9A⋯N2ⁱⁱ	0.95	2.61	3.433 (4)	145
C4—H4A⋯O1ⁱⁱⁱ	0.95	2.53	3.444 (4)	162
Symmetry codes: (i) $[x, -y+1, z+{\script{1\over 2}}]$ ; (ii) x, y, z+1; (iii) $[x+{\script{1\over 2}}, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]$ .

Data collection: COLLECT (Nonius, 1998 ); cell refinement: SCALEPACK (Otwinowski & Minor, 1997 ); data reduction: DENZO-SMN (Otwinowski & Minor, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2008); molecular graphics: XP in SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL2014 and PLATON (Spek, 2009 ).

Supporting information

CCDC reference: 1019968

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536814018789/su2774sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536814018789/su2774Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536814018789/su2774Isup3.cml

checkCIF report

Synthesis and crystallization top

The title compound was prepared using the published procedure (Maria et al., 2007). Colourless block-like crystals were obtained by slow evaporation of a diethyl ether solution of pure product. Spectral and other characterizations are in good accordance with the previously reported data (Maria et al., 2007).

Refinement top

H atoms were located in difference Fourier maps, but were subsequently included in the refinement using a riding model approximation: C—H = 0.95 - 0.99 Å with U_iso(H) = 1.5U_eq(C-methyl) and = 1.2U_eq(C) for other H atoms. The crystal was refined as a perfect (0.5:0.5) inversion twin.

Related literature top

For properties of pyrazole-based tridentate ligands, see: Paulo et al. (2004); Bigmore et al. (2005). For nickel and cobalt complexes of N-donor tridentate scorpionate ligands, see: Lyubartseva et al. (2011, 2012, 2013a,b); Lyubartseva & Parkin (2009). For the synthesis of the title compound, see: Maria et al. (2007).

Computing details top

Data collection: COLLECT (Nonius, 1998); cell refinement: SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO-SMN (Otwinowski & Minor, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2008); molecular graphics: XP in SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL2014 (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top

Fig. 1. View of molecular structure of the title molecule, with atom labelling. Displacement ellipsoids are drawn at the 50% probability level. H atoms have been omitted for clarity.

1-Methoxy-2,2,2-tris(pyrazol-1-yl)ethane top

Crystal data top

C₁₂H₁₄N₆O	F(000) = 544
M_r = 258.29	D_x = 1.330 Mg m⁻³
Monoclinic, Cc	Mo Kα radiation, λ = 0.71073 Å
a = 12.5828 (3) Å	Cell parameters from 1549 reflections
b = 12.3847 (3) Å	θ = 1.0–27.5°
c = 8.4807 (2) Å	µ = 0.09 mm⁻¹
β = 102.5635 (11)°	T = 90 K
V = 1289.94 (5) Å³	Block, colourless
Z = 4	0.28 × 0.20 × 0.16 mm

Data collection top

Nonius KappaCCD diffractometer	2934 independent reflections
Radiation source: fine-focus sealed-tube	2386 reflections with I > 2σ(I)
Detector resolution: 9.1 pixels mm^-1	R_int = 0.032
ϕ and ω scans at fixed χ = 55°	θ_max = 27.5°, θ_min = 2.3°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −16→16
T_min = 0.749, T_max = 0.942	k = −16→16
11397 measured reflections	l = −10→11

Refinement top

Refinement on F²	Hydrogen site location: difference Fourier map
Least-squares matrix: full	H-atom parameters constrained
R[F² > 2σ(F²)] = 0.042	w = 1/[σ²(F_o²) + (0.0453P)² + 0.5917P] where P = (F_o² + 2F_c²)/3
wR(F²) = 0.102	(Δ/σ)_max < 0.001
S = 1.10	Δρ_max = 0.23 e Å⁻³
2934 reflections	Δρ_min = −0.18 e Å⁻³
174 parameters	Extinction correction: SHELXL2014 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
2 restraints	Extinction coefficient: 0.0127 (19)
Primary atom site location: structure-invariant direct methods	Absolute structure: Refined as a perfect (i.e. 50:50) inversion twin.
Secondary atom site location: difference Fourier map

Crystal data top

C₁₂H₁₄N₆O	V = 1289.94 (5) Å³
M_r = 258.29	Z = 4
Monoclinic, Cc	Mo Kα radiation
a = 12.5828 (3) Å	µ = 0.09 mm⁻¹
b = 12.3847 (3) Å	T = 90 K
c = 8.4807 (2) Å	0.28 × 0.20 × 0.16 mm
β = 102.5635 (11)°

Data collection top

Nonius KappaCCD diffractometer	2934 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	2386 reflections with I > 2σ(I)
T_min = 0.749, T_max = 0.942	R_int = 0.032
11397 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.042	2 restraints
wR(F²) = 0.102	H-atom parameters constrained
S = 1.10	Δρ_max = 0.23 e Å⁻³
2934 reflections	Δρ_min = −0.18 e Å⁻³
174 parameters	Absolute structure: Refined as a perfect (i.e. 50:50) inversion twin.

Special details top

Experimental. The crystal was mounted with polyisobutene oil on the tip of a fine glass fibre, which was fastened in a copper mounting pin with electrical solder. It was placed directly into the cold gas stream of a liquid nitrogen based cryostat, according to published methods (Hope, 1994; Parkin & Hope, 1998).

Diffraction data were collected with the crystal at 90 K, which is standard practice in this laboratory for the majority of flash-cooled crystals.

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 progress was checked using PLATON (Spek, 2009) and by an R-tensor (Parkin, 2000). The final model was further checked with the IUCr utility checkCIF.

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

	x	y	z	U_iso*/U_eq
O1	0.34875 (17)	0.16856 (16)	0.5089 (3)	0.0305 (5)
N1	0.62903 (19)	0.25690 (19)	0.5191 (3)	0.0229 (5)
N2	0.6299 (2)	0.2508 (2)	0.3598 (3)	0.0291 (6)
N3	0.4892 (2)	0.35743 (18)	0.5996 (3)	0.0255 (6)
N4	0.5617 (2)	0.4320 (2)	0.6770 (4)	0.0378 (7)
N5	0.5520 (2)	0.1924 (2)	0.7270 (3)	0.0236 (5)
N6	0.5898 (2)	0.0891 (2)	0.7266 (3)	0.0296 (6)
C1	0.5280 (2)	0.2497 (2)	0.5740 (3)	0.0212 (6)
C2	0.7343 (3)	0.2658 (3)	0.3557 (4)	0.0336 (7)
H2A	0.7610	0.2658	0.2591	0.040*
C3	0.8001 (2)	0.2816 (2)	0.5100 (4)	0.0318 (7)
H3A	0.8765	0.2933	0.5376	0.038*
C4	0.7295 (3)	0.2762 (2)	0.6118 (4)	0.0303 (7)
H4A	0.7475	0.2845	0.7259	0.036*
C5	0.5010 (3)	0.5170 (3)	0.6921 (5)	0.0426 (9)
H5A	0.5290	0.5831	0.7406	0.051*
C6	0.3900 (3)	0.4977 (3)	0.6277 (5)	0.0394 (8)
H6A	0.3311	0.5461	0.6252	0.047*
C7	0.3848 (3)	0.3954 (3)	0.5699 (4)	0.0307 (7)
H7A	0.3210	0.3574	0.5187	0.037*
C8	0.6077 (3)	0.0592 (3)	0.8804 (4)	0.0330 (7)
H8A	0.6344	−0.0098	0.9187	0.040*
C9	0.5825 (3)	0.1410 (3)	0.9791 (4)	0.0379 (8)
H9A	0.5884	0.1385	1.0927	0.045*
C10	0.5474 (2)	0.2258 (3)	0.8775 (4)	0.0324 (7)
H10A	0.5244	0.2946	0.9067	0.039*
C11	0.4437 (2)	0.1869 (2)	0.4498 (4)	0.0252 (6)
H11A	0.4249	0.2284	0.3478	0.030*
H11B	0.4751	0.1169	0.4266	0.030*
C12	0.3184 (3)	0.0580 (3)	0.5101 (5)	0.0384 (8)
H12A	0.2517	0.0515	0.5511	0.058*
H12B	0.3770	0.0171	0.5800	0.058*
H12C	0.3057	0.0291	0.4000	0.058*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0238 (11)	0.0263 (11)	0.0426 (13)	−0.0028 (9)	0.0099 (9)	−0.0036 (9)
N1	0.0226 (13)	0.0254 (12)	0.0214 (13)	0.0009 (10)	0.0062 (10)	0.0004 (10)
N2	0.0335 (15)	0.0325 (14)	0.0239 (13)	0.0045 (11)	0.0115 (11)	0.0029 (11)
N3	0.0233 (12)	0.0213 (12)	0.0324 (13)	−0.0003 (10)	0.0072 (10)	−0.0024 (11)
N4	0.0282 (14)	0.0256 (14)	0.0600 (19)	−0.0051 (12)	0.0103 (13)	−0.0140 (13)
N5	0.0247 (12)	0.0237 (12)	0.0227 (12)	−0.0018 (10)	0.0058 (10)	−0.0001 (10)
N6	0.0359 (15)	0.0213 (13)	0.0294 (14)	0.0003 (10)	0.0025 (11)	0.0033 (10)
C1	0.0197 (14)	0.0219 (14)	0.0233 (15)	0.0004 (10)	0.0074 (12)	−0.0010 (11)
C2	0.0357 (17)	0.0306 (17)	0.0400 (19)	0.0029 (14)	0.0203 (15)	0.0051 (14)
C3	0.0222 (15)	0.0285 (15)	0.048 (2)	0.0000 (12)	0.0143 (15)	0.0000 (14)
C4	0.0257 (16)	0.0316 (17)	0.0334 (17)	0.0020 (13)	0.0057 (13)	−0.0024 (13)
C5	0.0370 (18)	0.0272 (18)	0.064 (2)	−0.0032 (14)	0.0130 (17)	−0.0149 (16)
C6	0.0308 (17)	0.0274 (17)	0.061 (2)	0.0062 (14)	0.0116 (16)	−0.0077 (15)
C7	0.0249 (15)	0.0287 (16)	0.0374 (17)	0.0024 (12)	0.0042 (13)	−0.0008 (13)
C8	0.0248 (16)	0.0364 (18)	0.0353 (18)	−0.0083 (14)	0.0009 (13)	0.0113 (15)
C9	0.0300 (17)	0.060 (2)	0.0246 (16)	−0.0035 (16)	0.0075 (13)	0.0056 (15)
C10	0.0260 (16)	0.0457 (19)	0.0282 (16)	−0.0028 (14)	0.0122 (13)	−0.0058 (14)
C11	0.0214 (15)	0.0256 (14)	0.0280 (15)	0.0008 (11)	0.0041 (12)	−0.0027 (12)
C12	0.038 (2)	0.0282 (17)	0.051 (2)	−0.0059 (14)	0.0126 (17)	0.0031 (16)

Geometric parameters (Å, º) top

O1—C11	1.411 (3)	C3—H3A	0.9500
O1—C12	1.423 (4)	C4—H4A	0.9500
N1—N2	1.356 (3)	C5—C6	1.405 (5)
N1—C4	1.357 (4)	C5—H5A	0.9500
N1—C1	1.448 (3)	C6—C7	1.355 (5)
N2—C2	1.335 (4)	C6—H6A	0.9500
N3—N4	1.363 (4)	C7—H7A	0.9500
N3—C7	1.365 (4)	C8—C9	1.394 (5)
N3—C1	1.454 (3)	C8—H8A	0.9500
N4—C5	1.323 (4)	C9—C10	1.369 (5)
N5—C10	1.354 (4)	C9—H9A	0.9500
N5—N6	1.364 (3)	C10—H10A	0.9500
N5—C1	1.452 (4)	C11—H11A	0.9900
N6—C8	1.327 (4)	C11—H11B	0.9900
C1—C11	1.534 (4)	C12—H12A	0.9800
C2—C3	1.402 (5)	C12—H12B	0.9800
C2—H2A	0.9500	C12—H12C	0.9800
C3—C4	1.369 (4)

C11—O1—C12	114.0 (2)	N4—C5—H5A	124.0
N2—N1—C4	112.3 (2)	C6—C5—H5A	124.0
N2—N1—C1	121.0 (2)	C7—C6—C5	105.3 (3)
C4—N1—C1	126.7 (2)	C7—C6—H6A	127.3
C2—N2—N1	103.8 (3)	C5—C6—H6A	127.3
N4—N3—C7	111.9 (2)	C6—C7—N3	106.7 (3)
N4—N3—C1	118.8 (2)	C6—C7—H7A	126.7
C7—N3—C1	129.0 (2)	N3—C7—H7A	126.7
C5—N4—N3	104.2 (3)	N6—C8—C9	112.0 (3)
C10—N5—N6	112.0 (3)	N6—C8—H8A	124.0
C10—N5—C1	130.5 (3)	C9—C8—H8A	124.0
N6—N5—C1	117.4 (2)	C10—C9—C8	105.3 (3)
C8—N6—N5	104.1 (3)	C10—C9—H9A	127.4
N1—C1—N5	106.9 (2)	C8—C9—H9A	127.4
N1—C1—N3	109.8 (2)	N5—C10—C9	106.6 (3)
N5—C1—N3	109.0 (2)	N5—C10—H10A	126.7
N1—C1—C11	109.6 (2)	C9—C10—H10A	126.7
N5—C1—C11	110.1 (2)	O1—C11—C1	110.5 (2)
N3—C1—C11	111.3 (2)	O1—C11—H11A	109.5
N2—C2—C3	112.3 (3)	C1—C11—H11A	109.5
N2—C2—H2A	123.8	O1—C11—H11B	109.5
C3—C2—H2A	123.8	C1—C11—H11B	109.5
C4—C3—C2	104.4 (3)	H11A—C11—H11B	108.1
C4—C3—H3A	127.8	O1—C12—H12A	109.5
C2—C3—H3A	127.8	O1—C12—H12B	109.5
N1—C4—C3	107.1 (3)	H12A—C12—H12B	109.5
N1—C4—H4A	126.4	O1—C12—H12C	109.5
C3—C4—H4A	126.4	H12A—C12—H12C	109.5
N4—C5—C6	112.0 (3)	H12B—C12—H12C	109.5

C4—N1—N2—C2	0.6 (3)	N4—N3—C1—C11	−165.4 (3)
C1—N1—N2—C2	177.0 (3)	C7—N3—C1—C11	21.3 (4)
C7—N3—N4—C5	−1.0 (4)	N1—N2—C2—C3	−0.1 (3)
C1—N3—N4—C5	−175.4 (3)	N2—C2—C3—C4	−0.4 (4)
C10—N5—N6—C8	0.5 (3)	N2—N1—C4—C3	−0.9 (3)
C1—N5—N6—C8	178.0 (2)	C1—N1—C4—C3	−177.1 (3)
N2—N1—C1—N5	144.6 (2)	C2—C3—C4—N1	0.8 (3)
C4—N1—C1—N5	−39.6 (4)	N3—N4—C5—C6	0.9 (4)
N2—N1—C1—N3	−97.3 (3)	N4—C5—C6—C7	−0.5 (5)
C4—N1—C1—N3	78.6 (3)	C5—C6—C7—N3	−0.2 (4)
N2—N1—C1—C11	25.2 (3)	N4—N3—C7—C6	0.8 (4)
C4—N1—C1—C11	−158.9 (3)	C1—N3—C7—C6	174.4 (3)
C10—N5—C1—N1	115.6 (3)	N5—N6—C8—C9	−0.2 (3)
N6—N5—C1—N1	−61.3 (3)	N6—C8—C9—C10	−0.2 (4)
C10—N5—C1—N3	−3.0 (4)	N6—N5—C10—C9	−0.6 (3)
N6—N5—C1—N3	−179.9 (2)	C1—N5—C10—C9	−177.7 (3)
C10—N5—C1—C11	−125.4 (3)	C8—C9—C10—N5	0.4 (3)
N6—N5—C1—C11	57.7 (3)	C12—O1—C11—C1	−124.7 (3)
N4—N3—C1—N1	−43.9 (3)	N1—C1—C11—O1	173.5 (2)
C7—N3—C1—N1	142.8 (3)	N5—C1—C11—O1	56.2 (3)
N4—N3—C1—N5	72.9 (3)	N3—C1—C11—O1	−64.8 (3)
C7—N3—C1—N5	−100.4 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C5—H5A···N2ⁱ	0.95	2.51	3.453 (4)	171
C9—H9A···N2ⁱⁱ	0.95	2.61	3.433 (4)	145
C4—H4A···O1ⁱⁱⁱ	0.95	2.53	3.444 (4)	162

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C5—H5A···N2ⁱ	0.95	2.51	3.453 (4)	171
C9—H9A···N2ⁱⁱ	0.95	2.61	3.433 (4)	145
C4—H4A···O1ⁱⁱⁱ	0.95	2.53	3.444 (4)	162

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

Acknowledgements

GL is grateful to the Southern Arkansas University Faculty Research Grant for financial support.

References

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Volume 70| Part 9| September 2014| Pages o1047-o1048

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