research communications
Investigation of nitro–nitrito trans-chloridonitro(1,4,8,11-tetraazacyclotetradecane-κ4N,N′,N′′,N′′′)cobalt(III) chloride
ofaResearch and Education Center for Natural Sciences, Keio University, 4-1-1 Hiyoshi, Kohoku-ku, Yokohama 223-8521, Japan, bDepartment of Chemistry, Chiba Institute of Technology, Shibazono 2-1-1, Narashino, Chiba 275-0023, Japan, and cDepartment of Chemistry, Faculty of Science and Technology, Keio University, Hiyoshi 3-14-1, Kohoku-ku, Yokohama 223-8522, Japan
*Correspondence e-mail: ohba@a3.keio.jp
The reaction cavity of the nitro group in the crystal of the title compound, [CoCl(NO2)(C10H24N4)]Cl, (I), was investigated to confirm that it offers sufficient free space for linkage isomerization to occur in accordance with the observed photochemical reactivity. The complex cation has crystallographic 2/m symmetry and the nitro and chloro ligands at the trans positions are statistically disordered. The complete cyclam ligand is generated by symmetry from a quarter of the molecule. In the crystal of (I), the complex cations and Cl− ions are linked into a three-dimensional network by N—H⋯Cl(counter-ion) hydrogen bonds.
CCDC reference: 1881114
1. Chemical context
The photochemical reactions of metal complexes in the solid state attract much attention from crystallographers and chemists (Coppens et al., 2002; Vittal & Quah, 2017). The present authors have investigated photochemical linkage isomerization of a series of the nitrocobalt(III) complexes, trans-[Co(en)2(NO2)(NCS)]Cl·H2O and other salts, (Ohba, Tsuchimoto & Kurachi, 2018), trans-[Co(acac)2(NO2)(pyridine derivative)] (Ohba, Tsuchimoto & Miyazaki, 2018), and trans-[Co(salen)(NO2)(pyridine derivative)] (Ohba, Tsuchimoto & Yamada, 2018). In the present study, we describe our investigations of another type of nitrocobalt complex, trans-[Co(cyclam)(NO2)Cl]Cl, (I), where cyclam stands for 1,4,8,11-tetraazacyclotetradecane. It is known that the stability of the nitrito–CoIII complexes greatly depends on the electronic effects of the co-existing ligands, and cyclam is expected to bring a small of the nitrito-to-nitro thermal reaction (Miyoshi et al., 1983). The of trans-[Co(cyclam)(NO2)2]ClO4, (II), has already been reported by Ohba et al. (2001). For (II) and the related PF6 salt, thermal conversion steps from the dinitrito to dinitro form were investigated by and DFT calculations (Eslami et al., 2014).
When a KBr disk of (I) was irradiated for 30 min with a Xe lamp, the IR spectrum showed an apparent change involving an increase in intensity of the absorption peak of ca 1000 cm−1 (see the Figure in the supporting information), which corresponds to the symmetric N—O stretching mode of the nitrito form (Eslami et al., 2014). The IR spectrum of the irradiated complex was almost unchanged on standing at room temperature for 2 h, indicating the long life-time of the nitrito form as in (II), and reverted to that before irradiation by heating at 55°C for 45 min. The of (I) was determined to establish the dimensions of the reaction cavity and steric circumstance of the nitro group, and to compare them with those in (II).
2. Structural commentary
The molecular structure of (I) is shown in Fig. 1. The coordination geometry around the Co atom is a distorted octahedron with the N5 (nitro) and Cl2 atoms at the trans positions. The macrocyclic ligand cyclam adopts the trans-III conformation of Tobe's classification (Bosnich et al., 1965). The metal atom lies at 2/m, and the atoms N5, Cl2 and C9 (the central C atom in the six-membered chelate ring) also lie on the mirror plane. There is a twofold axis running through the Co1 atom and midpoint of the C7—C7iii bond in the five-membered chelate ring of cyclam, indicating that the positions of the Cl2 and nitro N5 atoms are exchanged. Similar orientational disorder of the chloridonitrocobalt complexes is observed for trans-[Co(en)2Cl(NO2)]ClO4 (Ohba & Eishima, 2000a) and the NO3 salt (Ohba & Eishima, 2000b).
The Co—N(nitro) bond length is 1.9601 (10) Å, which is the result of restraint in the et al., 2001). On the other hand, the Co—Cl bond distance is 2.2513 (12) Å, which is similar to that observed in trans-[Co(cyclam)Cl2]Cl, 2.2533 (4) Å (Ivaniková et al., 2006). There are intramolecular C—H⋯O/Cl hydrogen bonds (Table 1).
of disorder, the length being similar to those in (II), 1.962 (5) and 1.968 (5) Å (Ohba,3. Supramolecular features
The is shown in Fig. 2. The complex cations and chloride ions are connected by N—H⋯Cl(counter-ion) hydrogen bonds, forming a three-dimensional network. In (II), there are two independent nitro ligands at the trans positions, and the O atoms of each nitro group show two possible positions (occupation factors 65 and 35%; Ohba, et al., 2001). In the following discussion, the minor O(nitro) atoms will be neglected in (II). Slices of the reaction cavities around the NO2− group near its plane in (I) and (II) are compared in Fig. 3, where the radii of neighboring atoms are assumed to be 1.0 Å greater than the corresponding van der Waals radii (Bondi, 1964), except for Co, its radius being set to 1.90 Å. The shape of the cavity in the nitro plane is mainly defined by the N/C—H⋯O(nitro) contacts which are shown in Figs. 4 and 5. Since the radius of the neighboring H atoms is assumed to be 2.20 Å, the cavity around the nitro O atoms is narrow in the intra- and intermolecular hydrogen-bond directions. In (I), the cavity has sufficient free space to both side of the nitro O atoms for rotation to become the nitrito form, as suggested by the observed photoreactivity. In (II), the cavities of the nitro groups have space at one of the O atoms for conversion to the mono- and di-nitrito forms. The bifurcated N—H⋯O,O hydrogen bonds form an R22(4) ring (Fig. 5), which is also observed in the salts of trans-[Co(en)2(NO2)(NCS)]+ complexes (Ohba, Tsuchimoto & Kurachi, 2018)
of (I)4. Database survey
There is no entry for a (cyclam)nitrocobalt(III) complex in the Cambridge Structural Database (CSD Version 5.39; Groom et al., 2016), except for trans-[Co(cyclam)(NO2)2]ClO4 (Ohba et al., 2001). The nitrito coordination was reported for certain CoIII complexes with cyclam derivatives, for example trans-[Co(Me8[14]ane)(ONO)2]ClO4 (Horn et al., 2001), where Me8[14]ane stands for 3,10-C-meso-3,5,7,7,10,12,14,14-octamethyl-1,4,8,11-tetraazacyclotetradecane, and trans-[Co(L)(NO2)(ONO)]ClO4 and cis-[Co(L)(NO2)(ONO)]ClO4 (Boyd et al., 2007), where L stands for 1-(anthracen-9-ylmethyl)-1,4,8,11-tetraazacyclotetradecane.
The structures of trans-dichloro complexes have been published for several salts, i.e. trans-[Co(cyclam)Cl2](Cl−)1.47(H3O+)0.47(H2O)3.53 (Sosa-Torres et al., 1997), trans-[Co(cyclam)Cl2]Cl (Ivaniková et al., 2006), trans-[Co(cyclam)Cl2]PF6 and trans-[Co(cyclam)Cl2]Tf2N, where Tf2N− is bis(trifluoromethanesulfonyl)amide anion (Oba & Mochida, 2015), the conformation of cyclam in these crystals being trans-III according to Tobe's classification (Bosnich et al., 1965). The (cyclam)chlorocobalt(III) alkynyl complexes such as trans-[Co(cyclam)Cl(1-ethynylnaphthalene)]CF3SO3·OEt2 (Judkins et al., 2018) have been studied for their structural and spectroscopic properties.
5. Synthesis and crystallization
trans-[Co(cyclam)Cl2]Cl was prepared by a literature method (Nakahara & Shibata, 1977) from cobalt(II) chloride hexahydrate and cyclam, and converted to trans-[Co(cyclam)Cl(NH3)]Cl2·H2O according to the method of Lee & Poon (1973). Then, trans-[Co(cyclam)Cl(NH3)]Cl2·H2O (1.0 mmol) was dissolved in 11 ml of 1% NH3 aqueous solution and neutralized with diluted HCl. To the solution sodium nitrite (8.0 mmol) and 1 ml of 1 M HCl were added, and the reaction mixture was stirred for 3 h at room temperature, and concentrated to precipitate the title compound, (I). Orange-red plate-like crystals of (I) were grown from a dimethyl sulfoxide solution by diffusion of diethyl ether vapour.
6. Refinement
Crystal data, data collection and structure . The electron densities of the nitro N5 and Cl2 atoms overlap with each other because of the orientational disorder of the complex cation. An EADP command was used for atoms N5 and Cl2, and the Co1—N5 bond distance was restrained to be 1.960 Å (s.u. = 0.001 Å) to obtain a reasonable geometry for the nitro group. The H atoms bound to C and N were positioned geometrically. They were refined as riding, with C—H/N—H = 0.97–0.98 Å, and Uiso(H) = 1.2Ueq(C/N). One reflection showing poor agreement was omitted from the final refinement.
details are summarized in Table 2Supporting information
CCDC reference: 1881114
https://doi.org/10.1107/S205698901801678X/hb7787sup1.cif
contains datablocks I, general. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S205698901801678X/hb7787Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S205698901801678X/hb7787Isup4.cdx
The IR spectra of chloro (I) and dinitro (II) complexes before and after photoirradiation for 30 min with a 150 W Xe lamp to the KBr disk, and after further standing for 2h. DOI: https://doi.org/10.1107/S205698901801678X/hb7787sup3.tif
Data collection: APEX3 (Bruker, 2016); cell
SAINT (Bruker, 2016); data reduction: SAINT (Bruker, 2016); program(s) used to solve structure: SHELXT (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015b); molecular graphics: Mercury (Macrae et al., 2008) and CAVITY (Ohashi et al., 1981); software used to prepare material for publication: SHELXL2014 (Sheldrick, 2015b) and publCIF (Westrip, 2010).[CoCl(NO2)(C10H24N4)]Cl | Dx = 1.613 Mg m−3 |
Mr = 376.17 | Mo Kα radiation, λ = 0.71073 Å |
Tetragonal, P42/m | Cell parameters from 6699 reflections |
a = 7.6052 (3) Å | θ = 2.7–27.9° |
c = 13.3873 (7) Å | µ = 1.46 mm−1 |
V = 774.31 (7) Å3 | T = 301 K |
Z = 2 | Plate, orange |
F(000) = 392 | 0.25 × 0.25 × 0.10 mm |
Bruker D8 VENTURE diffractometer | 922 reflections with I > 2σ(I) |
φ and ω scans | Rint = 0.028 |
Absorption correction: integration (SADABS; Bruker, 2016) | θmax = 27.9°, θmin = 2.7° |
Tmin = 0.704, Tmax = 0.876 | h = −9→10 |
7967 measured reflections | k = −10→9 |
953 independent reflections | l = −15→17 |
Refinement on F2 | Hydrogen site location: inferred from neighbouring sites |
Least-squares matrix: full | H-atom parameters constrained |
R[F2 > 2σ(F2)] = 0.033 | w = 1/[σ2(Fo2) + (0.0224P)2 + 0.627P] where P = (Fo2 + 2Fc2)/3 |
wR(F2) = 0.079 | (Δ/σ)max < 0.001 |
S = 1.19 | Δρmax = 0.44 e Å−3 |
953 reflections | Δρmin = −0.26 e Å−3 |
58 parameters | Extinction correction: SHELXL2014 (Sheldrick, 2015b), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
1 restraint | Extinction coefficient: 0.056 (7) |
Primary atom site location: structure-invariant direct methods |
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 | Occ. (<1) | |
Co1 | 0.5000 | 0.0000 | 0.5000 | 0.02498 (19) | |
Cl2 | 0.7410 (3) | 0.1720 (4) | 0.5000 | 0.0336 (3) | 0.5 |
Cl3 | 0.5000 | 0.5000 | 0.7500 | 0.0529 (3) | |
O4 | 0.2278 (5) | −0.2075 (6) | 0.5775 (3) | 0.0664 (11) | 0.5 |
N5 | 0.2929 (11) | −0.1534 (15) | 0.5000 | 0.0336 (3) | 0.5 |
N6 | 0.4033 (2) | 0.1478 (2) | 0.60785 (13) | 0.0352 (4) | |
H6 | 0.4853 | 0.2464 | 0.6151 | 0.042* | |
C7 | 0.4146 (4) | 0.0476 (3) | 0.70245 (16) | 0.0519 (6) | |
H7A | 0.3180 | −0.0353 | 0.7071 | 0.062* | |
H7B | 0.4085 | 0.1269 | 0.7591 | 0.062* | |
C8 | 0.2278 (3) | 0.2279 (3) | 0.5944 (2) | 0.0535 (6) | |
H8A | 0.2023 | 0.3034 | 0.6510 | 0.064* | |
H8B | 0.1396 | 0.1358 | 0.5927 | 0.064* | |
C9 | 0.2167 (5) | 0.3338 (5) | 0.5000 | 0.0618 (11) | |
H9A | 0.3113 | 0.4194 | 0.5000 | 0.074* | |
H9B | 0.1066 | 0.3981 | 0.5000 | 0.074* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Co1 | 0.0221 (3) | 0.0253 (3) | 0.0275 (3) | 0.00039 (16) | 0.000 | 0.000 |
Cl2 | 0.0237 (10) | 0.0297 (8) | 0.0476 (6) | −0.0111 (5) | 0.000 | 0.000 |
Cl3 | 0.0454 (4) | 0.0454 (4) | 0.0678 (8) | 0.000 | 0.000 | 0.000 |
O4 | 0.054 (2) | 0.075 (3) | 0.071 (2) | −0.0275 (19) | 0.0046 (19) | 0.004 (2) |
N5 | 0.0237 (10) | 0.0297 (8) | 0.0476 (6) | −0.0111 (5) | 0.000 | 0.000 |
N6 | 0.0349 (8) | 0.0325 (8) | 0.0383 (9) | −0.0020 (6) | 0.0069 (7) | −0.0065 (7) |
C7 | 0.0729 (17) | 0.0515 (14) | 0.0313 (10) | −0.0072 (11) | 0.0128 (10) | −0.0039 (9) |
C8 | 0.0368 (11) | 0.0490 (13) | 0.0746 (17) | 0.0073 (9) | 0.0170 (11) | −0.0152 (12) |
C9 | 0.0433 (19) | 0.0421 (18) | 0.100 (3) | 0.0182 (15) | 0.000 | 0.000 |
Co1—N5i | 1.9601 (10) | N6—C7 | 1.481 (3) |
Co1—N5 | 1.9601 (10) | N6—H6 | 0.9800 |
Co1—N6 | 1.9720 (16) | C7—C7iii | 1.486 (6) |
Co1—N6i | 1.9720 (16) | C7—H7A | 0.9700 |
Co1—N6ii | 1.9720 (16) | C7—H7B | 0.9700 |
Co1—N6iii | 1.9720 (16) | C8—C9 | 1.501 (4) |
Co1—Cl2 | 2.2513 (12) | C8—H8A | 0.9700 |
Co1—Cl2i | 2.2513 (12) | C8—H8B | 0.9700 |
O4—N5 | 1.221 (4) | C9—C8ii | 1.501 (4) |
N5—O4ii | 1.221 (4) | C9—H9A | 0.9700 |
N6—C8 | 1.478 (3) | C9—H9B | 0.9700 |
N5i—Co1—N5 | 180.0 | O4ii—N5—Co1 | 121.76 (19) |
N5i—Co1—N6 | 87.7 (3) | O4—N5—Co1 | 121.76 (19) |
N5—Co1—N6 | 92.3 (3) | C8—N6—C7 | 111.64 (19) |
N5i—Co1—N6i | 92.3 (3) | C8—N6—Co1 | 118.86 (15) |
N5—Co1—N6i | 87.7 (3) | C7—N6—Co1 | 108.13 (13) |
N6—Co1—N6i | 180.0 | C8—N6—H6 | 105.8 |
N5i—Co1—N6ii | 87.7 (3) | C7—N6—H6 | 105.8 |
N5—Co1—N6ii | 92.3 (3) | Co1—N6—H6 | 105.8 |
N6—Co1—N6ii | 94.14 (10) | N6—C7—C7iii | 107.55 (16) |
N6i—Co1—N6ii | 85.86 (10) | N6—C7—H7A | 110.2 |
N5i—Co1—N6iii | 92.3 (3) | C7iii—C7—H7A | 110.2 |
N5—Co1—N6iii | 87.7 (3) | N6—C7—H7B | 110.2 |
N6—Co1—N6iii | 85.86 (10) | C7iii—C7—H7B | 110.2 |
N6i—Co1—N6iii | 94.14 (10) | H7A—C7—H7B | 108.5 |
N6ii—Co1—N6iii | 180.0 | N6—C8—C9 | 112.0 (2) |
N5—Co1—Cl2 | 179.0 (5) | N6—C8—H8A | 109.2 |
N6—Co1—Cl2 | 88.42 (7) | C9—C8—H8A | 109.2 |
N6i—Co1—Cl2 | 91.58 (7) | N6—C8—H8B | 109.2 |
N6ii—Co1—Cl2 | 88.42 (7) | C9—C8—H8B | 109.2 |
N6iii—Co1—Cl2 | 91.58 (7) | H8A—C8—H8B | 107.9 |
N5i—Co1—Cl2i | 179.0 (5) | C8—C9—C8ii | 114.7 (3) |
N6—Co1—Cl2i | 91.58 (7) | C8—C9—H9A | 108.6 |
N6i—Co1—Cl2i | 88.42 (7) | C8ii—C9—H9A | 108.6 |
N6ii—Co1—Cl2i | 91.58 (7) | C8—C9—H9B | 108.6 |
N6iii—Co1—Cl2i | 88.42 (7) | C8ii—C9—H9B | 108.6 |
O4ii—N5—O4 | 116.4 (4) | H9A—C9—H9B | 107.6 |
C8—N6—C7—C7iii | 172.3 (2) | Co1—N6—C8—C9 | −54.6 (3) |
Co1—N6—C7—C7iii | 39.7 (3) | N6—C8—C9—C8ii | 67.3 (4) |
C7—N6—C8—C9 | 178.5 (2) |
Symmetry codes: (i) −x+1, −y, −z+1; (ii) x, y, −z+1; (iii) −x+1, −y, z. |
D—H···A | D—H | H···A | D···A | D—H···A |
N6—H6···Cl3 | 0.98 | 2.64 | 3.3671 (16) | 131 |
C7—H7A···O4 | 0.97 | 2.28 | 2.929 (5) | 124 |
C8—H8B···Cl2i | 0.97 | 2.80 | 3.302 (4) | 113 |
Symmetry code: (i) −x+1, −y, −z+1. |
Acknowledgements
The authors thank Dr Takashi Nemoto, Kyoto University, for making the program CAVITY available to the public.
References
Bondi, A. (1964). J. Phys. Chem. 68, 441–451. CrossRef CAS Web of Science Google Scholar
Bosnich, B., Poon, C. K. & Tobe, M. L. (1965). Inorg. Chem. 4, 1106–1109. Google Scholar
Boyd, S., McFadyen, W. D., Abrahams, B. F., Grannas, M. J. & Ghiggino, K. P. (2007). Polyhedron, 26, 1669–1676. CrossRef Google Scholar
Bruker (2016). APEX3, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Coppens, P., Novozhilova, I. & Kovalevsky, A. (2002). Chem. Rev. 102, 861–883. Web of Science CrossRef PubMed CAS Google Scholar
Eslami, A., Hasani, N. & Yeganegi, S. (2014). Eur. J. Inorg. Chem. pp. 4788–4802. CrossRef Google Scholar
Groom, C. R., Bruno, I. J., Lightfoot, M. P. & Ward, S. C. (2016). Acta Cryst. B72, 171–179. Web of Science CrossRef IUCr Journals Google Scholar
Horn, E., Roy, T. G., Hazari, S. K. S., Dey, B. K., Dey, L. & Tiekink, E. R. T. (2001). Z. Kristallogr. New. Cryst. Struct. 216, 71–72. Google Scholar
Ivaniková, R., Svoboda, I., Fuess, H. & Mašlejová, A. (2006). Acta Cryst. E62, m1553–m1554. Web of Science CrossRef IUCr Journals Google Scholar
Judkins, E. C., Zeller, M. & Ren, T. (2018). Inorg. Chem. 57, 2249–2259. CrossRef Google Scholar
Lee, W. K. & Poon, C. K. (1973). Inorg. Chem. 12, 2016–2019. CrossRef Google Scholar
Macrae, C. F., Bruno, I. J., Chisholm, J. A., Edgington, P. R., McCabe, P., Pidcock, E., Rodriguez-Monge, L., Taylor, R., van de Streek, J. & Wood, P. A. (2008). J. Appl. Cryst. 41, 466–470. Web of Science CrossRef CAS IUCr Journals Google Scholar
Miyoshi, K., Katoda, N. & Yoneda, H. (1983). Inorg. Chem. 22, 1839–1843. CrossRef CAS Web of Science Google Scholar
Nakahara, K. & Shibata, M. (1977). Editors. Sin-Jikken-Kagaku-Kouza [New Experimental Chemistry Course] 8, Syntheses of Inorganic Compounds III, pp. 1458–1459. The Chemical Society of Japan, Tokyo: Maruzen. Google Scholar
Oba, Y. & Mochida, T. (2015). Polyhedron, 99, 275–279. CrossRef Google Scholar
Ohashi, Y., Yanagi, K., Kurihara, T., Sasada, Y. & Ohgo, Y. (1981). J. Am. Chem. Soc. 103, 5805–5812. CrossRef CAS Web of Science Google Scholar
Ohba, S. & Eishima, M. (2000a). Acta Cryst. C56, e557–e558. CrossRef IUCr Journals Google Scholar
Ohba, S. & Eishima, M. (2000b). Acta Cryst. C56, e559–e560. CrossRef IUCr Journals Google Scholar
Ohba, S., Tsuchimoto, M. & Kurachi, S. (2018). Acta Cryst. E74, 1526–1531. Web of Science CrossRef IUCr Journals Google Scholar
Ohba, S., Tsuchimoto, M. & Miyazaki, H. (2018). Acta Cryst. E74, 1637–1642. CrossRef IUCr Journals Google Scholar
Ohba, S., Tsuchimoto, M. & Yamada, N. (2018). Acta Cryst. E74, 1759–1763. CrossRef IUCr Journals Google Scholar
Ohba, S., Yamada, N. & Eishima, M. (2001). Acta Cryst. E57, m12–m13. CrossRef IUCr Journals Google Scholar
Sheldrick, G. M. (2015a). Acta Cryst. A71, 3–8. Web of Science CrossRef IUCr Journals Google Scholar
Sheldrick, G. M. (2015b). Acta Cryst. C71, 3–8. Web of Science CrossRef IUCr Journals Google Scholar
Sosa-Torres, M. E. & Toscano, R. A. (1997). Acta Cryst. C53, 1585–1588. CrossRef CAS Web of Science IUCr Journals Google Scholar
Vittal, J. J. & Quah, H. S. (2017). Dalton Trans. 46, 7120–7140. CrossRef Google Scholar
Westrip, S. P. (2010). J. Appl. Cryst. 43, 920–925. Web of Science CrossRef CAS IUCr Journals Google Scholar
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