organic compounds
1,3-Bis(2,6-diisopropylphenyl)imidazolidinium tetraphenylborate dichloromethane disolvate
aDepartment of Chemistry, Saint Mary's University, 923 Robie Street, Halifax, NS, Canada B3H 3C3
*Correspondence e-mail: jason.masuda@smu.ca
The title compound, C27H39N2+·C24H20B−·2CH2Cl2, is the first reported imidazolidinium cation with the sterically demanding 2,6-diisopropylphenyl groups in the 1,3-positions. The is stabilized by weak intermolecular C—H⋯π(arene) interactions. Due to the bulky nature of both the flanking 2,6-diisopropylphenyl substituents and the tetraphenylborate counter-ion, anion interactions with the imidazolidinium H atom in the 2-position are not observed, also a first for this class of ortho-alkyl-substituted Arduengo-type carbene precursors.
Related literature
There are few examples in the literature of crystallographically characterized imidazolium or imidazolidinium complexes with ortho-alkyl substituted phenyl groups in the 1,3-positions, see: Arduengo et al. (1995, 1999); Fliedel et al. (2007); Hagos et al. (2008).
Experimental
Crystal data
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Data collection: APEX2 (Bruker, 2010); cell SAINT (Bruker, 2010); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).
Supporting information
https://doi.org/10.1107/S1600536810028424/lh5077sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810028424/lh5077Isup2.hkl
1,3-bis(2,6-diisopropylphenyl)imidazolidinium tetraphenylborate dichloromethane disolvate was prepared by reacting 1.00 g (2.34 mol) of the corresponding imidazolidinum chloride (Arduengo et al., 1999) with one equivalent of sodium tetraphenylborate (0.80 g, 2.34 mmol) in dichloromethane. After stirring overnight, the solution was filtered through diatomaceous earth and allowed to slowly evaporate yielding colorless block-like crystals of the title compound. The proton NMR matched that in the literature of the imidazolidinum chloride and is typical of a tetraphenylborate anion.
The H atoms were placed in geometrically idealized positions with C—H distances of 0.93Å (aromatic), 0.98Å (idealized tertiary), 0.97Å (idealized secondary) and 0.96Å (idealized methyl). H atoms were constrained to ride on the parent C atom with Uiso(H) = 1.2Ueq(C) for aromatic and secondary protons and Uiso(H) = 1.5Ueq(C) for the idealized methyl and tertiary protons.
In order to obtain satisfactory thermal parameters for the model, SIMU and DELU restraints were applied to carbon atoms C4>C51.
Imidazolium and imidazolidinium cations are the essential precursors to neutral free carbene compounds in which a divalent carbon with a six-electron valence shell is electronically stabilized by donating amino-substituents and sterically protected by substituted phenyl groups. The title compound is related to the previously prepared 1,3-bis(2,6-diisopropylphenyl)imidazolidinium chloride. As a result of the increased steric bulk associated with the tetraphenylborate anion the title compound is the first reported structure in which the imidazolidinium C-2 hydrogen atom is not within the sum of the Van der Waals radii of any atom in the anion or co-crystalized solvent. The title compound can be compared to previously published structures (Arduengo et al., 1995, 1999; Fliedel et al., 2007; Hagos et al., 2008).
The π(arene) interactions.
of the title compound is shown in Fig. 1. The is stabilized by weak intermolecular C-H···There are few examples in the literature of crystallographically characterized imidazolium or imidazolidinium complexes with ortho-alkyl substituted phenyl groups in the 1,3-positions, see: Arduengo et al. (1995, 1999); Fliedel et al. (2007); Hagos et al. (2008).
Data collection: APEX2 (Bruker, 2010); cell
SAINT (Bruker, 2010); data reduction: SAINT (Bruker, 2010); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).Fig. 1. The asymmetric unit of the title compound, with atom labels and 30% probability displacement ellipsoids for non-H atoms. |
C27H39N2+·C24H20B−·2CH2Cl2 | F(000) = 1872 |
Mr = 880.66 | Dx = 1.155 Mg m−3 |
Monoclinic, Cc | Melting point = 472–475 K |
Hall symbol: C -2yc | Mo Kα radiation, λ = 0.71073 Å |
a = 21.4648 (14) Å | Cell parameters from 7600 reflections |
b = 10.3964 (7) Å | θ = 2.2–25.8° |
c = 22.7524 (15) Å | µ = 0.27 mm−1 |
β = 93.760 (1)° | T = 296 K |
V = 5066.4 (6) Å3 | Block, yellow |
Z = 4 | 0.49 × 0.34 × 0.29 mm |
Bruker APEXII CCD diffractometer | 8396 independent reflections |
Radiation source: fine-focus sealed tube | 7118 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.013 |
φ and ω scans | θmax = 26.0°, θmin = 2.2° |
Absorption correction: multi-scan (SADABS; Bruker, 2010) | h = −26→26 |
Tmin = 0.675, Tmax = 0.746 | k = −12→12 |
17851 measured reflections | l = −22→28 |
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)] = 0.062 | H-atom parameters constrained |
wR(F2) = 0.186 | w = 1/[σ2(Fo2) + (0.0829P)2 + 1.5238P] where P = (Fo2 + 2Fc2)/3 |
S = 1.35 | (Δ/σ)max = 0.001 |
8396 reflections | Δρmax = 0.41 e Å−3 |
549 parameters | Δρmin = −0.44 e Å−3 |
892 restraints | Absolute structure: Flack (1983), 3456 Friedels |
Primary atom site location: structure-invariant direct methods | Absolute structure parameter: −0.11 (10) |
C27H39N2+·C24H20B−·2CH2Cl2 | V = 5066.4 (6) Å3 |
Mr = 880.66 | Z = 4 |
Monoclinic, Cc | Mo Kα radiation |
a = 21.4648 (14) Å | µ = 0.27 mm−1 |
b = 10.3964 (7) Å | T = 296 K |
c = 22.7524 (15) Å | 0.49 × 0.34 × 0.29 mm |
β = 93.760 (1)° |
Bruker APEXII CCD diffractometer | 8396 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2010) | 7118 reflections with I > 2σ(I) |
Tmin = 0.675, Tmax = 0.746 | Rint = 0.013 |
17851 measured reflections |
R[F2 > 2σ(F2)] = 0.062 | H-atom parameters constrained |
wR(F2) = 0.186 | Δρmax = 0.41 e Å−3 |
S = 1.35 | Δρmin = −0.44 e Å−3 |
8396 reflections | Absolute structure: Flack (1983), 3456 Friedels |
549 parameters | Absolute structure parameter: −0.11 (10) |
892 restraints |
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. |
x | y | z | Uiso*/Ueq | ||
C1 | 0.32237 (14) | 0.8042 (3) | 0.34114 (15) | 0.0434 (7) | |
H1 | 0.2942 | 0.8353 | 0.3118 | 0.052* | |
C2 | 0.39497 (16) | 0.8011 (3) | 0.41785 (18) | 0.0519 (9) | |
H2A | 0.3814 | 0.8215 | 0.4566 | 0.062* | |
H2B | 0.4396 | 0.8151 | 0.4177 | 0.062* | |
C3 | 0.37791 (15) | 0.6632 (3) | 0.40044 (16) | 0.0461 (8) | |
H3A | 0.4129 | 0.6188 | 0.3846 | 0.055* | |
H3B | 0.3640 | 0.6149 | 0.4336 | 0.055* | |
C4 | 0.36517 (16) | 1.0162 (3) | 0.3702 (2) | 0.0583 (6) | |
C5 | 0.4123 (2) | 1.0698 (4) | 0.3383 (2) | 0.0696 (7) | |
C6 | 0.4195 (2) | 1.2020 (4) | 0.3413 (3) | 0.0763 (7) | |
H6 | 0.4503 | 1.2417 | 0.3207 | 0.092* | |
C7 | 0.3818 (2) | 1.2746 (5) | 0.3742 (3) | 0.0799 (8) | |
H7 | 0.3876 | 1.3632 | 0.3757 | 0.096* | |
C8 | 0.3361 (2) | 1.2214 (4) | 0.4047 (3) | 0.0740 (7) | |
H8 | 0.3109 | 1.2739 | 0.4262 | 0.089* | |
C9 | 0.32666 (18) | 1.0890 (4) | 0.4041 (2) | 0.0657 (7) | |
C10 | 0.4535 (2) | 0.9890 (5) | 0.3013 (3) | 0.0765 (7) | |
H10 | 0.4493 | 0.8989 | 0.3130 | 0.092* | |
C11 | 0.4323 (3) | 1.0003 (8) | 0.2363 (3) | 0.1121 (14) | |
H11A | 0.4347 | 1.0885 | 0.2242 | 0.168* | |
H11B | 0.3899 | 0.9708 | 0.2303 | 0.168* | |
H11C | 0.4588 | 0.9486 | 0.2134 | 0.168* | |
C12 | 0.5217 (2) | 1.0247 (6) | 0.3085 (3) | 0.0886 (12) | |
H12A | 0.5279 | 1.1069 | 0.2906 | 0.133* | |
H12B | 0.5460 | 0.9609 | 0.2899 | 0.133* | |
H12C | 0.5345 | 1.0291 | 0.3497 | 0.133* | |
C13 | 0.27496 (19) | 1.0312 (4) | 0.4373 (2) | 0.0700 (7) | |
H13 | 0.2771 | 0.9376 | 0.4325 | 0.084* | |
C14 | 0.2814 (3) | 1.0592 (6) | 0.5022 (3) | 0.0930 (11) | |
H14A | 0.3187 | 1.0193 | 0.5192 | 0.139* | |
H14B | 0.2459 | 1.0257 | 0.5206 | 0.139* | |
H14C | 0.2839 | 1.1505 | 0.5083 | 0.139* | |
C15 | 0.2115 (2) | 1.0757 (5) | 0.4093 (3) | 0.0831 (11) | |
H15A | 0.2056 | 1.1651 | 0.4178 | 0.125* | |
H15B | 0.1788 | 1.0262 | 0.4251 | 0.125* | |
H15C | 0.2106 | 1.0635 | 0.3674 | 0.125* | |
C16 | 0.29202 (19) | 0.5791 (4) | 0.3253 (2) | 0.0599 (6) | |
C17 | 0.3132 (2) | 0.5293 (4) | 0.2739 (2) | 0.0692 (7) | |
C18 | 0.2803 (2) | 0.4256 (4) | 0.2483 (2) | 0.0752 (8) | |
H18 | 0.2931 | 0.3896 | 0.2136 | 0.090* | |
C19 | 0.2297 (2) | 0.3767 (4) | 0.2736 (2) | 0.0766 (8) | |
H19 | 0.2086 | 0.3074 | 0.2558 | 0.092* | |
C20 | 0.2087 (2) | 0.4267 (4) | 0.3249 (2) | 0.0715 (7) | |
H20 | 0.1740 | 0.3912 | 0.3411 | 0.086* | |
C21 | 0.23988 (19) | 0.5310 (4) | 0.3526 (2) | 0.0623 (6) | |
C22 | 0.2165 (2) | 0.5901 (4) | 0.4072 (2) | 0.0673 (7) | |
H22 | 0.2524 | 0.6303 | 0.4287 | 0.081* | |
C23 | 0.1891 (2) | 0.4947 (5) | 0.4486 (3) | 0.0830 (10) | |
H23A | 0.1542 | 0.4517 | 0.4286 | 0.125* | |
H23B | 0.1753 | 0.5393 | 0.4823 | 0.125* | |
H23C | 0.2203 | 0.4325 | 0.4610 | 0.125* | |
C24 | 0.1694 (2) | 0.6984 (5) | 0.3905 (3) | 0.0860 (11) | |
H24A | 0.1898 | 0.7650 | 0.3698 | 0.129* | |
H24B | 0.1536 | 0.7334 | 0.4256 | 0.129* | |
H24C | 0.1354 | 0.6642 | 0.3657 | 0.129* | |
C25 | 0.3687 (3) | 0.5847 (5) | 0.2449 (2) | 0.0779 (8) | |
H25 | 0.3918 | 0.6392 | 0.2740 | 0.094* | |
C26 | 0.4138 (3) | 0.4820 (6) | 0.2250 (3) | 0.0993 (13) | |
H26A | 0.4349 | 0.4427 | 0.2588 | 0.149* | |
H26B | 0.4438 | 0.5211 | 0.2011 | 0.149* | |
H26C | 0.3908 | 0.4176 | 0.2024 | 0.149* | |
C27 | 0.3473 (4) | 0.6694 (6) | 0.1931 (3) | 0.1047 (13) | |
H27A | 0.3293 | 0.6168 | 0.1618 | 0.157* | |
H27B | 0.3825 | 0.7154 | 0.1797 | 0.157* | |
H27C | 0.3167 | 0.7295 | 0.2052 | 0.157* | |
C28 | 0.56734 (17) | 0.4344 (3) | 0.57017 (18) | 0.0519 (7) | |
C29 | 0.5472 (3) | 0.3788 (4) | 0.6212 (2) | 0.0755 (10) | |
H29 | 0.5109 | 0.4098 | 0.6364 | 0.091* | |
C30 | 0.5791 (3) | 0.2785 (5) | 0.6505 (3) | 0.0988 (14) | |
H30 | 0.5649 | 0.2456 | 0.6852 | 0.119* | |
C31 | 0.6317 (3) | 0.2287 (5) | 0.6279 (3) | 0.1040 (15) | |
H31 | 0.6526 | 0.1605 | 0.6467 | 0.125* | |
C32 | 0.6528 (3) | 0.2785 (5) | 0.5786 (3) | 0.0925 (13) | |
H32 | 0.6886 | 0.2449 | 0.5634 | 0.111* | |
C33 | 0.62107 (19) | 0.3813 (4) | 0.5497 (2) | 0.0685 (9) | |
H33 | 0.6367 | 0.4149 | 0.5158 | 0.082* | |
C34 | 0.54183 (14) | 0.5733 (3) | 0.46984 (17) | 0.0475 (6) | |
C35 | 0.53663 (18) | 0.4641 (4) | 0.4336 (2) | 0.0611 (8) | |
H35 | 0.5308 | 0.3845 | 0.4511 | 0.073* | |
C36 | 0.5398 (2) | 0.4689 (5) | 0.3730 (2) | 0.0739 (9) | |
H36 | 0.5363 | 0.3936 | 0.3510 | 0.089* | |
C37 | 0.5479 (2) | 0.5841 (6) | 0.3457 (2) | 0.0784 (10) | |
H37 | 0.5505 | 0.5879 | 0.3051 | 0.094* | |
C38 | 0.55225 (18) | 0.6931 (5) | 0.3788 (2) | 0.0702 (9) | |
H38 | 0.5575 | 0.7720 | 0.3605 | 0.084* | |
C39 | 0.54900 (15) | 0.6885 (4) | 0.43912 (19) | 0.0570 (7) | |
H39 | 0.5517 | 0.7650 | 0.4603 | 0.068* | |
C40 | 0.45929 (16) | 0.5707 (3) | 0.54864 (17) | 0.0503 (7) | |
C41 | 0.42234 (18) | 0.4617 (4) | 0.5400 (2) | 0.0597 (8) | |
H41 | 0.4411 | 0.3839 | 0.5313 | 0.072* | |
C42 | 0.35757 (19) | 0.4663 (5) | 0.5439 (2) | 0.0717 (10) | |
H42 | 0.3345 | 0.3909 | 0.5388 | 0.086* | |
C43 | 0.3276 (2) | 0.5772 (5) | 0.5550 (2) | 0.0760 (10) | |
H43 | 0.2844 | 0.5794 | 0.5566 | 0.091* | |
C44 | 0.3623 (2) | 0.6847 (5) | 0.5637 (2) | 0.0743 (10) | |
H44 | 0.3428 | 0.7615 | 0.5725 | 0.089* | |
C45 | 0.42724 (18) | 0.6826 (4) | 0.5598 (2) | 0.0631 (9) | |
H45 | 0.4495 | 0.7590 | 0.5648 | 0.076* | |
C46 | 0.57412 (16) | 0.6805 (3) | 0.57753 (18) | 0.0528 (7) | |
C47 | 0.5579 (2) | 0.7240 (5) | 0.6326 (2) | 0.0745 (10) | |
H47 | 0.5218 | 0.6929 | 0.6481 | 0.089* | |
C48 | 0.5949 (3) | 0.8135 (6) | 0.6650 (3) | 0.0917 (13) | |
H48 | 0.5823 | 0.8418 | 0.7011 | 0.110* | |
C49 | 0.6482 (3) | 0.8594 (5) | 0.6452 (3) | 0.0913 (13) | |
H49 | 0.6722 | 0.9183 | 0.6674 | 0.110* | |
C50 | 0.6665 (2) | 0.8187 (4) | 0.5921 (3) | 0.0786 (11) | |
H50 | 0.7034 | 0.8493 | 0.5780 | 0.094* | |
C51 | 0.62988 (18) | 0.7313 (4) | 0.5591 (2) | 0.0615 (8) | |
H51 | 0.6431 | 0.7052 | 0.5229 | 0.074* | |
C52 | 0.1967 (3) | 0.9707 (6) | 0.1819 (3) | 0.109 (2) | |
H52B | 0.1940 | 0.8877 | 0.1624 | 0.130* | |
H52A | 0.1664 | 1.0279 | 0.1622 | 0.130* | |
C53 | 0.5164 (3) | 0.0513 (8) | 0.5452 (3) | 0.115 (2) | |
H53B | 0.5442 | 0.1185 | 0.5607 | 0.138* | |
H53A | 0.5363 | −0.0309 | 0.5541 | 0.138* | |
B1 | 0.53552 (17) | 0.5659 (4) | 0.54107 (19) | 0.0459 (8) | |
Cl1 | 0.18097 (19) | 0.9538 (4) | 0.25374 (12) | 0.2196 (19) | |
Cl2 | 0.26822 (14) | 1.0308 (4) | 0.1782 (2) | 0.230 (2) | |
Cl3 | 0.44650 (12) | 0.0595 (2) | 0.57959 (13) | 0.1433 (8) | |
Cl4 | 0.50522 (12) | 0.0685 (2) | 0.47076 (10) | 0.1297 (7) | |
N1 | 0.32668 (13) | 0.6829 (2) | 0.35495 (13) | 0.0462 (6) | |
N2 | 0.36081 (11) | 0.8780 (2) | 0.37186 (13) | 0.0442 (6) |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0402 (14) | 0.0456 (16) | 0.0443 (19) | 0.0018 (12) | 0.0016 (13) | 0.0055 (14) |
C2 | 0.0501 (17) | 0.0423 (16) | 0.061 (2) | 0.0011 (13) | −0.0120 (16) | −0.0010 (15) |
C3 | 0.0454 (16) | 0.0414 (16) | 0.051 (2) | 0.0015 (12) | −0.0001 (14) | 0.0040 (14) |
C4 | 0.0478 (12) | 0.0457 (11) | 0.0807 (18) | −0.0015 (10) | −0.0008 (10) | 0.0059 (12) |
C5 | 0.0597 (13) | 0.0571 (11) | 0.0923 (18) | −0.0076 (11) | 0.0079 (12) | 0.0098 (13) |
C6 | 0.0705 (15) | 0.0577 (11) | 0.101 (2) | −0.0091 (12) | 0.0120 (13) | 0.0141 (14) |
C7 | 0.0773 (16) | 0.0564 (13) | 0.106 (2) | −0.0047 (11) | 0.0063 (14) | 0.0069 (13) |
C8 | 0.0679 (15) | 0.0517 (11) | 0.103 (2) | 0.0055 (11) | 0.0079 (13) | 0.0004 (14) |
C9 | 0.0553 (12) | 0.0508 (11) | 0.0909 (18) | 0.0048 (10) | 0.0028 (11) | 0.0037 (13) |
C10 | 0.0697 (14) | 0.0664 (15) | 0.0950 (18) | −0.0061 (13) | 0.0179 (12) | 0.0091 (15) |
C11 | 0.107 (3) | 0.132 (3) | 0.0970 (18) | 0.001 (3) | 0.004 (2) | −0.012 (3) |
C12 | 0.0680 (14) | 0.095 (3) | 0.105 (3) | −0.0053 (18) | 0.0219 (16) | 0.015 (2) |
C13 | 0.0604 (13) | 0.0580 (15) | 0.0924 (17) | 0.0066 (12) | 0.0116 (11) | 0.0007 (15) |
C14 | 0.077 (2) | 0.112 (3) | 0.0894 (16) | 0.001 (2) | 0.0054 (15) | 0.004 (2) |
C15 | 0.0565 (13) | 0.096 (3) | 0.097 (3) | 0.0003 (18) | 0.0058 (17) | 0.001 (2) |
C16 | 0.0669 (14) | 0.0528 (14) | 0.0585 (14) | −0.0079 (11) | −0.0077 (10) | −0.0048 (11) |
C17 | 0.0814 (15) | 0.0645 (15) | 0.0605 (15) | −0.0071 (11) | −0.0034 (11) | −0.0080 (11) |
C18 | 0.0887 (17) | 0.0692 (16) | 0.0664 (17) | −0.0067 (12) | −0.0041 (13) | −0.0160 (13) |
C19 | 0.0867 (16) | 0.0668 (16) | 0.0742 (16) | −0.0129 (13) | −0.0099 (13) | −0.0131 (12) |
C20 | 0.0742 (16) | 0.0645 (15) | 0.0743 (17) | −0.0164 (12) | −0.0060 (13) | −0.0075 (12) |
C21 | 0.0648 (14) | 0.0550 (14) | 0.0656 (14) | −0.0070 (10) | −0.0069 (10) | −0.0036 (11) |
C22 | 0.0648 (15) | 0.0627 (15) | 0.0740 (16) | −0.0080 (11) | 0.0003 (12) | −0.0079 (11) |
C23 | 0.083 (2) | 0.081 (2) | 0.086 (2) | −0.0095 (19) | 0.0163 (19) | −0.0005 (18) |
C24 | 0.081 (2) | 0.076 (2) | 0.101 (3) | 0.0090 (16) | 0.007 (2) | −0.0066 (18) |
C25 | 0.0927 (17) | 0.0788 (17) | 0.0623 (16) | −0.0117 (12) | 0.0057 (12) | −0.0089 (14) |
C26 | 0.107 (3) | 0.103 (3) | 0.091 (3) | 0.005 (2) | 0.026 (2) | 0.001 (2) |
C27 | 0.138 (3) | 0.094 (3) | 0.083 (3) | 0.001 (2) | 0.019 (2) | 0.015 (2) |
C28 | 0.0546 (15) | 0.0444 (16) | 0.0549 (19) | −0.0039 (12) | −0.0088 (14) | −0.0031 (12) |
C29 | 0.097 (3) | 0.067 (2) | 0.061 (2) | −0.0109 (18) | −0.0046 (17) | 0.0102 (18) |
C30 | 0.139 (4) | 0.073 (3) | 0.080 (3) | −0.017 (2) | −0.029 (2) | 0.024 (2) |
C31 | 0.133 (4) | 0.059 (2) | 0.111 (3) | 0.007 (2) | −0.059 (3) | 0.005 (2) |
C32 | 0.092 (3) | 0.070 (2) | 0.110 (3) | 0.026 (2) | −0.037 (2) | −0.016 (2) |
C33 | 0.0610 (19) | 0.060 (2) | 0.082 (3) | 0.0117 (15) | −0.0103 (15) | −0.0099 (17) |
C34 | 0.0359 (14) | 0.0574 (14) | 0.0495 (17) | 0.0049 (13) | 0.0041 (13) | −0.0002 (10) |
C35 | 0.061 (2) | 0.0652 (16) | 0.0569 (16) | −0.0043 (17) | 0.0035 (18) | −0.0077 (14) |
C36 | 0.066 (2) | 0.100 (2) | 0.0559 (16) | −0.005 (2) | 0.0018 (19) | −0.0176 (17) |
C37 | 0.060 (2) | 0.125 (2) | 0.050 (2) | 0.002 (2) | 0.0022 (19) | 0.0067 (14) |
C38 | 0.0514 (18) | 0.093 (2) | 0.0668 (17) | 0.0095 (19) | 0.0094 (18) | 0.0248 (16) |
C39 | 0.0444 (16) | 0.0613 (14) | 0.0660 (17) | 0.0105 (14) | 0.0084 (16) | 0.0087 (14) |
C40 | 0.0483 (14) | 0.0616 (15) | 0.0416 (19) | 0.0010 (10) | 0.0076 (14) | 0.0062 (15) |
C41 | 0.0538 (14) | 0.0676 (16) | 0.058 (2) | −0.0038 (13) | 0.0069 (16) | 0.0028 (18) |
C42 | 0.0538 (14) | 0.095 (2) | 0.066 (3) | −0.0157 (15) | 0.0072 (18) | 0.005 (2) |
C43 | 0.0481 (17) | 0.119 (2) | 0.063 (3) | 0.0053 (13) | 0.0142 (18) | 0.013 (2) |
C44 | 0.0615 (15) | 0.093 (2) | 0.070 (3) | 0.0218 (15) | 0.015 (2) | 0.010 (2) |
C45 | 0.0595 (14) | 0.0641 (16) | 0.067 (3) | 0.0081 (13) | 0.0115 (18) | 0.0081 (18) |
C46 | 0.0545 (15) | 0.0440 (16) | 0.0599 (19) | 0.0040 (12) | 0.0037 (14) | −0.0047 (14) |
C47 | 0.072 (2) | 0.083 (3) | 0.070 (2) | 0.0053 (18) | 0.0111 (17) | −0.020 (2) |
C48 | 0.098 (3) | 0.096 (3) | 0.080 (3) | 0.012 (2) | −0.005 (2) | −0.038 (2) |
C49 | 0.102 (3) | 0.064 (2) | 0.104 (3) | −0.005 (2) | −0.022 (2) | −0.023 (2) |
C50 | 0.072 (2) | 0.066 (2) | 0.096 (3) | −0.0150 (17) | −0.0113 (19) | 0.002 (2) |
C51 | 0.0600 (17) | 0.0571 (19) | 0.067 (2) | −0.0048 (14) | 0.0018 (15) | 0.0026 (16) |
C52 | 0.124 (5) | 0.100 (4) | 0.094 (5) | 0.022 (3) | −0.042 (4) | −0.013 (3) |
C53 | 0.087 (4) | 0.142 (6) | 0.111 (6) | −0.021 (3) | −0.031 (4) | 0.005 (4) |
B1 | 0.0414 (17) | 0.0488 (19) | 0.048 (2) | 0.0026 (14) | 0.0048 (15) | 0.0023 (16) |
Cl1 | 0.261 (4) | 0.315 (5) | 0.0782 (15) | 0.095 (3) | −0.0274 (19) | −0.015 (2) |
Cl2 | 0.1225 (17) | 0.213 (3) | 0.342 (6) | 0.0025 (19) | −0.077 (3) | 0.004 (3) |
Cl3 | 0.1502 (17) | 0.1418 (17) | 0.143 (2) | −0.0151 (12) | 0.0490 (14) | −0.0088 (13) |
Cl4 | 0.1669 (18) | 0.1260 (14) | 0.0946 (13) | −0.0198 (12) | −0.0045 (12) | −0.0084 (10) |
N1 | 0.0494 (14) | 0.0403 (13) | 0.0480 (17) | −0.0017 (11) | −0.0037 (12) | 0.0004 (12) |
N2 | 0.0376 (12) | 0.0412 (13) | 0.0534 (18) | −0.0028 (10) | −0.0004 (11) | 0.0046 (12) |
C1—N2 | 1.297 (4) | C25—H25 | 0.9800 |
C1—N1 | 1.301 (4) | C26—H26A | 0.9600 |
C1—H1 | 0.9300 | C26—H26B | 0.9600 |
C2—N2 | 1.474 (4) | C26—H26C | 0.9600 |
C2—C3 | 1.526 (5) | C27—H27A | 0.9600 |
C2—H2A | 0.9700 | C27—H27B | 0.9600 |
C2—H2B | 0.9700 | C27—H27C | 0.9600 |
C3—N1 | 1.474 (4) | C28—C29 | 1.390 (6) |
C3—H3A | 0.9700 | C28—C33 | 1.386 (6) |
C3—H3B | 0.9700 | C28—B1 | 1.648 (5) |
C4—C9 | 1.391 (6) | C29—C30 | 1.393 (7) |
C4—C5 | 1.398 (6) | C29—H29 | 0.9300 |
C4—N2 | 1.441 (5) | C30—C31 | 1.372 (10) |
C5—C6 | 1.385 (6) | C30—H30 | 0.9300 |
C5—C10 | 1.514 (7) | C31—C32 | 1.340 (10) |
C6—C7 | 1.366 (7) | C31—H31 | 0.9300 |
C6—H6 | 0.9300 | C32—C33 | 1.407 (7) |
C7—C8 | 1.357 (7) | C32—H32 | 0.9300 |
C7—H7 | 0.9300 | C33—H33 | 0.9300 |
C8—C9 | 1.392 (6) | C34—C39 | 1.400 (5) |
C8—H8 | 0.9300 | C34—C35 | 1.403 (5) |
C9—C13 | 1.507 (7) | C34—B1 | 1.637 (6) |
C10—C12 | 1.509 (6) | C35—C36 | 1.384 (7) |
C10—C11 | 1.523 (9) | C35—H35 | 0.9300 |
C10—H10 | 0.9800 | C36—C37 | 1.367 (7) |
C11—H11A | 0.9600 | C36—H36 | 0.9300 |
C11—H11B | 0.9600 | C37—C38 | 1.362 (7) |
C11—H11C | 0.9600 | C37—H37 | 0.9300 |
C12—H12A | 0.9600 | C38—C39 | 1.378 (6) |
C12—H12B | 0.9600 | C38—H38 | 0.9300 |
C12—H12C | 0.9600 | C39—H39 | 0.9300 |
C13—C14 | 1.503 (8) | C40—C45 | 1.383 (5) |
C13—C15 | 1.536 (6) | C40—C41 | 1.390 (5) |
C13—H13 | 0.9800 | C40—B1 | 1.657 (5) |
C14—H14A | 0.9600 | C41—C42 | 1.400 (6) |
C14—H14B | 0.9600 | C41—H41 | 0.9300 |
C14—H14C | 0.9600 | C42—C43 | 1.352 (7) |
C15—H15A | 0.9600 | C42—H42 | 0.9300 |
C15—H15B | 0.9600 | C43—C44 | 1.350 (7) |
C15—H15C | 0.9600 | C43—H43 | 0.9300 |
C16—C17 | 1.381 (7) | C44—C45 | 1.403 (6) |
C16—C21 | 1.407 (7) | C44—H44 | 0.9300 |
C16—N1 | 1.452 (4) | C45—H45 | 0.9300 |
C17—C18 | 1.396 (6) | C46—C47 | 1.397 (6) |
C17—C25 | 1.514 (7) | C46—C51 | 1.397 (6) |
C18—C19 | 1.361 (8) | C46—B1 | 1.645 (5) |
C18—H18 | 0.9300 | C47—C48 | 1.401 (7) |
C19—C20 | 1.381 (7) | C47—H47 | 0.9300 |
C19—H19 | 0.9300 | C48—C49 | 1.344 (9) |
C20—C21 | 1.401 (6) | C48—H48 | 0.9300 |
C20—H20 | 0.9300 | C49—C50 | 1.362 (8) |
C21—C22 | 1.502 (7) | C49—H49 | 0.9300 |
C22—C23 | 1.513 (7) | C50—C51 | 1.389 (6) |
C22—C24 | 1.544 (6) | C50—H50 | 0.9300 |
C22—H22 | 0.9800 | C51—H51 | 0.9300 |
C23—H23A | 0.9600 | C52—Cl2 | 1.665 (8) |
C23—H23B | 0.9600 | C52—Cl1 | 1.699 (9) |
C23—H23C | 0.9600 | C52—H52B | 0.9700 |
C24—H24A | 0.9600 | C52—H52A | 0.9700 |
C24—H24B | 0.9600 | C53—Cl4 | 1.705 (8) |
C24—H24C | 0.9600 | C53—Cl3 | 1.739 (8) |
C25—C27 | 1.518 (8) | C53—H53B | 0.9700 |
C25—C26 | 1.530 (8) | C53—H53A | 0.9700 |
N2—C1—N1 | 114.2 (3) | C26—C25—H25 | 107.6 |
N2—C1—H1 | 122.9 | C25—C26—H26A | 109.5 |
N1—C1—H1 | 122.9 | C25—C26—H26B | 109.5 |
N2—C2—C3 | 103.1 (3) | H26A—C26—H26B | 109.5 |
N2—C2—H2A | 111.2 | C25—C26—H26C | 109.5 |
C3—C2—H2A | 111.2 | H26A—C26—H26C | 109.5 |
N2—C2—H2B | 111.2 | H26B—C26—H26C | 109.5 |
C3—C2—H2B | 111.2 | C25—C27—H27A | 109.5 |
H2A—C2—H2B | 109.1 | C25—C27—H27B | 109.5 |
N1—C3—C2 | 101.9 (2) | H27A—C27—H27B | 109.5 |
N1—C3—H3A | 111.4 | C25—C27—H27C | 109.5 |
C2—C3—H3A | 111.4 | H27A—C27—H27C | 109.5 |
N1—C3—H3B | 111.4 | H27B—C27—H27C | 109.5 |
C2—C3—H3B | 111.4 | C29—C28—C33 | 115.2 (4) |
H3A—C3—H3B | 109.2 | C29—C28—B1 | 122.5 (4) |
C9—C4—C5 | 123.2 (4) | C33—C28—B1 | 121.8 (4) |
C9—C4—N2 | 119.0 (3) | C28—C29—C30 | 122.7 (5) |
C5—C4—N2 | 117.5 (4) | C28—C29—H29 | 118.7 |
C6—C5—C4 | 116.9 (4) | C30—C29—H29 | 118.7 |
C6—C5—C10 | 120.6 (4) | C31—C30—C29 | 119.6 (6) |
C4—C5—C10 | 122.4 (4) | C31—C30—H30 | 120.2 |
C7—C6—C5 | 120.4 (4) | C29—C30—H30 | 120.2 |
C7—C6—H6 | 119.8 | C32—C31—C30 | 120.0 (5) |
C5—C6—H6 | 119.8 | C32—C31—H31 | 120.0 |
C8—C7—C6 | 122.0 (4) | C30—C31—H31 | 120.0 |
C8—C7—H7 | 119.0 | C31—C32—C33 | 120.3 (6) |
C6—C7—H7 | 119.0 | C31—C32—H32 | 119.9 |
C7—C8—C9 | 120.5 (4) | C33—C32—H32 | 119.9 |
C7—C8—H8 | 119.7 | C28—C33—C32 | 122.3 (5) |
C9—C8—H8 | 119.7 | C28—C33—H33 | 118.9 |
C8—C9—C4 | 116.8 (4) | C32—C33—H33 | 118.9 |
C8—C9—C13 | 120.1 (4) | C39—C34—C35 | 113.9 (4) |
C4—C9—C13 | 123.0 (3) | C39—C34—B1 | 123.6 (3) |
C12—C10—C5 | 113.6 (4) | C35—C34—B1 | 122.4 (3) |
C12—C10—C11 | 108.3 (5) | C36—C35—C34 | 123.3 (4) |
C5—C10—C11 | 110.5 (5) | C36—C35—H35 | 118.4 |
C12—C10—H10 | 108.1 | C34—C35—H35 | 118.4 |
C5—C10—H10 | 108.1 | C37—C36—C35 | 120.1 (5) |
C11—C10—H10 | 108.1 | C37—C36—H36 | 120.0 |
C10—C11—H11A | 109.5 | C35—C36—H36 | 120.0 |
C10—C11—H11B | 109.5 | C36—C37—C38 | 118.9 (5) |
H11A—C11—H11B | 109.5 | C36—C37—H37 | 120.6 |
C10—C11—H11C | 109.5 | C38—C37—H37 | 120.6 |
H11A—C11—H11C | 109.5 | C37—C38—C39 | 121.1 (4) |
H11B—C11—H11C | 109.5 | C37—C38—H38 | 119.5 |
C10—C12—H12A | 109.5 | C39—C38—H38 | 119.5 |
C10—C12—H12B | 109.5 | C38—C39—C34 | 122.8 (4) |
H12A—C12—H12B | 109.5 | C38—C39—H39 | 118.6 |
C10—C12—H12C | 109.5 | C34—C39—H39 | 118.6 |
H12A—C12—H12C | 109.5 | C45—C40—C41 | 115.2 (3) |
H12B—C12—H12C | 109.5 | C45—C40—B1 | 123.4 (3) |
C14—C13—C9 | 113.0 (4) | C41—C40—B1 | 121.2 (3) |
C14—C13—C15 | 111.9 (4) | C42—C41—C40 | 121.5 (4) |
C9—C13—C15 | 109.5 (4) | C42—C41—H41 | 119.2 |
C14—C13—H13 | 107.4 | C40—C41—H41 | 119.2 |
C9—C13—H13 | 107.4 | C43—C42—C41 | 121.8 (4) |
C15—C13—H13 | 107.4 | C43—C42—H42 | 119.1 |
C13—C14—H14A | 109.5 | C41—C42—H42 | 119.1 |
C13—C14—H14B | 109.5 | C44—C43—C42 | 117.9 (4) |
H14A—C14—H14B | 109.5 | C44—C43—H43 | 121.0 |
C13—C14—H14C | 109.5 | C42—C43—H43 | 121.0 |
H14A—C14—H14C | 109.5 | C43—C44—C45 | 121.3 (4) |
H14B—C14—H14C | 109.5 | C43—C44—H44 | 119.4 |
C13—C15—H15A | 109.5 | C45—C44—H44 | 119.4 |
C13—C15—H15B | 109.5 | C40—C45—C44 | 122.2 (4) |
H15A—C15—H15B | 109.5 | C40—C45—H45 | 118.9 |
C13—C15—H15C | 109.5 | C44—C45—H45 | 118.9 |
H15A—C15—H15C | 109.5 | C47—C46—C51 | 114.5 (4) |
H15B—C15—H15C | 109.5 | C47—C46—B1 | 122.7 (4) |
C17—C16—C21 | 123.7 (4) | C51—C46—B1 | 122.4 (4) |
C17—C16—N1 | 119.0 (4) | C48—C47—C46 | 121.3 (5) |
C21—C16—N1 | 117.2 (4) | C48—C47—H47 | 119.3 |
C16—C17—C18 | 117.3 (5) | C46—C47—H47 | 119.3 |
C16—C17—C25 | 122.6 (4) | C49—C48—C47 | 121.6 (5) |
C18—C17—C25 | 120.1 (5) | C49—C48—H48 | 119.2 |
C19—C18—C17 | 120.4 (5) | C47—C48—H48 | 119.2 |
C19—C18—H18 | 119.8 | C50—C49—C48 | 119.3 (5) |
C17—C18—H18 | 119.8 | C50—C49—H49 | 120.3 |
C18—C19—C20 | 122.2 (4) | C48—C49—H49 | 120.3 |
C18—C19—H19 | 118.9 | C49—C50—C51 | 119.6 (5) |
C20—C19—H19 | 118.9 | C49—C50—H50 | 120.2 |
C19—C20—C21 | 119.9 (5) | C51—C50—H50 | 120.2 |
C19—C20—H20 | 120.1 | C50—C51—C46 | 123.5 (5) |
C21—C20—H20 | 120.1 | C50—C51—H51 | 118.3 |
C20—C21—C16 | 116.5 (4) | C46—C51—H51 | 118.3 |
C20—C21—C22 | 120.8 (4) | Cl2—C52—Cl1 | 109.2 (4) |
C16—C21—C22 | 122.6 (3) | Cl2—C52—H52B | 109.8 |
C21—C22—C23 | 114.3 (4) | Cl1—C52—H52B | 109.8 |
C21—C22—C24 | 110.2 (4) | Cl2—C52—H52A | 109.8 |
C23—C22—C24 | 110.9 (4) | Cl1—C52—H52A | 109.8 |
C21—C22—H22 | 107.1 | H52B—C52—H52A | 108.3 |
C23—C22—H22 | 107.1 | Cl4—C53—Cl3 | 111.8 (3) |
C24—C22—H22 | 107.1 | Cl4—C53—H53B | 109.3 |
C22—C23—H23A | 109.5 | Cl3—C53—H53B | 109.3 |
C22—C23—H23B | 109.5 | Cl4—C53—H53A | 109.3 |
H23A—C23—H23B | 109.5 | Cl3—C53—H53A | 109.3 |
C22—C23—H23C | 109.5 | H53B—C53—H53A | 107.9 |
H23A—C23—H23C | 109.5 | C46—B1—C34 | 113.2 (3) |
H23B—C23—H23C | 109.5 | C46—B1—C28 | 102.5 (3) |
C22—C24—H24A | 109.5 | C34—B1—C28 | 112.2 (3) |
C22—C24—H24B | 109.5 | C46—B1—C40 | 113.2 (3) |
H24A—C24—H24B | 109.5 | C34—B1—C40 | 104.4 (3) |
C22—C24—H24C | 109.5 | C28—B1—C40 | 111.7 (3) |
H24A—C24—H24C | 109.5 | C1—N1—C16 | 125.6 (3) |
H24B—C24—H24C | 109.5 | C1—N1—C3 | 110.0 (3) |
C17—C25—C27 | 110.6 (5) | C16—N1—C3 | 123.9 (3) |
C17—C25—C26 | 113.3 (4) | C1—N2—C4 | 128.0 (3) |
C27—C25—C26 | 109.8 (5) | C1—N2—C2 | 109.3 (2) |
C17—C25—H25 | 107.6 | C4—N2—C2 | 122.0 (3) |
C27—C25—H25 | 107.6 |
Cg1, Cg2, Cg3 and Cg4 are the centroids defined by the ring atoms C28–C33, C34–C39, C40–C45 and C46–C51, respectively. |
D—H···A | D—H | H···A | D···A | D—H···A |
C3—H3A···Cg2 | 0.97 | 2.87 | 3.677 (4) | 141 |
C3—H3B···Cg3 | 0.97 | 2.75 | 3.562 (4) | 141 |
C52—H52A···Cg1i | 0.97 | 2.44 | 3.406 (7) | 171 |
C52—H52B···Cg4i | 0.97 | 2.62 | 3.434 (7) | 141 |
C53—H53A···Cg4ii | 0.97 | 2.88 | 3.818 (8) | 162 |
C53—H53B···Cg1 | 0.97 | 2.63 | 3.585 (8) | 169 |
Symmetry codes: (i) x−1/2, −y+3/2, z−1/2; (ii) x, y−1, z. |
Experimental details
Crystal data | |
Chemical formula | C27H39N2+·C24H20B−·2CH2Cl2 |
Mr | 880.66 |
Crystal system, space group | Monoclinic, Cc |
Temperature (K) | 296 |
a, b, c (Å) | 21.4648 (14), 10.3964 (7), 22.7524 (15) |
β (°) | 93.760 (1) |
V (Å3) | 5066.4 (6) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.27 |
Crystal size (mm) | 0.49 × 0.34 × 0.29 |
Data collection | |
Diffractometer | Bruker APEXII CCD |
Absorption correction | Multi-scan (SADABS; Bruker, 2010) |
Tmin, Tmax | 0.675, 0.746 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 17851, 8396, 7118 |
Rint | 0.013 |
(sin θ/λ)max (Å−1) | 0.617 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.062, 0.186, 1.35 |
No. of reflections | 8396 |
No. of parameters | 549 |
No. of restraints | 892 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.41, −0.44 |
Absolute structure | Flack (1983), 3456 Friedels |
Absolute structure parameter | −0.11 (10) |
Computer programs: APEX2 (Bruker, 2010), SAINT (Bruker, 2010), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997), SHELXTL (Sheldrick, 2008).
Cg1, Cg2, Cg3 and Cg4 are the centroids defined by the ring atoms C28–C33, C34–C39, C40–C45 and C46–C51, respectively. |
D—H···A | D—H | H···A | D···A | D—H···A |
C3—H3A···Cg2 | 0.97 | 2.87 | 3.677 (4) | 141 |
C3—H3B···Cg3 | 0.97 | 2.75 | 3.562 (4) | 141 |
C52—H52A···Cg1i | 0.97 | 2.44 | 3.406 (7) | 171 |
C52—H52B···Cg4i | 0.97 | 2.62 | 3.434 (7) | 141 |
C53—H53A···Cg4ii | 0.97 | 2.88 | 3.818 (8) | 162 |
C53—H53B···Cg1 | 0.97 | 2.63 | 3.585 (8) | 169 |
Symmetry codes: (i) x−1/2, −y+3/2, z−1/2; (ii) x, y−1, z. |
Acknowledgements
The authors would like to thank Saint Mary's University for providing funding in the form of initial operating funds, the Natural Sciences and Engineering Research Council for a Discovery Grant and a Research Tools and Instruments Grant (JDM), the Canadian Foundation for Innovation for a Leaders Opportunity Fund Grant, the Nova Scotia Research and Innovation Trust (JDM). Student funding was provided through the Saint Mary's University Summer Employment Experience Program (ADH) and the office of the Dean of Science Summer Research Award (NAG).
References
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Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
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Imidazolium and imidazolidinium cations are the essential precursors to neutral free carbene compounds in which a divalent carbon with a six-electron valence shell is electronically stabilized by donating amino-substituents and sterically protected by substituted phenyl groups. The title compound is related to the previously prepared 1,3-bis(2,6-diisopropylphenyl)imidazolidinium chloride. As a result of the increased steric bulk associated with the tetraphenylborate anion the title compound is the first reported structure in which the imidazolidinium C-2 hydrogen atom is not within the sum of the Van der Waals radii of any atom in the anion or co-crystalized solvent. The title compound can be compared to previously published structures (Arduengo et al., 1995, 1999; Fliedel et al., 2007; Hagos et al., 2008).
The asymmetric unit of the title compound is shown in Fig. 1. The crystal structure is stabilized by weak intermolecular C-H···π(arene) interactions.