2,2,2-Tris(pyrazol-1-yl)ethanol

McLauchlan, C.C.; Smith, B.L.; Pippins, R.S.; Nelson, B.M.

doi:10.1107/S1600536811012931

organic compounds

CRYSTALLOGRAPHIC
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ISSN: 2056-9890

Volume 67| Part 5| May 2011| Pages o1133-o1134

doi:10.1107/S1600536811012931

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2,2,2-Tris(pyrazol-1-yl)ethanol

Craig C. McLauchlan,^a ^* Brigette L. Smith,^a Reyhana S. Pippins ^a and Brandon M. Nelson ^a

^aDepartment of Chemistry, Illinois State University, Campus Box 4160, Normal, IL 61790-4160, USA
^*Correspondence e-mail: mclauchlan@ilstu.edu

(Received 31 March 2011; accepted 6 April 2011; online 16 April 2011)

The title compound TPE, C₁₁H₁₂N₆O, was prepared by slow evaporation from diethyl ether. In the crystal, there is a hydrogen bond between the alcohol H atom and an N in the pyrazole ring of a neighboring molecule.

Related literature

For the original preparation, see: Reger et al. (2000 ). The title compound was prepared as part of our efforts to study tridentate scorpionate and psuedo-scorpionate ligands for coordination to vanadium, see: McLauchlan et al. (2004 , 2009 ); McLauchlan & McDonald (2005 , 2006 ). For coordination complexes with TPE, see: Sánchez-Méndez et al. (2004 ), Garcia-Orozco et al. (2006 ); Silva et al. (2009 ). For applications following substitution of the alcohol, see: Reger, Wright et al. (2001 ); Reger, Semeniuc et al. (2001 ); Reger & Grattan (2003 ); Pettinari & Pettinari (2005 ); Silva et al. (2009).

Experimental

Crystal data

C₁₁H₁₂N₆O
M_r = 244.27
Monoclinic, C 2/c
a = 19.6589 (14) Å
b = 11.5155 (8) Å
c = 12.4185 (18) Å
β = 125.740 (1)°
V = 2281.9 (4) Å³
Z = 8
Mo Kα radiation
μ = 0.10 mm⁻¹
T = 93 K
0.40 × 0.39 × 0.33 mm

Data collection

Bruker SMART APEX CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2008 ) T_min = 0.699, T_max = 0.746
9505 measured reflections
2334 independent reflections
2187 reflections with I > 2σ(I)
R_int = 0.018

Refinement

R[F² > 2σ(F²)] = 0.034
wR(F²) = 0.087
S = 1.05
2334 reflections
167 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.27 e Å⁻³
Δρ_min = −0.25 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1O⋯N5ⁱ	0.851 (18)	2.003 (18)	2.8494 (13)	172.9 (16)
Symmetry code: (i) $[x, -y+2, z-{\script{1\over 2}}]$ .

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ); program(s) used to refine structure: SHELXTL; molecular graphics: ORTEPIII (Burnett & Johnson, 1996 ) and Mercury (Macrae et al., 2008 ); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536811012931/dn2673sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811012931/dn2673Isup2.hkl

checkCIF report

Comment top

In our efforts to study tridentate scorpionate and psuedo-scorpionate ligands for coordination to vanadium (McLauchlan et al., 2004; McLauchlan & McDonald, 2005; McLauchlan & McDonald, 2006; McLauchlan et al., 2009), we have prepared and crystallized the title compound, tris-2,2,2-(1-pyrazolyl)ethanol, TPE, Figure 1. TPE had been reported by Reger et al. (2000) and used as a valuable tool for coordination chemistry owing to the ability to functionalize the alcohol (inter alia Reger, Wright et al., 2001; Reger, Semeniuc et al., 2001; Reger & Grattan, 2003; Pettinari & Pettinari, 2005; Silva et al., 2009). Others have reported coordination complexes with TPE, including Sánchez-Méndez et al.(2004), Garcia-Orozco et al. (2006), and Silva et al. (2009). The structure of TPE shows evidence of hydrogen bonding between the alcoholic H and an N in the pyrazole ring of a neighboring molecule (Table 1) to form chains of TPE parallel to the c axis (Figure 2). The structural parameters are similar to those of that seen in the structure of TPE bound to Cu(II) by Silva et al. (2009).

Related literature top

For the original preparation, see: Reger et al. (2000). For background to this study, see: McLauchlan et al. (2004, 2009); McLauchlan & McDonald (2005, 2006). For coordination with complexes with TPE, see: Sánchez-Méndez et al. (2004), Garcia-Orozco et al. (2006); Silva et al. (2009). For applications with substitution of the alcohol, see: Reger, Wright et al. (2001); Reger, Semeniuc et al. (2001); Reger & Grattan (2003); Pettinari & Pettinari (2005); Silva et al. (2009).

Experimental top

The title compound was prepared using the method of Reger et al. (2000). Use of freshly sublimed KO^tBu was critical for reasonable yield (Silva et al., 2009). Crystals suitable for diffraction study were obtained from slow evaporation of a diethyl ether solution of the product. Characterization data are in line with published data (Reger et al., 2000).

Computing details top

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: ORTEPIII (Burnett & Johnson, 1996) and Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. View of the molecular structure of the title compound showing 50% displacement ellipsoids (arbitrary spheres for the H atoms).
	Fig. 2. Several symmetry equivalent molecules of the title compound viewed along the b axis. Hydrogen bonds between the alcoholic O and the neighboring pyrazole N are indicated in light blue and are parallel to the c axis. The neighboring molecule is related by the symmetry code x, -y + 2, z - 1/2. Non-H-bonding hydrogen atoms have been removed for clarity.

2,2,2-Tris(pyrazol-1-yl)ethanol top

Crystal data top

C₁₁H₁₂N₆O	F(000) = 1024
M_r = 244.27	D_x = 1.422 Mg m⁻³
Monoclinic, C2/c	Melting point: 387(2) K
Hall symbol: -C 2yc	Mo Kα radiation, λ = 0.71073 Å
a = 19.6589 (14) Å	Cell parameters from 6831 reflections
b = 11.5155 (8) Å	θ = 2.2–31.4°
c = 12.4185 (18) Å	µ = 0.10 mm⁻¹
β = 125.740 (1)°	T = 93 K
V = 2281.9 (4) Å³	Block, colorless
Z = 8	0.40 × 0.39 × 0.33 mm

Data collection top

Bruker SMART APEX CCD diffractometer	2334 independent reflections
Radiation source: fine-focus sealed tube	2187 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.018
ω scans	θ_max = 26.4°, θ_min = 2.2°
Absorption correction: multi-scan (SADABS; Bruker, 2008)	h = −24→23
T_min = 0.699, T_max = 0.746	k = −14→14
9505 measured reflections	l = −15→15

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) = 0.087	H atoms treated by a mixture of independent and constrained refinement
S = 1.05	w = 1/[σ²(F_o²) + (0.0454P)² + 1.8611P] where P = (F_o² + 2F_c²)/3
2334 reflections	(Δ/σ)_max = 0.001
167 parameters	Δρ_max = 0.27 e Å⁻³
0 restraints	Δρ_min = −0.25 e Å⁻³

Crystal data top

C₁₁H₁₂N₆O	V = 2281.9 (4) Å³
M_r = 244.27	Z = 8
Monoclinic, C2/c	Mo Kα radiation
a = 19.6589 (14) Å	µ = 0.10 mm⁻¹
b = 11.5155 (8) Å	T = 93 K
c = 12.4185 (18) Å	0.40 × 0.39 × 0.33 mm
β = 125.740 (1)°

Data collection top

Bruker SMART APEX CCD diffractometer	2334 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2008)	2187 reflections with I > 2σ(I)
T_min = 0.699, T_max = 0.746	R_int = 0.018
9505 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.034	0 restraints
wR(F²) = 0.087	H atoms treated by a mixture of independent and constrained refinement
S = 1.05	Δρ_max = 0.27 e Å⁻³
2334 reflections	Δρ_min = −0.25 e Å⁻³
167 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. H atoms for the pyrazoles and the methylene unit were modeled in fixed positions whereas the alcoholic H (on O1) was allowed to refine freely.

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

	x	y	z	U_iso*/U_eq
O1	0.16215 (5)	0.93915 (7)	0.05201 (8)	0.01904 (19)
N1	0.14888 (6)	1.06979 (8)	0.22818 (9)	0.0163 (2)
N2	0.18638 (6)	0.87863 (8)	0.30788 (9)	0.0161 (2)
N3	0.29052 (6)	1.02830 (8)	0.40204 (9)	0.0169 (2)
N4	0.16341 (6)	1.17862 (8)	0.20317 (10)	0.0198 (2)
N5	0.17186 (6)	0.88180 (8)	0.40312 (9)	0.0207 (2)
N6	0.36644 (6)	0.98761 (9)	0.43963 (10)	0.0225 (2)
C1	0.08823 (7)	1.22859 (10)	0.13521 (11)	0.0196 (2)
H1A	0.0782	1.3066	0.1046	0.024*
C2	0.02568 (7)	1.15312 (10)	0.11394 (11)	0.0214 (2)
H2A	−0.0324	1.1691	0.0684	0.026*
C3	0.06644 (7)	1.05131 (10)	0.17310 (11)	0.0198 (2)
H3A	0.0418	0.9812	0.1753	0.024*
C4	0.13735 (8)	0.77969 (10)	0.39302 (12)	0.0231 (3)
H4A	0.1210	0.7557	0.4480	0.028*
C5	0.12786 (7)	0.71147 (10)	0.29158 (12)	0.0221 (2)
H5A	0.1045	0.6358	0.2652	0.027*
C6	0.15956 (7)	0.77737 (9)	0.23876 (11)	0.0180 (2)
H6A	0.1623	0.7563	0.1674	0.022*
C7	0.42096 (8)	1.04416 (11)	0.55168 (12)	0.0242 (3)
H7A	0.4800	1.0341	0.6022	0.029*
C8	0.38124 (8)	1.12033 (10)	0.58653 (11)	0.0231 (3)
H8A	0.4068	1.1699	0.6617	0.028*
C9	0.29742 (7)	1.10762 (10)	0.48837 (11)	0.0199 (2)
H9A	0.2527	1.1469	0.4821	0.024*
C10	0.21515 (7)	0.98322 (9)	0.28018 (10)	0.0156 (2)
C11	0.23604 (7)	0.95939 (10)	0.17984 (10)	0.0168 (2)
H11A	0.2662	1.0269	0.1771	0.020*
H11B	0.2732	0.8908	0.2089	0.020*
H1O	0.1605 (10)	0.9921 (15)	0.0027 (17)	0.033 (4)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0198 (4)	0.0210 (4)	0.0151 (4)	−0.0026 (3)	0.0094 (3)	0.0001 (3)
N1	0.0177 (5)	0.0141 (4)	0.0187 (5)	−0.0005 (3)	0.0116 (4)	−0.0007 (3)
N2	0.0192 (5)	0.0152 (4)	0.0161 (4)	0.0000 (3)	0.0115 (4)	−0.0003 (3)
N3	0.0167 (5)	0.0166 (4)	0.0171 (5)	−0.0006 (3)	0.0096 (4)	−0.0015 (4)
N4	0.0228 (5)	0.0154 (5)	0.0249 (5)	0.0002 (4)	0.0160 (4)	0.0017 (4)
N5	0.0278 (5)	0.0207 (5)	0.0192 (5)	−0.0005 (4)	0.0169 (4)	0.0002 (4)
N6	0.0168 (5)	0.0238 (5)	0.0220 (5)	0.0014 (4)	0.0087 (4)	−0.0031 (4)
C1	0.0235 (6)	0.0177 (5)	0.0190 (5)	0.0032 (4)	0.0132 (5)	0.0008 (4)
C2	0.0176 (5)	0.0227 (6)	0.0208 (6)	0.0010 (4)	0.0095 (5)	−0.0018 (4)
C3	0.0175 (5)	0.0199 (5)	0.0215 (5)	−0.0029 (4)	0.0111 (5)	−0.0029 (4)
C4	0.0292 (6)	0.0211 (6)	0.0255 (6)	−0.0015 (5)	0.0196 (5)	0.0024 (4)
C5	0.0246 (6)	0.0168 (5)	0.0266 (6)	−0.0023 (4)	0.0159 (5)	−0.0010 (4)
C6	0.0189 (5)	0.0157 (5)	0.0187 (5)	0.0000 (4)	0.0106 (5)	−0.0019 (4)
C7	0.0197 (6)	0.0265 (6)	0.0203 (6)	−0.0025 (5)	0.0081 (5)	−0.0023 (5)
C8	0.0267 (6)	0.0234 (6)	0.0184 (6)	−0.0069 (5)	0.0128 (5)	−0.0045 (4)
C9	0.0254 (6)	0.0189 (5)	0.0205 (5)	−0.0032 (4)	0.0163 (5)	−0.0031 (4)
C10	0.0158 (5)	0.0147 (5)	0.0162 (5)	−0.0004 (4)	0.0093 (4)	−0.0010 (4)
C11	0.0166 (5)	0.0188 (5)	0.0161 (5)	−0.0012 (4)	0.0102 (4)	−0.0009 (4)

Geometric parameters (Å, º) top

O1—C11	1.4108 (13)	C2—C3	1.3669 (17)
O1—H1O	0.851 (18)	C2—H2A	0.9500
N1—C3	1.3582 (14)	C3—H3A	0.9500
N1—N4	1.3610 (13)	C4—C5	1.4015 (17)
N1—C10	1.4578 (13)	C4—H4A	0.9500
N2—C6	1.3586 (14)	C5—C6	1.3683 (16)
N2—N5	1.3698 (13)	C5—H5A	0.9500
N2—C10	1.4546 (14)	C6—H6A	0.9500
N3—C9	1.3535 (14)	C7—C8	1.4005 (18)
N3—N6	1.3607 (13)	C7—H7A	0.9500
N3—C10	1.4613 (14)	C8—C9	1.3696 (17)
N4—C1	1.3307 (15)	C8—H8A	0.9500
N5—C4	1.3263 (15)	C9—H9A	0.9500
N6—C7	1.3292 (16)	C10—C11	1.5475 (15)
C1—C2	1.3992 (16)	C11—H11A	0.9900
C1—H1A	0.9500	C11—H11B	0.9900

C11—O1—H1O	105.9 (11)	C6—C5—H5A	127.4
C3—N1—N4	112.15 (9)	C4—C5—H5A	127.4
C3—N1—C10	127.64 (9)	N2—C6—C5	106.90 (10)
N4—N1—C10	118.58 (9)	N2—C6—H6A	126.6
C6—N2—N5	111.62 (9)	C5—C6—H6A	126.6
C6—N2—C10	128.49 (9)	N6—C7—C8	112.10 (11)
N5—N2—C10	119.22 (9)	N6—C7—H7A	124.0
C9—N3—N6	112.23 (9)	C8—C7—H7A	124.0
C9—N3—C10	129.19 (9)	C9—C8—C7	104.84 (10)
N6—N3—C10	118.58 (9)	C9—C8—H8A	127.6
C1—N4—N1	103.86 (9)	C7—C8—H8A	127.6
C4—N5—N2	104.35 (9)	N3—C9—C8	106.80 (10)
C7—N6—N3	104.04 (9)	N3—C9—H9A	126.6
N4—C1—C2	112.28 (10)	C8—C9—H9A	126.6
N4—C1—H1A	123.9	N2—C10—N1	107.50 (8)
C2—C1—H1A	123.9	N2—C10—N3	110.38 (9)
C3—C2—C1	104.87 (10)	N1—C10—N3	108.60 (8)
C3—C2—H2A	127.6	N2—C10—C11	111.49 (8)
C1—C2—H2A	127.6	N1—C10—C11	110.70 (9)
N1—C3—C2	106.78 (10)	N3—C10—C11	108.15 (9)
N1—C3—H3A	126.6	O1—C11—C10	110.62 (9)
C2—C3—H3A	126.6	O1—C11—H11A	109.5
N5—C4—C5	111.97 (10)	C10—C11—H11A	109.5
N5—C4—H4A	124.0	O1—C11—H11B	109.5
C5—C4—H4A	124.0	C10—C11—H11B	109.5
C6—C5—C4	105.14 (10)	H11A—C11—H11B	108.1

C3—N1—N4—C1	2.18 (12)	C6—N2—C10—N1	105.80 (12)
C10—N1—N4—C1	168.76 (9)	N5—N2—C10—N1	−63.96 (12)
C6—N2—N5—C4	1.32 (12)	C6—N2—C10—N3	−135.91 (11)
C10—N2—N5—C4	172.70 (9)	N5—N2—C10—N3	54.33 (12)
C9—N3—N6—C7	−0.22 (13)	C6—N2—C10—C11	−15.69 (15)
C10—N3—N6—C7	−179.92 (10)	N5—N2—C10—C11	174.56 (9)
N1—N4—C1—C2	−1.23 (12)	C3—N1—C10—N2	−20.24 (14)
N4—C1—C2—C3	−0.10 (13)	N4—N1—C10—N2	175.52 (9)
N4—N1—C3—C2	−2.31 (13)	C3—N1—C10—N3	−139.67 (11)
C10—N1—C3—C2	−167.39 (10)	N4—N1—C10—N3	56.09 (12)
C1—C2—C3—N1	1.41 (12)	C3—N1—C10—C11	101.74 (12)
N2—N5—C4—C5	−1.10 (13)	N4—N1—C10—C11	−62.50 (12)
N5—C4—C5—C6	0.51 (14)	C9—N3—C10—N2	−91.92 (13)
N5—N2—C6—C5	−1.04 (12)	N6—N3—C10—N2	87.72 (11)
C10—N2—C6—C5	−171.42 (10)	C9—N3—C10—N1	25.69 (15)
C4—C5—C6—N2	0.32 (13)	N6—N3—C10—N1	−154.67 (9)
N3—N6—C7—C8	0.03 (14)	C9—N3—C10—C11	145.87 (11)
N6—C7—C8—C9	0.15 (14)	N6—N3—C10—C11	−34.49 (13)
N6—N3—C9—C8	0.32 (13)	N2—C10—C11—O1	70.77 (11)
C10—N3—C9—C8	179.98 (10)	N1—C10—C11—O1	−48.84 (12)
C7—C8—C9—N3	−0.28 (13)	N3—C10—C11—O1	−167.70 (8)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1O···N5ⁱ	0.851 (18)	2.003 (18)	2.8494 (13)	172.9 (16)

Symmetry code: (i) x, −y+2, z−1/2.

Experimental details

Crystal data
Chemical formula	C₁₁H₁₂N₆O
M_r	244.27
Crystal system, space group	Monoclinic, C2/c
Temperature (K)	93
a, b, c (Å)	19.6589 (14), 11.5155 (8), 12.4185 (18)
β (°)	125.740 (1)
V (Å³)	2281.9 (4)
Z	8
Radiation type	Mo Kα
µ (mm⁻¹)	0.10
Crystal size (mm)	0.40 × 0.39 × 0.33

Data collection
Diffractometer	Bruker SMART APEX CCD diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2008)
T_min, T_max	0.699, 0.746
No. of measured, independent and observed [I > 2σ(I)] reflections	9505, 2334, 2187
R_int	0.018
(sin θ/λ)_max (Å⁻¹)	0.625

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.034, 0.087, 1.05
No. of reflections	2334
No. of parameters	167
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.27, −0.25

Computer programs: APEX2 (Bruker, 2008), SAINT (Bruker, 2008), SHELXTL (Sheldrick, 2008), ORTEPIII (Burnett & Johnson, 1996) and Mercury (Macrae et al., 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1O···N5ⁱ	0.851 (18)	2.003 (18)	2.8494 (13)	172.9 (16)

Symmetry code: (i) x, −y+2, z−1/2.

Acknowledgements

This work was supported by Illinois State University, the American Chemical Society Petroleum Research Fund (46064-B3) and the National Science Foundation (US, CHE-0645081). RSP also acknowledges the support of the American Chemical Society Project SEED. The authors also thank the STaRBURSTT Cyberdiffraction Consortium and Dr M. Zeller (Youngstown State University) for the data collection.

References

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