research communications
of bis{(3,5-dimethylpyrazol-1-yl)dihydro[3-(pyridin-2-yl)pyrazol-1-yl]borato}iron(II)
aInstitut für Anorganische Chemie, Christian-Albrechts-Universität Kiel, Max-Eyth-Str. 2, D-24118 Kiel, Germany
*Correspondence e-mail: sossinger@ac.uni-kiel.de
The 13H15BN5)2] was undertaken as part of a project on the modification of the recently published spin-crossover (SCO) complex [Fe{H2B(pz)(pypz)}2] (pz = pyrazole, pypz = pyridylpyrazole). To this end, a new ligand was synthesized in which two additional methyl groups are present. Its reaction with iron trifluoromethanesulfonate led to a pure sample of the title compound, as proven by X-ray powder diffraction. The consists of one complex molecule in a general position. The FeII atom is coordinated by two tridentate N-binding {H2B(3,5-(CH3)2-pz)(pypz)}− ligands. The Fe—N bond lengths range between 2.1222 (13) and 2.3255 (15) Å, compatible with FeII in the high-spin state, which was also confirmed by magnetic measurements. Other than a very weak C—H⋯N non-classical hydrogen bond linking individual molecules into rows extending parallel to [010], there are no remarkable intermolecular interactions.
of [Fe(CKeywords: crystal structure; dihydro(pyrazole)(pyridlypyrazole)borate derivative; FeII; discrete complex..
CCDC reference: 2014411
1. Chemical context
Spin-crossover (SCO) complexes of transition-metal cations (3d4–3d7) are a fascinating class of functional materials with potential for applications in electronic data storage or in spintronics (Gütlich et al., 2013; Halcrow, 2013). The transition between the diamagnetic low-spin state (S = 0 for FeII) and the paramagnetic high-spin state (S = 2 for FeII) of such complexes can be induced via temperature or light as stimuli. In most cases, SCO complexes are based on octahedral [FeIIN6] coordination spheres with chelating or mono-coordinating nitrogen donor ligands, because these combinations lead to the largest metal–ligand bond length differences between the two spin states and the largest lifetimes of the photoexcited spin states (Halcrow, 2007). Whereas hundreds of FeII SCO complexes have been reported (Halcrow, 2007), only a few of them are based on organoborate ligands such as [Fe(H2B(pz)2)2(L)] (pz = pyrazole; L = di-imine co-ligand) or tripodal organoborate ligands such as [Fe(HB(pz)3] (pz = pyrazole and derivatives thereof). These compounds are of special interest because most of them, as we and other research groups have shown, are suitable for physical vapour deposition, which is one important requirement for a possible application of these materials (Ruben & Kumar, 2019; Naggert et al., 2015; Ossinger et al., 2020a). Notably, bidentate compounds of the type [Fe(H2B(pz)2)2(L)] have been found to dissociate into the tetrahedral complex [Fe(H2B(pz)2)2] and the free co-ligand (Gopakumar et al., 2013) in the first (sub)monolayer on Au(111), whereas the SCO complex [Fe(HB(3,5-(CH3)2-pz)3)2] supported by a tridentate tris(pyrazolyl)borate ligand can be adsorbed without fragmentation on an Au(111) surface in a submonolayer (Bairagi et al., 2016, 2018). Along these lines, we synthesized and characterized the first neutral and vacuum-evaporable SCO complex based on a linear tridentate organoborate ligand. The new complex [Fe{H2B(pz)(pypz)}2] was found to crystallize in two polymorphs, I (T1/2 = ∼270 K) and II (T1/2 = ∼390 K), with form II exhibiting π–π interactions that are absent in form I (Ossinger et al., 2020c). To investigate a possible correlation between the spin-transition temperature (T1/2) and the presence of π–π interactions in more detail, we decided to modify the complex [Fe{H2B(pz)(pypz)}2] by replacing 1H-pyrazole with 3,5-dimethyl-pyrazole in the tridentate ligand. This led to the title complex, [Fe{H2B(3,5-(CH3)2-pz)(pypz)}2], which was characterized by single crystal X-ray diffraction. The corresponding X-ray powder diffraction pattern revealed that the employed synthetic route yields a pure complex (see Fig. 1 in the supporting information). It was found to be suitable for physical vapour deposition, in analogy to the parent system [Fe{H2B(pz)(pypz)}2] (Ossinger et al., 2020c). Comparison of the infrared spectra from the bulk and the vacuum-deposited compound shows identical vibrational modes, indicating that no decomposition takes place upon vacuum evaporation and deposition (Fig. S2). Magnetic measurements revealed the presence of the high-spin state in the temperature range from 25 K to 300 K (Fig. S3), in contrast to the parent system and its two polymorphs, which exhibit the low-spin in polymorph II and SCO behaviour in polymorph I. Moreover, the of the title compound is devoid of π–π interactions, similar to polymorph I of the parent complex [Fe{H2B(pz)(pypz)}2]. As the latter shows thermally induced spin crossover, this indicates that the introduction of methyl groups has shifted the magnetic properties of the parent complex into the high-spin regime.
2. Structural commentary
The II atom is coordinated by six N atoms of two tridentate mono-anionic {H2B(3,5-(CH3)2-pz)(pypz)} ligands in a slightly distorted octahedral environment (Fig. 1), as shown by different bond lengths and angles deviating from ideal values (Table 1). The Fe—N bond lengths involving the N(pz) atoms are 2.1222 (13), 2.1264 (13), 2.1782 (14) and 2.1866 (14) Å and thus are significantly shorter than those to the N(py) atoms [2.2972 (14) and 2.3255 (15) Å]. The average bond length is 2.206 Å and thus in the range expected for FeII atoms in the high-spin state.
of the title compound consists of one discrete complex in a general position. The central Fe
|
To characterize the distortion in more detail, the structural parameters Σ and Θ were calculated with the aid of the program OctaDist (OctaDist, 2019). Σ is calculated from the 12 cis-N—Fe—N angles and is a general measure of the deviation from an ideal octahedron. Θ is calculated from 24 unique N—Fe—N angles measured on the projection of two triangular faces of the octahedron along their common pseudo-threefold axis and indicates more specifically its distortion from an octahedral towards a trigonal–prismatic structure. For a perfectly octahedral complex Σ = Θ = 0 is valid (Guionneau et al., 2004; Iasco et al., 2017; Halcrow, 2013).
For the title compound, the values Σ =119.92° and Θ = 337.22° were calculated, which are significantly higher than those in the polymorphic modifications I (Σ = 92.12°, Θ = 298.06°) and II (Σ = 47.43°, Θ = 149.08°) of the parent system (Ossinger et al., 2020c).
3. Supramolecular features
In polymorph II of the parent system [Fe{H2B(pz)(pypz)}2], individual complexes are pairwise linked to dimers by intermolecular π–π interactions between the pyridine rings of the ligands of neighbouring complexes (Ossinger et al., 2020c). In the of the title compound, no parallel arrangements of pyridine rings and no intermolecular π–π interactions are observed (Fig. 2), as was the case for polymorph I of [Fe{H2B(pz)(pypz)}2].
Apart from a weak C—H⋯N hydrogen bond (Table 2) that links neighbouring molecules into rows extending parallel to [010], there are no remarkable intermolecular interactions other than van der Waals forces.
4. Database survey
There are at least 21 crystal structures of iron complexes with dihydro-bis(pyrazol-1-yl)borate and different co-ligands reported in the literature, which include, for example, [Fe(H2B(pz)2)2(phen)] and [Fe(H2B(pz)2)2(2,2′-bipy)] (Real et al., 1997; Thompson et al., 2004) as the most well-known complexes. In the others, the co-ligand is exchanged by annelated bipyridyl ligands (Kulmaczewski et al., 2014), various modified diarylethene ligands (Nihei et al., 2013; Milek et al., 2013; Mörtel et al., 2017, 2020), 4,7-dimethyl-phenanthroline (Naggert et al., 2015), dimethylbipyridine derivatives substituted in the 5,5′ position (Xue et al., 2018), diaminobipyridine (Luo et al., 2016), chiral (R)/(S)-4,5-pinenepyridyl-2-pyrazine ligands (Ru et al., 2017) and further ligands with methyl substituents at the pyrazole unit or co-ligand unit, which also includes different solvates (Ossinger et al., 2019, 2020a,b). In all of these complexes, the FeII atoms are coordinated by three bidentate chelate ligands in a distorted octahedral environment, and spin-crossover behaviour is observed. Moreover, the of the synthetic intermediate ([Fe(H2B(pz)2)2(MeOH)2]) used for the preparation of the Fe–phenanthroline complex has also been published (Ossinger et al., 2016).
Furthermore, numerous crystal structures of iron complexes based on the tripodal hydrotris(pyrazol-1-yl)borate ligand with different modifications of the pyrazole unit (Oliver et al., 1980; Calogero et al., 1994; Rheingold et al., 1997; Cecchi et al., 2001; Reger et al., 2006; Ni et al., 2011; Salmon et al., 2009) and/or another fourth substituent in place of the hydrogen atom (Sohrin et al., 1995; Reger et al., 2005a,b) or triazole (Janiak, 1994) have been reported in the literature.
5. Synthesis and crystallization
All reactions were carried out in dry solvents, and the complexation was carried out under nitrogen-atmosphere using standard Schlenk techniques or in an M-Braun Labmaster 130 glovebox under argon.
3,5-Dimethylpyrazole, 2-(1H-pyrazol-3-yl)pyridine and potassium tetrahydroborate were purchased from commercial sources and were used without further purification. Iron(II) triflate, which is also commercially available, was purified by the following method: The compound was dissolved in dry methanol (a few ml for a supersaturated solution), filtered off and afterwards the solvent was removed in vacuo. Solvents were purchased from commercial sources and purified by distillation over conventional drying agents.
Synthesis of K[H2B(3,5-(CH3)2-pz)(pypz)]: Potassium tetrahydroborate (539 mg, 0.01 mol), 3,5-dimethylpyrazole (961 mg, 0.01 mol) and 2-(1H-pyrazol-3-yl)pyridine (1.45 g, 0.01 mol) were suspended in toluene (20 ml) and refluxed for 17 h. The solution was filtered whilst hot to remove any residual traces of unreacted K[BH4]. The filtrate was allowed to cool to room temperature. A few hours later a white precipitate formed, and after one additional night of crystallization the precipitate was collected by suction filtration and subsequently dissolved in a few ml of acetonitrile. The resulting cloudy solution was again filtered by suction filtration. The solvent was removed in vacuo, and a white precipitate was obtained. Yield 260 mg (859 µmol, 9% vs K[BH4]).
Elemental analysis calculated for C13H15BKN5: C 53.62, H 5.19, N 24.05%, found: C 53.63, H 4.99, N 23.75%.
HRESI–MS(+)(CH3CN): m/z (%) = [M − K + 2H]+ calculated 254.15715, found 254.15683 (100).
1H NMR (500 MHz, CD3CN): δ/ppm = 8.49 (ddd, J = 4.9 Hz, 1.8 Hz, 1.0 Hz, 1H, py-H8), 7.72 (ddd, J = 8.0 Hz, 1.5 Hz, 1.0 Hz, 1H, py-H10), 7.68 (ddd, J = 8.0 Hz, 1.5 Hz, 1.0 Hz, 1H, py-H7), 7.50 (d, J = 2.0 Hz, 1H, pz-H5), 7.14 (ddd, J = 7.2 Hz, 4.9 Hz, 1.5 Hz, 1H, py-H9), 6.56 (d, J = 2.0 Hz, 1H, pz-H4), 5.58 (s, 1H, pz-H4A), 3.49 (dd, J = 187.8 Hz, 69.1 Hz, 2H, B-H), 2.24 (d, J = 0.6 Hz, 3H, pz-Me), 2.10 [m(d), J = 0.5 Hz, 3H, pz-Me].
13C{1H} NMR (125 MHz, CD3CN): δ/ppm = 154.72 (Cq, py-C6), 151.82 (Cq, pz-C3), 150.20 (CH, py-C8), 146.79 (Cq, pz-C3A or C5A), 143.83 (Cq, pz-C3A or C5A), 137.41 (CH, py-C7), 136.31 (CH, pz-C5), 122.18 (CH, py-C9), 120.53 (CH, py-C10), 104.21 (CH, pz-C4A), 102.86 (CH, pz-C4), 13.63 (CH3, pz-Me), 13.04 (CH3, pz-Me).
11B NMR (160 MHz, CD3CN): δ/ppm = −9.32 (t, J = 98.6 Hz, 1B).
IR (ATR): ν/cm−1 = 3069, 3048, 3022, 3005 (w, ν[=C—H]), 2952, 2917, 2907, 2860, 2815 (w, ν[–CH3]), 2362, 2325 (m, νasym.[–BH2]), 2264, 2250 (m, νsym.[–BH2]), 1695 (w), 1592 (s), 1566 (m), 1533 (m), 1511 (m), 1486 (m), 1425 (s), 1378 (w), 1352 (m), 1276 (w), 1225 (m), 1180 (s), 1158 (s), 1145 (s), 1125 (s), 1086 (s), 1056 (s), 1029 (m), 994 (m), 980 (m), 955 (m), 896 (m), 849 (m), 792 (w), 780 (m), 747 (s), 721 (m), 706 (m), 688 (m), 672 (w), 653 (w), 643 (m), 506 (w), 459 (w), 400 (m).
Raman (Bulk): ν/cm−1 = 3134, 3119, 3069, 3055, 3010 (w, ν[=C—H]), 2972, 2953, 2923, 2865 (w, ν[–CH3]), 2472, 2382, 2365, 2333 (vw, νasym.[–BH2]), 2267 (vw, νsym.[–BH2]), 1594 (s), 1567 (w), 1513 (s), 1490 (w), 1442 (w), 1358 (m), 1279 (w), 1261 (w), 1237 (w), 1226 (w), 1184 (w), 1148 (w), 1129 (w), 1090 (w), 1049 (w), 1031 (w), 993 (m), 960 (m), 796 (w), 781 (w), 707 (w), 621 (w), 589 (w).
Synthesis of [Fe{H2B(3,5-(CH3)2-pz)(pypz)}2]: To a solution of Fe(OTf)2 (124 mg, 351 µmol) in methanol (1 ml) a solution of K[H2B(3,5-(CH3)2-pz)(pypz)] (203 mg, 698 µmol) in methanol (4 ml) was added dropwise, leading to the formation of a dark-yellow-coloured solution. Immediately, a dark-yellow-coloured precipitate was formed. The suspension was stirred for 15 min at room temperature, and then the precipitate was filtered off, washed with methanol (5 ml) and dried under reduced pressure (1 h). Yield: 128 mg (229 µmol, 65% vs. Fe(OTf)2).
Elemental analysis calculated for C26H30B2FeN10: C 55.76, H 5.4, N 25.01%, found: C 55.92, H 5.26, N 24.79%.
HRESI–MS(+)(CH3CN+MeOH): m/z (%) = [M + H]+ calculated 561.22632, found 561.22575 (100).
IR (ATR): ν/cm−1 = 3138, 3118, 3079, 3060 (w, ν[=C—H]), 2979, 2960, 2924, 2858 (w, ν[–CH3]), 2417, 2364, 2303 (m, νasym.[–BH2]), 2266 (w, νsym.[–BH2]), 1605 (m), 1566 (w), 1537 (m), 1488 (w), 1445 (w), 1433 (m), 1421 (m), 1376 (m), 1354 (m), 1294 (w), 1249 (w), 1196 (m), 1170 (s), 1156 (m), 1102 (m), 1094 (m), 1072 (s), 1041 (m), 1017 (w), 982 (w), 962 (w), 880 (m), 862 (w), 792 (w), 764 (s), 723 (m), 706 (w), 686 (m), 670 (w), 655 (m), 635 (m), 608 (w), 510 (w), 482 (m), 459 (m), 410 (m).
Raman (Bulk): ν/cm−1 = 3140, 3061 (w, ν[=C—H]), 2931 (m, ν[–CH3]), 2330 (vw, νasym.[–BH2]), 2274 (vw, νsym.[–BH2]), 1653 (w), 1606 (s), 1566 (m), 1527 (s), 1489 (m), 1444 (w), 1356 (s), 1007 (m), 966 (w).
UV/Vis (KBr): λmax/nm = 204, 253, 300, 392–552 (br).
Crystallization: Single crystals of the compound were obtained under a nitrogen atmosphere by resolving microcrystalline material in dry toluene that was overlayed with dry n-hexane. This mixture was stored at 278 K, and after a few weeks long orange-coloured needle-like single crystals were formed.
Experimental details: NMR spectra were recorded in deuterated solvents on a Bruker DRX500 spectrometer operating at a 1H frequency of 500 MHz, a 13C frequency of 125 MHz, and a 11B frequency of 160 MHz. They were referenced to the residual protonated solvent signal [1H: δ(CD3CN) = 1.94 ppm], the solvent signal [13C: δ(CD3CN) = 118.26 ppm], or an (11B: BF3·Et2O) (Gottlieb et al., 1997; Fulmer et al., 2010). Signals were assigned with the help of DEPT-135 and two-dimensional correlation spectra (1H,1H-COSY, 1H,13C-HSQC, and 1H,13C-HMBC). Signal multiplicities are abbreviated as s (singlet), d (doublet), t (triplet), m (multiplet), and br (broad signal). Elemental analyses were performed using a vario MICRO cube CHNS element analyser from Elementar. Samples were burned in sealed tin containers by a stream of oxygen. High-resolution ESI mass spectra were recorded on a ThermoFisher Orbitrap spectrometer. IR spectra were recorded on a Bruker Alpha-P ATR–IR Spectrometer. Signal intensities are marked as s (strong), m (medium), w (weak) and br (broad). For FT–Raman spectroscopy, a Bruker RAM II-1064 FT-Raman Module, a R510-N/R Nd:YAG-laser (1046 nm, up to 500 mW) and a D418-T/R liquid-nitrogen-cooled, highly sensitive Ge detector or a Bruker IFS 66 with a FRA 106 unit and a 35mW Nd:YAG-laser (1064 nm) were used. XRPD experiments were performed with a Stoe Transmission Powder Diffraction System (STADI P) with Cu Kα radiation (λ = 1.5406 Å) equipped with a position-sensitive detector (Mythen-K1). UV/vis spectra were recorded with a Cary 5000 spectrometer in transmission geometry. The magnetic measurement was performed at 1 T between 300 and 2 K using a physical property measurement system (PPMS) from Quantum Design. Diamagnetic corrections were applied with the use of Pascal's constants (Bain & Berry, 2008).
6. Refinement
Crystal data, data collection and structure . C-bound hydrogen atoms were positioned with idealized geometry (methyl H atoms allowed to rotate but not to tip) and were refined with Uiso(H) = 1.2Ueq(C) (1.5 for methyl H atoms) using a riding model. B-bound hydrogen atoms were located in a difference-Fourier map and were refined freely.
details are summarized in Table 3Supporting information
CCDC reference: 2014411
https://doi.org/10.1107/S2056989020009214/wm5574sup1.cif
contains datablock I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989020009214/wm5574Isup2.hkl
Figure S1. Experimental XRPD pattern of [Fe{H2B(3,5-(CH3)2-pz)(pypz)}2] measured at rt (a) as well as simulated XRPD pattern calculated from the single https://doi.org/10.1107/S2056989020009214/wm5574sup3.png
measured at 200 K (b). DOI:Figure S2. Fourier transform infrared (FT-IR) spectra of bulk material (black dashed line) and vacuum-deposited material (red line) of the title compound measured at rt. DOI: https://doi.org/10.1107/S2056989020009214/wm5574sup4.png
Figure S3. ChiT vs T curve of the title compound between 2 and 300 K. The curves resulting from cooling and heating the sample almost coincidence. DOI: https://doi.org/10.1107/S2056989020009214/wm5574sup5.png
Data collection: X-AREA (Stoe & Cie, 2008); cell
X-AREA (Stoe & Cie, 2008); data reduction: X-AREA (Stoe & Cie, 2008); program(s) used to solve structure: SHELXT (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2018/3 (Sheldrick, 2015b); molecular graphics: DIAMOND (Brandenburg, 1999); software used to prepare material for publication: publCIF (Westrip, 2010).[Fe(C13H15BN5)2] | F(000) = 1168 |
Mr = 560.07 | Dx = 1.331 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
a = 17.1798 (6) Å | Cell parameters from 16844 reflections |
b = 8.7991 (2) Å | θ = 2.2–27.0° |
c = 18.7608 (7) Å | µ = 0.57 mm−1 |
β = 99.711 (3)° | T = 200 K |
V = 2795.37 (16) Å3 | Bar, orange |
Z = 4 | 0.20 × 0.12 × 0.08 mm |
Stoe IPDS-1 diffractometer | 5067 reflections with I > 2σ(I) |
ω scans | Rint = 0.029 |
Absorption correction: numerical (X-Red and X-Shape; Stoe & Cie, 2008) | θmax = 27.0°, θmin = 2.2° |
Tmin = 0.805, Tmax = 0.960 | h = −21→20 |
16844 measured reflections | k = −11→10 |
6071 independent reflections | l = −23→23 |
Refinement on F2 | 0 restraints |
Least-squares matrix: full | Hydrogen site location: mixed |
R[F2 > 2σ(F2)] = 0.034 | H atoms treated by a mixture of independent and constrained refinement |
wR(F2) = 0.091 | w = 1/[σ2(Fo2) + (0.0488P)2 + 0.5301P] where P = (Fo2 + 2Fc2)/3 |
S = 1.04 | (Δ/σ)max = 0.001 |
6071 reflections | Δρmax = 0.24 e Å−3 |
372 parameters | Δρmin = −0.32 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 | ||
Fe1 | 0.25357 (2) | 0.66865 (3) | 0.38412 (2) | 0.03635 (8) | |
N1 | 0.24645 (8) | 0.42005 (16) | 0.41986 (8) | 0.0424 (3) | |
C1 | 0.31541 (11) | 0.34392 (19) | 0.42876 (9) | 0.0431 (4) | |
C2 | 0.32056 (14) | 0.1918 (2) | 0.44860 (11) | 0.0556 (5) | |
H2 | 0.369711 | 0.139860 | 0.454262 | 0.067* | |
C3 | 0.25320 (15) | 0.1174 (2) | 0.45993 (11) | 0.0642 (6) | |
H3 | 0.255326 | 0.013376 | 0.473603 | 0.077* | |
C4 | 0.18277 (14) | 0.1952 (2) | 0.45128 (11) | 0.0609 (5) | |
H4 | 0.135633 | 0.145907 | 0.458790 | 0.073* | |
C5 | 0.18194 (12) | 0.3461 (2) | 0.43149 (11) | 0.0522 (4) | |
H5 | 0.133329 | 0.399861 | 0.425881 | 0.063* | |
C6 | 0.38277 (10) | 0.43509 (19) | 0.41776 (9) | 0.0419 (4) | |
N2 | 0.37079 (7) | 0.58498 (16) | 0.41015 (7) | 0.0388 (3) | |
N3 | 0.43977 (8) | 0.64900 (17) | 0.40183 (8) | 0.0432 (3) | |
C7 | 0.49500 (11) | 0.5398 (2) | 0.40489 (11) | 0.0542 (5) | |
H7 | 0.548765 | 0.555785 | 0.400833 | 0.065* | |
C8 | 0.46140 (11) | 0.4016 (2) | 0.41481 (11) | 0.0538 (5) | |
H8 | 0.486204 | 0.304748 | 0.418770 | 0.065* | |
B1 | 0.44835 (11) | 0.8240 (3) | 0.40255 (12) | 0.0481 (5) | |
H1A | 0.5065 (13) | 0.849 (2) | 0.3886 (11) | 0.059 (6)* | |
H2A | 0.4405 (12) | 0.867 (2) | 0.4583 (12) | 0.057 (6)* | |
N4 | 0.38384 (8) | 0.89317 (17) | 0.34347 (8) | 0.0415 (3) | |
N5 | 0.30409 (8) | 0.87040 (16) | 0.34245 (7) | 0.0397 (3) | |
C9 | 0.26662 (10) | 0.9666 (2) | 0.29304 (10) | 0.0458 (4) | |
C10 | 0.32095 (12) | 1.0504 (2) | 0.26233 (11) | 0.0556 (5) | |
H10 | 0.309803 | 1.125859 | 0.225828 | 0.067* | |
C11 | 0.39404 (11) | 1.0018 (2) | 0.29549 (10) | 0.0498 (4) | |
C12 | 0.17874 (11) | 0.9804 (2) | 0.27768 (12) | 0.0568 (5) | |
H12A | 0.157151 | 0.907477 | 0.240004 | 0.085* | |
H12B | 0.164113 | 1.083753 | 0.261118 | 0.085* | |
H12C | 0.157288 | 0.959006 | 0.321832 | 0.085* | |
C13 | 0.47337 (13) | 1.0549 (3) | 0.28292 (14) | 0.0679 (6) | |
H13A | 0.503941 | 1.091565 | 0.328528 | 0.102* | |
H13B | 0.466683 | 1.137548 | 0.247405 | 0.102* | |
H13C | 0.501442 | 0.970313 | 0.264603 | 0.102* | |
N21 | 0.25062 (8) | 0.55241 (17) | 0.27238 (8) | 0.0427 (3) | |
C21 | 0.31204 (11) | 0.5194 (2) | 0.23987 (10) | 0.0490 (4) | |
H21 | 0.362874 | 0.554639 | 0.261370 | 0.059* | |
C22 | 0.30524 (13) | 0.4369 (2) | 0.17666 (10) | 0.0565 (5) | |
H22 | 0.350227 | 0.416218 | 0.154950 | 0.068* | |
C23 | 0.23111 (14) | 0.3848 (3) | 0.14559 (11) | 0.0604 (5) | |
H23 | 0.224711 | 0.325513 | 0.102665 | 0.072* | |
C24 | 0.16692 (12) | 0.4197 (2) | 0.17750 (10) | 0.0552 (5) | |
H24 | 0.115568 | 0.386001 | 0.156645 | 0.066* | |
C25 | 0.17838 (10) | 0.5048 (2) | 0.24059 (9) | 0.0446 (4) | |
C26 | 0.11446 (10) | 0.5525 (2) | 0.27746 (9) | 0.0453 (4) | |
N22 | 0.13333 (8) | 0.64402 (16) | 0.33500 (8) | 0.0412 (3) | |
N23 | 0.06650 (8) | 0.67339 (18) | 0.36111 (8) | 0.0454 (3) | |
C27 | 0.00588 (10) | 0.6020 (3) | 0.31960 (12) | 0.0587 (5) | |
H27 | −0.047595 | 0.605253 | 0.326591 | 0.070* | |
C28 | 0.03319 (11) | 0.5240 (3) | 0.26587 (12) | 0.0602 (5) | |
H28 | 0.003562 | 0.463864 | 0.228849 | 0.072* | |
B21 | 0.06608 (11) | 0.7902 (3) | 0.42263 (12) | 0.0480 (5) | |
H21A | 0.0796 (12) | 0.901 (2) | 0.4020 (11) | 0.053 (5)* | |
H21B | 0.0062 (12) | 0.785 (2) | 0.4387 (10) | 0.051 (5)* | |
N24 | 0.13042 (7) | 0.74699 (16) | 0.48779 (8) | 0.0406 (3) | |
N25 | 0.20937 (7) | 0.73351 (16) | 0.48249 (7) | 0.0385 (3) | |
C29 | 0.24801 (10) | 0.7151 (2) | 0.55021 (9) | 0.0433 (4) | |
C30 | 0.19569 (11) | 0.7175 (2) | 0.59869 (10) | 0.0527 (4) | |
H30 | 0.208023 | 0.707301 | 0.649760 | 0.063* | |
C31 | 0.12210 (11) | 0.7378 (2) | 0.55775 (10) | 0.0503 (4) | |
C32 | 0.33549 (11) | 0.6980 (3) | 0.56723 (11) | 0.0631 (6) | |
H32A | 0.350805 | 0.600726 | 0.548199 | 0.095* | |
H32B | 0.352579 | 0.700541 | 0.619763 | 0.095* | |
H32C | 0.360596 | 0.781333 | 0.544921 | 0.095* | |
C33 | 0.04415 (13) | 0.7534 (4) | 0.58257 (13) | 0.0757 (7) | |
H33A | 0.021738 | 0.853680 | 0.568847 | 0.114* | |
H33B | 0.051594 | 0.742262 | 0.635260 | 0.114* | |
H33C | 0.008067 | 0.674317 | 0.559854 | 0.114* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Fe1 | 0.02667 (11) | 0.03770 (13) | 0.04343 (13) | 0.00015 (9) | 0.00229 (8) | 0.00072 (9) |
N1 | 0.0431 (7) | 0.0389 (7) | 0.0438 (7) | −0.0020 (6) | 0.0036 (6) | 0.0004 (6) |
C1 | 0.0525 (9) | 0.0378 (8) | 0.0387 (8) | 0.0031 (7) | 0.0069 (7) | −0.0024 (6) |
C2 | 0.0756 (13) | 0.0385 (10) | 0.0546 (11) | 0.0088 (9) | 0.0164 (10) | 0.0008 (8) |
C3 | 0.1000 (17) | 0.0387 (10) | 0.0559 (11) | −0.0080 (11) | 0.0187 (11) | 0.0003 (8) |
C4 | 0.0751 (14) | 0.0506 (11) | 0.0568 (11) | −0.0189 (10) | 0.0104 (10) | 0.0009 (9) |
C5 | 0.0514 (10) | 0.0516 (11) | 0.0525 (10) | −0.0101 (8) | 0.0052 (8) | 0.0025 (8) |
C6 | 0.0437 (8) | 0.0409 (9) | 0.0403 (8) | 0.0105 (7) | 0.0050 (6) | 0.0008 (7) |
N2 | 0.0298 (6) | 0.0408 (7) | 0.0446 (7) | 0.0034 (5) | 0.0028 (5) | 0.0020 (6) |
N3 | 0.0285 (6) | 0.0516 (8) | 0.0485 (8) | 0.0053 (6) | 0.0034 (5) | 0.0039 (6) |
C7 | 0.0349 (8) | 0.0649 (12) | 0.0631 (11) | 0.0139 (8) | 0.0089 (8) | 0.0066 (9) |
C8 | 0.0476 (10) | 0.0521 (11) | 0.0623 (11) | 0.0191 (9) | 0.0112 (8) | 0.0038 (9) |
B1 | 0.0322 (9) | 0.0524 (11) | 0.0569 (12) | −0.0038 (8) | −0.0007 (8) | 0.0055 (9) |
N4 | 0.0324 (6) | 0.0429 (7) | 0.0487 (8) | −0.0025 (6) | 0.0056 (5) | 0.0040 (6) |
N5 | 0.0321 (6) | 0.0399 (7) | 0.0457 (7) | −0.0008 (5) | 0.0029 (5) | 0.0042 (6) |
C9 | 0.0424 (9) | 0.0439 (9) | 0.0484 (9) | 0.0041 (7) | 0.0001 (7) | 0.0061 (7) |
C10 | 0.0565 (11) | 0.0551 (11) | 0.0542 (11) | 0.0009 (9) | 0.0063 (8) | 0.0172 (9) |
C11 | 0.0480 (10) | 0.0496 (10) | 0.0531 (10) | −0.0051 (8) | 0.0119 (8) | 0.0061 (8) |
C12 | 0.0439 (10) | 0.0586 (12) | 0.0633 (11) | 0.0090 (8) | −0.0037 (8) | 0.0111 (9) |
C13 | 0.0558 (12) | 0.0706 (14) | 0.0809 (15) | −0.0096 (11) | 0.0219 (11) | 0.0160 (12) |
N21 | 0.0387 (7) | 0.0448 (8) | 0.0434 (7) | −0.0010 (6) | 0.0035 (6) | 0.0019 (6) |
C21 | 0.0448 (9) | 0.0538 (11) | 0.0487 (10) | 0.0018 (8) | 0.0084 (7) | 0.0032 (8) |
C22 | 0.0631 (12) | 0.0607 (12) | 0.0475 (10) | 0.0071 (10) | 0.0143 (9) | 0.0027 (9) |
C23 | 0.0767 (14) | 0.0591 (12) | 0.0445 (10) | 0.0002 (11) | 0.0076 (9) | −0.0054 (9) |
C24 | 0.0570 (11) | 0.0583 (12) | 0.0469 (10) | −0.0084 (9) | −0.0009 (8) | −0.0045 (8) |
C25 | 0.0430 (9) | 0.0455 (9) | 0.0429 (8) | −0.0034 (7) | 0.0005 (7) | 0.0013 (7) |
C26 | 0.0375 (8) | 0.0502 (10) | 0.0448 (9) | −0.0061 (7) | −0.0030 (7) | −0.0013 (7) |
N22 | 0.0298 (6) | 0.0448 (8) | 0.0469 (7) | −0.0006 (5) | 0.0005 (5) | −0.0006 (6) |
N23 | 0.0272 (6) | 0.0539 (9) | 0.0531 (8) | −0.0012 (6) | 0.0013 (5) | −0.0010 (7) |
C27 | 0.0305 (8) | 0.0751 (13) | 0.0670 (12) | −0.0082 (9) | −0.0016 (8) | −0.0109 (10) |
C28 | 0.0399 (9) | 0.0740 (14) | 0.0623 (12) | −0.0125 (9) | −0.0039 (8) | −0.0153 (10) |
B21 | 0.0317 (9) | 0.0549 (12) | 0.0556 (11) | 0.0055 (8) | 0.0020 (8) | −0.0017 (9) |
N24 | 0.0300 (6) | 0.0438 (8) | 0.0483 (8) | −0.0002 (6) | 0.0072 (5) | −0.0011 (6) |
N25 | 0.0297 (6) | 0.0402 (7) | 0.0449 (7) | 0.0023 (5) | 0.0042 (5) | −0.0005 (6) |
C29 | 0.0397 (8) | 0.0431 (9) | 0.0455 (9) | 0.0056 (7) | 0.0022 (7) | −0.0012 (7) |
C30 | 0.0512 (10) | 0.0627 (11) | 0.0440 (9) | 0.0047 (9) | 0.0073 (8) | 0.0016 (8) |
C31 | 0.0426 (9) | 0.0576 (11) | 0.0524 (10) | −0.0021 (8) | 0.0125 (7) | −0.0007 (8) |
C32 | 0.0428 (10) | 0.0910 (16) | 0.0515 (10) | 0.0188 (10) | −0.0031 (8) | −0.0079 (10) |
C33 | 0.0482 (11) | 0.118 (2) | 0.0653 (13) | −0.0035 (13) | 0.0219 (10) | −0.0001 (14) |
Fe1—N2 | 2.1222 (13) | C9—C12 | 1.493 (2) |
Fe1—N22 | 2.1264 (13) | C10—C11 | 1.372 (3) |
Fe1—N5 | 2.1782 (14) | C11—C13 | 1.497 (3) |
Fe1—N25 | 2.1866 (14) | N21—C21 | 1.337 (2) |
Fe1—N1 | 2.2972 (14) | N21—C25 | 1.350 (2) |
Fe1—N21 | 2.3255 (15) | C21—C22 | 1.379 (3) |
N1—C5 | 1.334 (2) | C22—C23 | 1.386 (3) |
N1—C1 | 1.347 (2) | C23—C24 | 1.375 (3) |
C1—C2 | 1.388 (2) | C24—C25 | 1.386 (3) |
C1—C6 | 1.451 (3) | C25—C26 | 1.455 (3) |
C2—C3 | 1.377 (3) | C26—N22 | 1.342 (2) |
C3—C4 | 1.376 (3) | C26—C28 | 1.399 (2) |
C4—C5 | 1.378 (3) | N22—N23 | 1.347 (2) |
C6—N2 | 1.339 (2) | N23—C27 | 1.346 (2) |
C6—C8 | 1.393 (2) | N23—B21 | 1.547 (3) |
N2—N3 | 1.3449 (19) | C27—C28 | 1.366 (3) |
N3—C7 | 1.345 (2) | B21—N24 | 1.551 (2) |
N3—B1 | 1.547 (3) | N24—C31 | 1.346 (2) |
C7—C8 | 1.372 (3) | N24—N25 | 1.3816 (18) |
B1—N4 | 1.553 (2) | N25—C29 | 1.340 (2) |
N4—C11 | 1.345 (2) | C29—C30 | 1.382 (3) |
N4—N5 | 1.3817 (18) | C29—C32 | 1.490 (2) |
N5—C9 | 1.338 (2) | C30—C31 | 1.376 (3) |
C9—C10 | 1.388 (3) | C31—C33 | 1.496 (3) |
N2—Fe1—N22 | 151.54 (6) | N5—C9—C10 | 110.18 (15) |
N2—Fe1—N5 | 86.86 (5) | N5—C9—C12 | 122.54 (17) |
N22—Fe1—N5 | 110.14 (5) | C10—C9—C12 | 127.25 (17) |
N2—Fe1—N25 | 110.34 (5) | C11—C10—C9 | 105.92 (16) |
N22—Fe1—N25 | 86.68 (5) | N4—C11—C10 | 108.20 (16) |
N5—Fe1—N25 | 107.84 (5) | N4—C11—C13 | 123.53 (17) |
N2—Fe1—N1 | 72.40 (5) | C10—C11—C13 | 128.27 (18) |
N22—Fe1—N1 | 86.20 (5) | C21—N21—C25 | 117.96 (16) |
N5—Fe1—N1 | 157.65 (5) | C21—N21—Fe1 | 127.44 (12) |
N25—Fe1—N1 | 87.65 (5) | C25—N21—Fe1 | 114.43 (12) |
N2—Fe1—N21 | 86.01 (5) | N21—C21—C22 | 123.22 (18) |
N22—Fe1—N21 | 72.10 (5) | C21—C22—C23 | 118.3 (2) |
N5—Fe1—N21 | 89.10 (5) | C24—C23—C22 | 119.36 (19) |
N25—Fe1—N21 | 156.60 (5) | C23—C24—C25 | 118.91 (18) |
N1—Fe1—N21 | 81.38 (5) | N21—C25—C24 | 122.18 (17) |
C5—N1—C1 | 118.35 (16) | N21—C25—C26 | 114.32 (15) |
C5—N1—Fe1 | 126.76 (13) | C24—C25—C26 | 123.49 (16) |
C1—N1—Fe1 | 114.89 (11) | N22—C26—C28 | 109.37 (17) |
N1—C1—C2 | 121.87 (18) | N22—C26—C25 | 117.15 (14) |
N1—C1—C6 | 114.42 (15) | C28—C26—C25 | 133.48 (17) |
C2—C1—C6 | 123.70 (17) | C26—N22—N23 | 107.61 (13) |
C3—C2—C1 | 118.8 (2) | C26—N22—Fe1 | 119.67 (11) |
C4—C3—C2 | 119.41 (19) | N23—N22—Fe1 | 130.40 (11) |
C3—C4—C5 | 118.7 (2) | C27—N23—N22 | 108.89 (15) |
N1—C5—C4 | 122.9 (2) | C27—N23—B21 | 129.91 (16) |
N2—C6—C8 | 109.69 (16) | N22—N23—B21 | 120.69 (13) |
N2—C6—C1 | 116.60 (15) | N23—C27—C28 | 109.43 (17) |
C8—C6—C1 | 133.68 (17) | C27—C28—C26 | 104.69 (16) |
C6—N2—N3 | 107.60 (13) | N23—B21—N24 | 109.44 (15) |
C6—N2—Fe1 | 119.29 (11) | C31—N24—N25 | 109.38 (13) |
N3—N2—Fe1 | 130.43 (11) | C31—N24—B21 | 127.18 (15) |
C7—N3—N2 | 108.96 (15) | N25—N24—B21 | 122.83 (14) |
C7—N3—B1 | 130.21 (16) | C29—N25—N24 | 106.11 (13) |
N2—N3—B1 | 120.03 (14) | C29—N25—Fe1 | 125.55 (11) |
N3—C7—C8 | 109.22 (16) | N24—N25—Fe1 | 124.62 (10) |
C7—C8—C6 | 104.53 (16) | N25—C29—C30 | 110.40 (15) |
N3—B1—N4 | 109.16 (15) | N25—C29—C32 | 122.39 (17) |
C11—N4—N5 | 109.56 (14) | C30—C29—C32 | 127.20 (17) |
C11—N4—B1 | 126.75 (15) | C31—C30—C29 | 105.85 (16) |
N5—N4—B1 | 122.65 (14) | N24—C31—C30 | 108.26 (16) |
C9—N5—N4 | 106.14 (13) | N24—C31—C33 | 123.06 (17) |
C9—N5—Fe1 | 126.18 (11) | C30—C31—C33 | 128.65 (18) |
N4—N5—Fe1 | 124.57 (10) |
D—H···A | D—H | H···A | D···A | D—H···A |
C3—H3···N25i | 0.95 | 2.60 | 3.502 (4) | 159 |
Symmetry code: (i) x, y−1, z. |
Fe(1)-N(2) | 2.1222 (13) | Fe(1)-N(25) | 2.1866 (14) |
Fe(1)-N(22) | 2.1264 (13) | Fe(1)-N(1) | 2.2972 (14) |
Fe(1)-N(5) | 2.1782 (14) | Fe(1)-N(21) | 2.3255 (15) |
Average bond length | 2.206 | ||
N(2)-Fe(1)-N(5) | 86.86 (5) | N(22)-Fe(1)-N(1) | 86.20 (5) |
N(22)-Fe(1)-N(5) | 110.14 (5) | N(25)-Fe(1)-N(1) | 87.65 (5) |
N(2)-Fe(1)-N(25) | 110.34 (5) | N(2)-Fe(1)-N(21) | 86.01 (5) |
N(22)-Fe(1)-N(25) | 86.68 (5) | N(22)-Fe(1)-N(21) | 72.10 (5) |
N(5)-Fe(1)-N(25) | 107.84 (5) | N(5)-Fe(1)-N(21) | 89.10 (5) |
N(2)-Fe(1)-N(1) | 72.40 (5) | N(1)-Fe(1)-N(21) | 81.38 (5) |
Acknowledgements
We thank Professor Dr Wolfgang Bensch for access to his experimental facilities.
Funding information
This project was supported by the DFG (SFB 677 Function by Switching) and the State of Schleswig-Holstein.
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