research communications
of 1,4,8,11-tetramethyl-1,4,8,11-tetraazoniacyclotetradecane bis[chloridochromate(VI)] dichloride from synchrotron X-ray data
aBeamline Department, Pohang Accelerator Laboratory, POSTECH, Pohang 37673, Republic of Korea, and bDepartment of Chemistry, Andong National University, Andong 36729, Republic of Korea
*Correspondence e-mail: jhchoi@anu.ac.kr
The 14H36N4)[CrO3Cl]2Cl2, has been determined by synchrotron radiation X-ray crystallography at 220 K. The macrocyclic cation lies across a crystallographic inversion center and hence the contains one half of the organic cation, one chlorochromate anion and one chloride anion. Both the Cl− anion and chlorochromate Cl atom are involved in hydrogen bonding. In the crystal, hydrogen bonds involving the 1,4,8,11-tetramethyl-1,4,8,11-tetraazoniacyclotetradecane (TMC) N—H groups and C—H groups as donor groups and three O atoms of the chlorochromate and the chloride anion as acceptor groups link the components, giving rise to a three-dimensional network.
of title compound, (CKeywords: crystal structure; 1,4,8,11-tetramethyl-1,4,8,11-tetraazoniacyclotetradecane bis[chlorochromate(VI)] dichloride; hydrogen bonding; synchrotron radiation.
CCDC reference: 1988052
1. Chemical context
Chromium(VI) compounds have a toxic and genotoxic character to humans and wildlife (Yusof & Malek, 2009), but they are very important in industrial processes (Goyal et al., 2003). 1,4,8,11-Tetraazacyclotetradecane and its substituted derivatives are involved in diverse application fields such as catalysis, enzyme mimics, chemical sensors, selective metal-ion recovery, pharmacology and therapy (Meyer et al., 1998). Tetra-N-methylated 1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetradecane (TMC, C14H36N4) is basic and readily captures protons to form a dication, C14H34N42+, or tetracation, C14H36N44+, in which the N—H bonds are generally active in hydrogen-bond formation. These organic cations may be suitable for use in the removal of toxic metal ions.
Previously, the crystal structures of [H4TMC](ClO4)2Cl2 (Moon & Choi, 2020), [H2TMC][As4O2Cl10], [H2TMC][Sb2OCl6] (Willey et al., 1993), [H4TMC]2[Sb4F15][HF2]F4 (Becker & Mattes, 1996), [H4TMC][H2TMC][W(CN)8]2·4H2O (Nowicka et al., 2012) and [Al(CH3)]4[TMC] (Robinson et al., 1987) were determined, but there is no report of a compound with any combination of the 1,4,8,11-tetramethyl-1,4,8,11-tetraazoniacyclotetradecane cation and CrO3Cl− anion. In this communication, we report on the preparation of a new organic chlorochromate [H4TMC][CrO3Cl]2Cl2, (I), and its structural characterization by synchrotron single-crystal X-ray diffraction.
2. Structural commentary
The molecular structure of (I) is shown in Fig. 1 along with the atom-numbering scheme. The organic cation lies across a crystallographic inversion center and hence the contains one half of the organic cation, one chlorochromate(VI) anion and one chloride anion. The conformation of the tetracation in (I) (blue) is similar to that observed in [H4TMC](ClO4)2Cl2 (red) (Fig. 2; r.m.s. deviation overlay = 0.5878 Å), but it is different from the trans-I and trans-III conformations of the dications in [H2TMC][As4O2Cl10] and [H2TMC][Sb2OCl6], respectively (Willey et al., 1993). Within the centrosymmetric cation unit C14H36N44+, the C—C and N—C bond lengths vary from 1.520 (2) to 1.524 (2) Å and from 1.501 (2) to 1.513 (2) Å, respectively. The ranges of the N—C—C and C—N—C angles are 111.86 (15) to 116.39 (14)° and 108.81 (14) to 112.58 (14)°, respectively. The four nitrogen atoms of the macrocyclic cation are coplanar with the four nitrogens occupying the four corners of it with distances between each two N atoms of 3.2242 (13) Å (N1—N2), 5.414 (2) Å (N1—N1′) and 5.5907 (17) Å (N2—N2′), where the primed atoms are related by the (−x + 1, −y + 1, −z). The bond lengths and angles within the tetraammonium organic cation are comparable to the corresponding values determined for the H2TMC or H4TMC moiety in [H2TMC][As4O2Cl10], [H2TMC][Sb2OCl6] (Willey et al., 1993), [H4TMC](ClO4)2Cl2 (Moon & Choi, 2020), [H4TMC][H2TMC][W(CN)8]2·4H2O (Nowicka et al., 2012) and [H4TMC]2[Sb4F15][HF2]F4 (Becker & Mattes, 1996). The CrO3Cl− anion exhibits a more or less distorted tetrahedral geometry (Lorenzo Luis et al., 1996). The O—Cr—O angles range from 110.49 (14) to 111.22 (13)° and the O—Cr—Cl angles from 108.34 (8) to 109.69 (10)°. The Cr—O bond distances range from 1.588 (2) to 1.602 (2) Å and Cr—Cl bond length is 2.200 (1) Å, in good agreement with the values (2.197 and 2.194 Å) reported for Cs[CrO3Cl] and Rb[CrO3Cl] (Foster & Sterns, 1974).
3. Supramolecular features
Extensive C—H⋯O, C—H⋯Cl and N—H⋯Cl hydrogen-bonding interactions occur in the ). The organic C14H36N44+ cation is linked to two Cl− anions and one CrO3Cl− anion via N1—H1⋯Cl2, N2—H2⋯Cl2 and C4—H4C⋯O3 hydrogen bonds, respectively. In addition, three neighbouring organic cations are interconnected to the CrO3Cl− anion via several C—H⋯O hydrogen bonds (Fig. 3). The extensive array of these contacts generates a three-dimensional network and help to consolidate the The crystal packing diagram of (I) viewed perpendicular to the bc plane is shown in Fig. 4.
(Table 14. Database survey
A search of the Cambridge Structural Database (Version 5.41, November 2019; Groom et al., 2016) indicated only seven hits for organic compounds containing C14H32N4, C14H34N42+ or C14H36N44+ macrocycles: C14H32N4 (refcode LEPXOT; Willey et al., 1994), [Ga2(C3H7)4(OH)2](C14H32N4) (XEGGUL; Boag et al., 2000), Mg3Al13P16O64·1.5(C14H32N4)·2.5H2O (DAWQUN; Patinec et al., 1999), [C14H36N4]2[Sb4F15][HF2]F4 (ZITQUO; Becker et al., 1996), [C14H34N4][As4O2Cl10] (YALNII; Willey et al., 1993), [C14H34N4][Sb2OCl6] (YALNEE; Willey et al., 1993) and [C14H36N4][C14H34N4][W(CN)8]2·4H2O (ACIKUU; Nowicka et al., 2012). The conformation of the organic C14H36N44+ cation in (I) is comparable to the trans-IV, trans-I and trans-III conformations of the macrocyclic cations in [C14H36N4](ClO4)2Cl2 (GUCVAE; Moon & Choi, 2020), [C14H34N4][As4O2Cl10] (YALNII), and [C14H34N4][Sb2OCl6] (YALNEE), respectively. The trans-III and trans-IV conformations observed in the two crystallographically independent molecules of C14H32N4 were also comparable (Willey et al., 1994). However, the compound and structure of any double salt of C14H36N44+ with an additional CrClO3− anion is not yet known.
5. Synthesis and crystallization
The free macrocycle TMC (98%) and chromium(VI) trioxide (99%) were purchased from Sigma–Aldrich and used without further purification. All other chemicals were reagent-grade materials and used as received. To a solution of TMC (0.128 g, 0.5 mmol) in 6 M HCl (15 mL) was added a solution of chromium(VI) trioxide (0.1 g, 1 mmol) in 6 M HCl (5 mL) at 298 K. The resulting solution was stirred for 2 h and left to stand for slow evaporation at room temperature. Block-like red single crystals of (I) suitable for X-ray analysis were obtained by filtration.
6. Refinement
Crystal data, data collection and structure . All H atoms were placed in geometrically idealized positions and constrained to ride on their parent atoms, with C—H = 0.97–0.98 Å and N—H = 0.99 Å, respectively, and with Uiso(H) values of 1.5 and 1.2Ueq of the parent atoms.
details are summarized in Table 2
|
Supporting information
CCDC reference: 1988052
https://doi.org/10.1107/S2056989020003059/vm2229sup1.cif
contains datablock I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989020003059/vm2229Isup2.hkl
Data collection: PAL BL2D-SMDC (Shin et al., 2016); cell
HKL3000sm (Otwinowski & Minor, 1997); data reduction: HKL3000sm (Otwinowski & Minor, 1997); program(s) used to solve structure: SHELXT2018 (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2018 (Sheldrick, 2015b); molecular graphics: DIAMOND4 (Putz & Brandenburg, 2014); software used to prepare material for publication: publCIF (Westrip, 2010).(C14H36N4)[CrO3Cl]2Cl2 | Z = 1 |
Mr = 602.27 | F(000) = 312 |
Triclinic, P1 | Dx = 1.579 Mg m−3 |
a = 7.0610 (14) Å | Synchrotron radiation, λ = 0.610 Å |
b = 8.6740 (17) Å | Cell parameters from 41622 reflections |
c = 10.775 (2) Å | θ = 0.4–33.7° |
α = 77.61 (3)° | µ = 0.85 mm−1 |
β = 88.20 (3)° | T = 220 K |
γ = 79.39 (3)° | Block, red |
V = 633.5 (2) Å3 | 0.21 × 0.15 × 0.11 mm |
Rayonix MX225HS CCD area detector diffractometer | 3357 reflections with I > 2σ(I) |
Radiation source: PLSII 2D bending magnet | Rint = 0.022 |
ω scan | θmax = 25.0°, θmin = 1.7° |
Absorption correction: empirical (using intensity measurements) (HKL3000sm Scalepack; Otwinowski & Minor, 1997) | h = −9→9 |
Tmin = 0.552, Tmax = 1.000 | k = −12→12 |
6933 measured reflections | l = −14→14 |
3503 independent reflections |
Refinement on F2 | 0 restraints |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.050 | H-atom parameters constrained |
wR(F2) = 0.150 | w = 1/[σ2(Fo2) + (0.1021P)2 + 0.4428P] where P = (Fo2 + 2Fc2)/3 |
S = 1.08 | (Δ/σ)max < 0.001 |
3503 reflections | Δρmax = 0.81 e Å−3 |
138 parameters | Δρmin = −1.08 e Å−3 |
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes. |
x | y | z | Uiso*/Ueq | ||
N1 | 0.5951 (2) | 0.43908 (19) | 0.24944 (14) | 0.0197 (3) | |
H1 | 0.655924 | 0.528759 | 0.203398 | 0.024* | |
N2 | 0.3111 (2) | 0.75634 (17) | 0.10259 (15) | 0.0178 (3) | |
H2 | 0.448197 | 0.736710 | 0.077822 | 0.021* | |
C1 | 0.8079 (3) | 0.1708 (2) | 0.01696 (18) | 0.0203 (3) | |
H1A | 0.942223 | 0.140900 | −0.007767 | 0.024* | |
H1AB | 0.763915 | 0.071671 | 0.058488 | 0.024* | |
C2 | 0.8030 (2) | 0.2755 (2) | 0.11389 (17) | 0.0202 (3) | |
H2A | 0.850838 | 0.373545 | 0.074404 | 0.024* | |
H2AB | 0.889395 | 0.217967 | 0.184918 | 0.024* | |
C3 | 0.6013 (3) | 0.3211 (2) | 0.16488 (18) | 0.0216 (3) | |
H3A | 0.511705 | 0.368064 | 0.093415 | 0.026* | |
H3AB | 0.559012 | 0.224125 | 0.212911 | 0.026* | |
C4 | 0.7083 (4) | 0.3635 (3) | 0.3696 (2) | 0.0350 (5) | |
H4A | 0.710246 | 0.443738 | 0.419628 | 0.052* | |
H4B | 0.839127 | 0.320257 | 0.348638 | 0.052* | |
H4C | 0.648561 | 0.277582 | 0.418098 | 0.052* | |
C5 | 0.3917 (3) | 0.5084 (2) | 0.28166 (17) | 0.0214 (3) | |
H5A | 0.398383 | 0.581772 | 0.338417 | 0.026* | |
H5AB | 0.331618 | 0.420559 | 0.329015 | 0.026* | |
C6 | 0.2612 (2) | 0.5985 (2) | 0.16973 (17) | 0.0191 (3) | |
H6A | 0.265642 | 0.529620 | 0.108100 | 0.023* | |
H6AB | 0.128516 | 0.617792 | 0.200171 | 0.023* | |
C7 | 0.2870 (3) | 0.8760 (2) | 0.1871 (2) | 0.0287 (4) | |
H7A | 0.309296 | 0.978749 | 0.138299 | 0.043* | |
H7B | 0.378911 | 0.838265 | 0.256843 | 0.043* | |
H7C | 0.157143 | 0.888100 | 0.220467 | 0.043* | |
Cr1 | 0.20005 (5) | 0.19152 (4) | 0.58525 (3) | 0.02581 (14) | |
Cl1 | 0.21038 (11) | 0.11680 (9) | 0.40216 (7) | 0.04726 (19) | |
O1 | 0.2178 (4) | 0.0382 (3) | 0.6983 (2) | 0.0578 (6) | |
O2 | 0.0005 (3) | 0.3102 (3) | 0.59266 (19) | 0.0461 (5) | |
O3 | 0.3790 (3) | 0.2812 (3) | 0.5855 (2) | 0.0459 (5) | |
Cl2 | 0.74460 (6) | 0.71108 (6) | 0.05475 (5) | 0.02599 (15) |
U11 | U22 | U33 | U12 | U13 | U23 | |
N1 | 0.0203 (7) | 0.0201 (7) | 0.0179 (6) | −0.0016 (5) | −0.0003 (5) | −0.0042 (5) |
N2 | 0.0161 (6) | 0.0139 (6) | 0.0231 (7) | −0.0019 (5) | 0.0036 (5) | −0.0049 (5) |
C1 | 0.0175 (7) | 0.0155 (7) | 0.0252 (8) | 0.0018 (6) | 0.0016 (6) | −0.0024 (6) |
C2 | 0.0168 (7) | 0.0194 (8) | 0.0226 (8) | −0.0002 (6) | 0.0009 (6) | −0.0030 (6) |
C3 | 0.0189 (8) | 0.0223 (8) | 0.0244 (8) | −0.0023 (6) | 0.0029 (6) | −0.0085 (6) |
C4 | 0.0384 (12) | 0.0407 (12) | 0.0216 (9) | 0.0067 (9) | −0.0102 (8) | −0.0078 (8) |
C5 | 0.0220 (8) | 0.0216 (8) | 0.0192 (7) | −0.0018 (6) | 0.0050 (6) | −0.0038 (6) |
C6 | 0.0174 (7) | 0.0155 (7) | 0.0239 (8) | −0.0034 (5) | 0.0041 (6) | −0.0030 (6) |
C7 | 0.0381 (11) | 0.0196 (8) | 0.0312 (9) | −0.0048 (7) | 0.0047 (8) | −0.0124 (7) |
Cr1 | 0.0292 (2) | 0.0227 (2) | 0.0242 (2) | −0.00618 (13) | 0.00070 (13) | −0.00076 (13) |
Cl1 | 0.0520 (4) | 0.0530 (4) | 0.0450 (4) | −0.0119 (3) | 0.0076 (3) | −0.0274 (3) |
O1 | 0.0855 (18) | 0.0349 (10) | 0.0450 (11) | −0.0130 (10) | −0.0045 (11) | 0.0111 (8) |
O2 | 0.0433 (10) | 0.0534 (11) | 0.0367 (9) | 0.0066 (9) | 0.0027 (7) | −0.0126 (8) |
O3 | 0.0468 (11) | 0.0535 (12) | 0.0454 (10) | −0.0246 (9) | −0.0010 (8) | −0.0141 (9) |
Cl2 | 0.0172 (2) | 0.0255 (2) | 0.0356 (3) | −0.00824 (16) | 0.00510 (17) | −0.00431 (19) |
N1—C4 | 1.501 (2) | C4—H4A | 0.9700 |
N1—C3 | 1.503 (2) | C4—H4B | 0.9700 |
N1—C5 | 1.511 (2) | C4—H4C | 0.9700 |
N1—H1 | 0.9900 | C5—C6 | 1.521 (3) |
N2—C6 | 1.503 (2) | C5—H5A | 0.9800 |
N2—C7 | 1.505 (2) | C5—H5AB | 0.9800 |
N2—C1i | 1.513 (2) | C6—H6A | 0.9800 |
N2—H2 | 0.9900 | C6—H6AB | 0.9800 |
C1—C2 | 1.520 (3) | C7—H7A | 0.9700 |
C1—H1A | 0.9800 | C7—H7B | 0.9700 |
C1—H1AB | 0.9800 | C7—H7C | 0.9700 |
C2—C3 | 1.524 (2) | Cr1—O1 | 1.588 (2) |
C2—H2A | 0.9800 | Cr1—O2 | 1.596 (2) |
C2—H2AB | 0.9800 | Cr1—O3 | 1.602 (2) |
C3—H3A | 0.9800 | Cr1—Cl1 | 2.2000 (9) |
C3—H3AB | 0.9800 | ||
C4—N1—C3 | 110.93 (15) | N1—C4—H4A | 109.5 |
C4—N1—C5 | 109.63 (15) | N1—C4—H4B | 109.5 |
C3—N1—C5 | 112.58 (14) | H4A—C4—H4B | 109.5 |
C4—N1—H1 | 107.8 | N1—C4—H4C | 109.5 |
C3—N1—H1 | 107.8 | H4A—C4—H4C | 109.5 |
C5—N1—H1 | 107.8 | H4B—C4—H4C | 109.5 |
C6—N2—C7 | 112.00 (15) | N1—C5—C6 | 116.12 (14) |
C6—N2—C1i | 112.21 (14) | N1—C5—H5A | 108.3 |
C7—N2—C1i | 108.81 (14) | C6—C5—H5A | 108.3 |
C6—N2—H2 | 107.9 | N1—C5—H5AB | 108.3 |
C7—N2—H2 | 107.9 | C6—C5—H5AB | 108.3 |
C1i—N2—H2 | 107.9 | H5A—C5—H5AB | 107.4 |
N2i—C1—C2 | 116.39 (14) | N2—C6—C5 | 115.04 (15) |
N2i—C1—H1A | 108.2 | N2—C6—H6A | 108.5 |
C2—C1—H1A | 108.2 | C5—C6—H6A | 108.5 |
N2i—C1—H1AB | 108.2 | N2—C6—H6AB | 108.5 |
C2—C1—H1AB | 108.2 | C5—C6—H6AB | 108.5 |
H1A—C1—H1AB | 107.3 | H6A—C6—H6AB | 107.5 |
C1—C2—C3 | 112.61 (15) | N2—C7—H7A | 109.5 |
C1—C2—H2A | 109.1 | N2—C7—H7B | 109.5 |
C3—C2—H2A | 109.1 | H7A—C7—H7B | 109.5 |
C1—C2—H2AB | 109.1 | N2—C7—H7C | 109.5 |
C3—C2—H2AB | 109.1 | H7A—C7—H7C | 109.5 |
H2A—C2—H2AB | 107.8 | H7B—C7—H7C | 109.5 |
N1—C3—C2 | 111.86 (15) | O1—Cr1—O2 | 110.49 (14) |
N1—C3—H3A | 109.2 | O1—Cr1—O3 | 111.05 (14) |
C2—C3—H3A | 109.2 | O2—Cr1—O3 | 111.22 (13) |
N1—C3—H3AB | 109.2 | O1—Cr1—Cl1 | 109.69 (10) |
C2—C3—H3AB | 109.2 | O2—Cr1—Cl1 | 108.34 (8) |
H3A—C3—H3AB | 107.9 | O3—Cr1—Cl1 | 105.90 (9) |
N2i—C1—C2—C3 | 61.3 (2) | C3—N1—C5—C6 | −59.5 (2) |
C4—N1—C3—C2 | −67.1 (2) | C7—N2—C6—C5 | −64.42 (19) |
C5—N1—C3—C2 | 169.64 (15) | C1i—N2—C6—C5 | 172.85 (14) |
C1—C2—C3—N1 | −173.71 (14) | N1—C5—C6—N2 | −69.9 (2) |
C4—N1—C5—C6 | 176.52 (17) |
Symmetry code: (i) −x+1, −y+1, −z. |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1···Cl2 | 0.99 | 2.16 | 3.120 (2) | 163 |
N2—H2···Cl2 | 0.99 | 2.08 | 3.0553 (17) | 170 |
C2—H2A···Cl2 | 0.98 | 2.85 | 3.642 (2) | 139 |
C4—H4C···O3 | 0.97 | 2.58 | 3.299 (4) | 131 |
C5—H5AB···Cl1 | 0.98 | 2.86 | 3.804 (2) | 161 |
C3—H3A···Cl2i | 0.98 | 2.72 | 3.541 (2) | 142 |
C1—H1A···Cl2ii | 0.98 | 2.74 | 3.511 (2) | 136 |
C1—H1AB···O1iii | 0.98 | 2.59 | 3.230 (3) | 123 |
C2—H2AB···O1iii | 0.98 | 2.54 | 3.047 (3) | 112 |
C3—H3AB···O1iii | 0.98 | 2.53 | 3.193 (3) | 125 |
C4—H4A···O3iv | 0.97 | 2.34 | 3.168 (3) | 143 |
C5—H5A···O3iv | 0.98 | 2.40 | 3.218 (3) | 141 |
C7—H7B···O3iv | 0.97 | 2.38 | 3.343 (3) | 173 |
C4—H4B···Cl1v | 0.97 | 2.88 | 3.773 (3) | 154 |
C6—H6AB···O2vi | 0.98 | 2.54 | 3.260 (3) | 130 |
Symmetry codes: (i) −x+1, −y+1, −z; (ii) −x+2, −y+1, −z; (iii) −x+1, −y, −z+1; (iv) −x+1, −y+1, −z+1; (v) x+1, y, z; (vi) −x, −y+1, −z+1. |
Funding information
This work was supported by a Research Grant from Andong National University. The X-ray crystallography experiment at PLS-II BL2D-SMC beamline was supported in part by MSIT and POSTECH.
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