research communications
of 1,4,8,11-tetramethyl-1,4,8,11-tetraazoniacyclotetradecane bis(perchlorate) 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 14H36N44+·2ClO4−·2Cl−, has been determined using synchrotron radiation at 220 K. The reveals that protonation has occurred at all four amine N atoms. The contains one half-cation (completed by crystallographic inversion symmetry), one perchlorate anion and one chloride anion. A distortion of the perchlorate anion is due to its involvement in hydrogen-bonding interactions with the cations. The is consolidated by intermolecular hydrogen bonds involving the 1,4,8,11-tetramethyl-1,4,8,11-tetraazoniacyclotetradecane N—H and C—H groups as donor groups, and the O atoms of the perchlorate and chloride anion as acceptor groups, giving rise to a three-dimensional network.
of title salt, CKeywords: crystal structure; 1,4,8,11-tetramethyl-1,4,8,11-tetraazoniacyclotetradecane; bis(perchlorate) dichloride; hydrogen bonding; synchrotron radiation.
CCDC reference: 1980910
1. Chemical context
Tetraazamacrocycle 1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetradecane (TMC, C14H32N4) is one of the most useful azamacrocycles because of its ability to act as an effective metal-ion binding site and its basic properties. N-Substituted TMC is a basic amine that may form a dication, C14H34N42+, or a tetracation, C14H36N44+, in which the N—H bonds are generally active in hydrogen-bond formation. These di- or tetraammonium cations may be suitable for the removal of toxic heavy-metal ions. Because of a difference in the of the secondary NH centers, the macrocyclic compounds can exhibit five conformations, viz. trans-I (RSRS), trans-II (RSRR), trans-III (RRSS), trans-IV (SRRS) and trans-V (RRRR) (Choi, 2009). Previously, the crystal structures for trans-[Ni(TMC)(H2O)2]Cl2·2H2O, [Ni(TMC)](O3SCF3) (Barefield et al., 1986), [Cu(TMC)(H2O)](ClO4)2·H2O (Lee et al., 1986), [Cu(TMC)](ClO4)2 (Maimon et al., 2001), [Ag(TMC)](ClO4)2 (Po et al., 1991), [Cu(NCS)(TMC)]ClO4 (Lu et al., 1998) and [Cu(TMC)](BF4)2 (Bucher et al., 2001b) have been characterized crystallographically. In addition, first-row transition-metal complexes of the form [MIICl(TMC)]+ [M = Zn (Alcock et al., 1978), Mn (Bucher et al., 2001a), Ni (Nishigaki et al., 2010), Fe (Bedford et al., 2016) and Co (Van Heuvelen et al., 2017)] have been determined. Two independent ring conformations, trans-III and trans-IV, in the of free TMC were also found (Willey et al., 1994), but there is no report of a structure with any combination of the 1,4,8,11-tetramethyl-1,4,8,11-tetraazoniacyclotetradecane cation and ClO4− and Cl− anions. We report here the preparation of a new compound [H4TMC](ClO4)2Cl2, (I), and its structural characterization by synchrotron single-crystal X-ray diffraction.
2. Structural commentary
An ellipsoid plot of the molecular components in (I) is shown in Fig. 1 along with the atom-numbering scheme. The consists of one half of the macrocycle, which lies about a center of inversion, one perchlorate anion and one chloride anion. The tetra-protonated amine of the title compound has a distorted trans-IV conformation, which is comparable to the trans-I or trans-III conformations of the dications in [H2TMC][As4O2Cl10] and [H2TMC][Sb2OCl6], respectively (Willey et al., 1993). Within the centrosymmetric tetra-protonated C14H36N44+ amine unit, the C—C and N—C bond lengths vary from 1.522 (2) to 1.527 (2) Å and from 1.5033 (19) to 1.5181 (18) Å, respectively. The N—C—C and C—N—C angles range from 113.55 (12) to 116.19 (12)° and 108.49 (12) to 112.37 (11)°, respectively. The bond lengths and angles within the tetraammonium cations are comparable to the corresponding values determined for the TMC moiety in [H4TMC]2[Sb4F15][HF2]F4 (Becker & Mattes, 1996), [H2TMC][As4O2Cl10], [H2TMC][Sb2OCl6] (Willey et al., 1993), [H4TMC][H2TMC][W(CN)8]2·4H2O (Nowicka et al., 2012), [Ga2(C3H7)4(OH)2](TMC) (Boag et al., 2000), TMC (Willey et al., 1994), trans-[Ni(TMC)(H2O)2]Cl2·2H2O (Barefield et al., 1986), trans-[Os(TMC)(O)2](PF6)2 (Kelly et al., 1996), [Cu(TMC)(H2O)](ClO4)2·H2O (Lee et al., 1986), [Cu(NCS)(TMC)]ClO4 (Lu et al., 1998) and [Cu(TMC)](BF4)2 (Bucher et al., 2001b). The Cl—O bond distances in the tetrahedral ClO4− anion range from 1.4180 (17) to 1.4380 (16) Å and the O—Cl—O angles from 106.85 (14)–110.94 (12)°. A distortion of the ClO4− anion undoubtedly results from its involvement in hydrogen-bonding interactions with the cations.
3. Supramolecular features
Extensive N—H⋯Cl, C—H⋯Cl and C—H⋯O hydrogen-bonding interactions occur in the ). A crystal packing diagram of (I) viewed perpendicular to the ab plane is shown in Fig. 2.
(Table 1The N—H⋯Cl and C—H⋯Cl hydrogen bonds link the two Cl− anions to the C14H36N44+ cation while C—H⋯O hydrogen bonds interconnect neighboring cations with the ClO4− anions. An extensive array of these contacts generates a three-dimensional network of molecules, and these hydrogen-bonding interactions help to consolidate the crystal structure.
4. Database survey
A search of the Cambridge Structural Database (Version 5.41, November 2019; Groom et al., 2016) gave just seven hits for organic compounds containing C14H36N44+, C14H34N42+ or C14H32N4 macrocycles: [C14H36N4]2[Sb4F15][HF2]F4 (Becker et al., 1996), [C14H34N4][As4O2Cl10] and [C14H34N4][Sb2OCl6] (Willey et al., 1993), [C14H36N4][C14H34N4][W(CN)8]2·4H2O (Nowicka et al., 2012), [Ga2(C3H7)4(OH)2](C14H32N4) (Boag et al., 2000) and (C14H32N4) (Willey et al., 1994). However, the of the title compound had not been deposited until now. The tetra-protonated amine of the title compound has a trans-IV conformation, which is comparable to the trans-I or trans-III conformation of the dications in [H2TMC][As4O2Cl10] and [H2TMC][Sb2OCl6], respectively (Willey et al., 1993).
5. Synthesis and crystallization
The free ligand TMC (98%) was purchased from Sigma–Aldrich and used without further purification. All chemicals were reagent grade materials, and were used as received. TMC (0.128 g, 0.5 mmol) was dissolved in 15 mL of 6 M HCl, and 5 mL of a of sodium perchlorate including chromium trioxide (0.1 g, 1 mmol) was added to the resulting solution at 298 K. The mixture was stirred for 2 h and the solution was filtered. Block-like pale yellow crystals of (I) suitable for X-ray structural analysis were unexpectedly obtained from the solution at 298 K over a period of a few days.
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, and with Uiso(H) values of 1.5 and 1.2 times the Ueq of the parent atoms.
details are summarized in Table 2
|
Supporting information
CCDC reference: 1980910
https://doi.org/10.1107/S2056989020001322/vm2227sup1.cif
contains datablock I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989020001322/vm2227Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S2056989020001322/vm2227Isup3.cml
Data collection: PAL BL2D-SMDC Program (Shin et al., 2016); cell
HKL3000sm (Otwinowski & Minor, 1997); data reduction: HKL3000sm (Otwinowski & Minor, 1997); program(s) used to solve structure: SHELXT2014 (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).C14H36N44+·2ClO4−·2Cl− | Z = 1 |
Mr = 530.27 | F(000) = 280 |
Triclinic, P1 | Dx = 1.533 Mg m−3 |
a = 7.4990 (15) Å | Synchrotron radiation, λ = 0.610 Å |
b = 8.0790 (16) Å | Cell parameters from 91694 reflections |
c = 9.980 (2) Å | θ = 0.4–33.7° |
α = 81.31 (3)° | µ = 0.36 mm−1 |
β = 77.32 (3)° | T = 220 K |
γ = 78.39 (3)° | Block, pale yellow |
V = 574.2 (2) Å3 | 0.10 × 0.10 × 0.08 mm |
Rayonix MX225HS CCD area detector diffractometer | 3208 reflections with I > 2σ(I) |
Radiation source: PLSII 2D bending magnet | Rint = 0.038 |
ω scan | θmax = 25.5°, θmin = 1.8° |
Absorption correction: empirical (using intensity measurements) (HKL3000sm Scalepack; Otwinowski & Minor, 1997) | h = −10→10 |
Tmin = 0.710, Tmax = 1.000 | k = −11→11 |
6573 measured reflections | l = −14→14 |
3361 independent reflections |
Refinement on F2 | 0 restraints |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.052 | H-atom parameters constrained |
wR(F2) = 0.147 | w = 1/[σ2(Fo2) + (0.1013P)2 + 0.2815P] where P = (Fo2 + 2Fc2)/3 |
S = 1.05 | (Δ/σ)max = 0.001 |
3361 reflections | Δρmax = 0.97 e Å−3 |
138 parameters | Δρmin = −0.56 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 | 0.67545 (16) | 0.40154 (15) | 0.21687 (13) | 0.0182 (2) | |
H1 | 0.702337 | 0.480395 | 0.131812 | 0.022* | |
N2 | 0.32976 (16) | 0.70943 (15) | 0.15397 (13) | 0.0187 (2) | |
H2 | 0.447969 | 0.698634 | 0.085623 | 0.022* | |
C1 | 0.82761 (19) | 0.26947 (19) | −0.07624 (16) | 0.0213 (3) | |
H1A | 0.844476 | 0.382168 | −0.061678 | 0.026* | |
H1AB | 0.942570 | 0.216566 | −0.133336 | 0.026* | |
C2 | 0.7951 (2) | 0.16181 (18) | 0.06343 (16) | 0.0222 (3) | |
H2A | 0.911494 | 0.135809 | 0.097951 | 0.027* | |
H2AB | 0.766041 | 0.053719 | 0.048851 | 0.027* | |
C3 | 0.6416 (2) | 0.24003 (18) | 0.17554 (15) | 0.0202 (3) | |
H3A | 0.524235 | 0.264324 | 0.142544 | 0.024* | |
H3AB | 0.628253 | 0.156392 | 0.257539 | 0.024* | |
C4 | 0.8394 (2) | 0.3698 (2) | 0.2869 (2) | 0.0289 (3) | |
H4A | 0.852000 | 0.474931 | 0.316837 | 0.043* | |
H4B | 0.951096 | 0.328712 | 0.222555 | 0.043* | |
H4C | 0.820747 | 0.285389 | 0.366416 | 0.043* | |
C5 | 0.5084 (2) | 0.48877 (19) | 0.31152 (15) | 0.0219 (3) | |
H5A | 0.541977 | 0.588041 | 0.339066 | 0.026* | |
H5AB | 0.480340 | 0.410569 | 0.395386 | 0.026* | |
C6 | 0.3326 (2) | 0.54741 (19) | 0.25240 (16) | 0.0220 (3) | |
H6A | 0.315943 | 0.456530 | 0.203864 | 0.026* | |
H6AB | 0.226499 | 0.564160 | 0.329274 | 0.026* | |
C7 | 0.3152 (2) | 0.8628 (2) | 0.22684 (18) | 0.0267 (3) | |
H7A | 0.305431 | 0.964466 | 0.161379 | 0.040* | |
H7B | 0.424822 | 0.852681 | 0.266082 | 0.040* | |
H7C | 0.205791 | 0.870354 | 0.300087 | 0.040* | |
Cl1 | 0.21029 (5) | 0.17202 (5) | 0.52791 (4) | 0.02439 (13) | |
O1 | 0.2471 (3) | 0.1745 (2) | 0.38061 (17) | 0.0494 (4) | |
O2 | 0.1539 (3) | 0.0175 (3) | 0.5935 (3) | 0.0669 (6) | |
O3 | 0.3753 (3) | 0.1946 (3) | 0.5690 (2) | 0.0560 (5) | |
O4 | 0.0647 (3) | 0.3129 (3) | 0.5618 (3) | 0.0662 (6) | |
Cl2 | 0.73888 (5) | 0.71235 (4) | 0.00536 (4) | 0.02198 (13) |
U11 | U22 | U33 | U12 | U13 | U23 | |
N1 | 0.0174 (5) | 0.0170 (5) | 0.0224 (5) | −0.0036 (4) | −0.0087 (4) | −0.0011 (4) |
N2 | 0.0150 (5) | 0.0180 (5) | 0.0242 (5) | −0.0023 (4) | −0.0058 (4) | −0.0042 (4) |
C1 | 0.0144 (6) | 0.0238 (6) | 0.0281 (7) | −0.0034 (5) | −0.0074 (5) | −0.0056 (5) |
C2 | 0.0200 (6) | 0.0181 (6) | 0.0301 (7) | 0.0004 (5) | −0.0105 (5) | −0.0041 (5) |
C3 | 0.0201 (6) | 0.0175 (6) | 0.0263 (6) | −0.0051 (5) | −0.0095 (5) | −0.0026 (5) |
C4 | 0.0247 (7) | 0.0285 (8) | 0.0402 (8) | −0.0049 (6) | −0.0196 (6) | −0.0047 (6) |
C5 | 0.0237 (6) | 0.0216 (6) | 0.0213 (6) | −0.0028 (5) | −0.0066 (5) | −0.0032 (5) |
C6 | 0.0183 (6) | 0.0193 (6) | 0.0278 (7) | −0.0035 (5) | −0.0043 (5) | −0.0012 (5) |
C7 | 0.0304 (8) | 0.0198 (7) | 0.0346 (8) | −0.0038 (5) | −0.0133 (6) | −0.0085 (6) |
Cl1 | 0.0237 (2) | 0.0222 (2) | 0.0294 (2) | −0.00633 (14) | −0.00871 (15) | −0.00105 (14) |
O1 | 0.0545 (10) | 0.0648 (11) | 0.0346 (7) | −0.0209 (8) | −0.0060 (7) | −0.0131 (7) |
O2 | 0.0720 (13) | 0.0481 (10) | 0.0887 (15) | −0.0350 (9) | −0.0404 (12) | 0.0356 (10) |
O3 | 0.0533 (10) | 0.0629 (11) | 0.0691 (12) | −0.0267 (9) | −0.0400 (9) | 0.0023 (9) |
O4 | 0.0504 (10) | 0.0561 (11) | 0.0837 (15) | 0.0128 (9) | −0.0007 (10) | −0.0290 (10) |
Cl2 | 0.01828 (19) | 0.0202 (2) | 0.0293 (2) | −0.00692 (13) | −0.00735 (14) | 0.00056 (13) |
N1—C4 | 1.5037 (19) | C4—H4A | 0.9700 |
N1—C3 | 1.5095 (18) | C4—H4B | 0.9700 |
N1—C5 | 1.5116 (19) | C4—H4C | 0.9700 |
N1—H1 | 0.9900 | C5—C6 | 1.522 (2) |
N2—C7 | 1.5033 (19) | C5—H5A | 0.9800 |
N2—C6 | 1.513 (2) | C5—H5AB | 0.9800 |
N2—C1i | 1.5181 (18) | C6—H6A | 0.9800 |
N2—H2 | 0.9900 | C6—H6AB | 0.9800 |
C1—C2 | 1.526 (2) | C7—H7A | 0.9700 |
C1—H1A | 0.9800 | C7—H7B | 0.9700 |
C1—H1AB | 0.9800 | C7—H7C | 0.9700 |
C2—C3 | 1.527 (2) | Cl1—O2 | 1.4180 (17) |
C2—H2A | 0.9800 | Cl1—O1 | 1.4328 (16) |
C2—H2AB | 0.9800 | Cl1—O4 | 1.4342 (19) |
C3—H3A | 0.9800 | Cl1—O3 | 1.4380 (16) |
C3—H3AB | 0.9800 | ||
C4—N1—C3 | 111.91 (12) | N1—C4—H4A | 109.5 |
C4—N1—C5 | 108.49 (12) | N1—C4—H4B | 109.5 |
C3—N1—C5 | 112.37 (11) | H4A—C4—H4B | 109.5 |
C4—N1—H1 | 108.0 | N1—C4—H4C | 109.5 |
C3—N1—H1 | 108.0 | H4A—C4—H4C | 109.5 |
C5—N1—H1 | 108.0 | H4B—C4—H4C | 109.5 |
C7—N2—C6 | 112.12 (12) | N1—C5—C6 | 116.19 (12) |
C7—N2—C1i | 111.00 (11) | N1—C5—H5A | 108.2 |
C6—N2—C1i | 109.81 (11) | C6—C5—H5A | 108.2 |
C7—N2—H2 | 107.9 | N1—C5—H5AB | 108.2 |
C6—N2—H2 | 107.9 | C6—C5—H5AB | 108.2 |
C1i—N2—H2 | 107.9 | H5A—C5—H5AB | 107.4 |
N2i—C1—C2 | 113.55 (12) | N2—C6—C5 | 115.16 (12) |
N2i—C1—H1A | 108.9 | N2—C6—H6A | 108.5 |
C2—C1—H1A | 108.9 | C5—C6—H6A | 108.5 |
N2i—C1—H1AB | 108.9 | N2—C6—H6AB | 108.5 |
C2—C1—H1AB | 108.9 | C5—C6—H6AB | 108.5 |
H1A—C1—H1AB | 107.7 | H6A—C6—H6AB | 107.5 |
C1—C2—C3 | 116.36 (12) | N2—C7—H7A | 109.5 |
C1—C2—H2A | 108.2 | N2—C7—H7B | 109.5 |
C3—C2—H2A | 108.2 | H7A—C7—H7B | 109.5 |
C1—C2—H2AB | 108.2 | N2—C7—H7C | 109.5 |
C3—C2—H2AB | 108.2 | H7A—C7—H7C | 109.5 |
H2A—C2—H2AB | 107.4 | H7B—C7—H7C | 109.5 |
N1—C3—C2 | 114.13 (12) | O2—Cl1—O1 | 110.75 (13) |
N1—C3—H3A | 108.7 | O2—Cl1—O4 | 110.14 (15) |
C2—C3—H3A | 108.7 | O1—Cl1—O4 | 106.85 (14) |
N1—C3—H3AB | 108.7 | O2—Cl1—O3 | 110.94 (12) |
C2—C3—H3AB | 108.7 | O1—Cl1—O3 | 108.56 (12) |
H3A—C3—H3AB | 107.6 | O4—Cl1—O3 | 109.50 (14) |
N2i—C1—C2—C3 | −69.05 (16) | C3—N1—C5—C6 | −61.62 (16) |
C4—N1—C3—C2 | −66.31 (16) | C7—N2—C6—C5 | −69.95 (16) |
C5—N1—C3—C2 | 171.33 (11) | C1i—N2—C6—C5 | 166.15 (12) |
C1—C2—C3—N1 | −62.42 (16) | N1—C5—C6—N2 | −77.80 (16) |
C4—N1—C5—C6 | 174.11 (13) |
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 | 2.13 | 3.0701 (14) | 159 |
N2—H2···Cl2 | 0.99 | 2.17 | 3.1038 (15) | 156 |
C1—H1A···Cl2 | 0.98 | 2.77 | 3.6868 (17) | 157 |
C5—H5AB···O3 | 0.98 | 2.39 | 3.351 (3) | 167 |
C3—H3A···Cl2i | 0.98 | 2.67 | 3.6274 (17) | 164 |
C3—H3AB···O2ii | 0.98 | 2.52 | 3.288 (3) | 135 |
C4—H4A···O4iii | 0.97 | 2.49 | 3.429 (3) | 164 |
C4—H4C···O2ii | 0.97 | 2.39 | 3.171 (3) | 137 |
C5—H5A···O3iii | 0.98 | 2.34 | 3.317 (3) | 173 |
C6—H6AB···O4iv | 0.98 | 2.31 | 3.231 (3) | 156 |
C6—H6A···Cl2i | 0.98 | 2.80 | 3.7414 (17) | 161 |
C7—H7B···O3iii | 0.97 | 2.40 | 3.333 (3) | 161 |
Symmetry codes: (i) −x+1, −y+1, −z; (ii) −x+1, −y, −z+1; (iii) −x+1, −y+1, −z+1; (iv) −x, −y+1, −z+1. |
Acknowledgements
This work was supported by a Research Grant of 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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