research communications
A new structural model for NiFe hydrogenases: an unsaturated analogue of a classic hydrogenase model leads to more enzyme-like Ni—Fe distance and interplanar fold
aDepartment of Chemical and Physical Sciences, University of Toronto Mississauga, 3359 Mississauga Rd, Mississauga, Ontario, L5L 1C6, Canada, and bDepartment of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario, M5S 3H6, Canada
*Correspondence e-mail: ulrich.fekl@utoronto.ca
The complex cation in the title compound, (carbonyl-1κC)(1η5-pentamethylcyclopentadienyl)(μ-2,3,9,10-tetramethyl-1,4,8,11-tetrathiaundeca-2,9-diene-1,11-diido-1κ2S,S′′′:2κ4S,S′,S′′,S′′′)ironnickel(Fe—Ni) hexafluorophosphate, [FeNi(C10H15)(C11H18S4)(CO)]PF6 or [Ni(L′)FeCp*(CO)]PF6, is composed of the nickel complex fragment [Ni(L′)] coordinated as a metalloligand (using S1 and S4) to the [FeCp*(CO)]+ fragment, where (L′)2− is [S—C(Me)=C(Me)—S—(CH2)3—S—C(Me)=C(Me)—S]2− and where Cp*− is cyclo-C5(Me)5− (pentamethylcyclopentadienyl). The ratio of hexafluorophosphate anion per complex cation is 1:1. The structure at 150 K has orthorhombic (Pbcn) symmetry. The atoms of the complex cation are located on general positions (multiplicity = 8), whereas there are two independent hexafluorophosphate anions, each located on a twofold axis (Wyckoff position 4c; multiplicity = 4). The structure of the new dimetallic cation [Ni(L′)FeCp*(CO)]+ can be described as containing a three-legged piano-stool environment for iron [Cp*Fe(CO)`S2'] and an approximately square-planar `S4' environment for Ni. The NiS2Fe diamond-shaped is notably folded at the S—S hinge: the angle between the NiS2 plane and the FeS2 plane normals is 64.85 (6)°. Largely because of this fold, the nickel–iron distance is relatively short, at 2.9195 (8) Å. The structural data for the complex cation, which contains a new unsaturated `S4' ligand (two C=C double bonds), provide an interesting comparison with the known NiFe hydrogenase models containing a saturated `S4'-ligand analogue having the same number of carbon atoms in the ligand backbone, namely with the structures of [Ni(L)FeCp(CO)]+ (as the PF6− salt, CH2Cl2 solvate) and [Ni(L)FeCp*(CO)]+ (as the PF6− salt), where (L)2− is [S—CH2—CH2—S—(CH2)3—S—CH2—CH2—S]2− and Cp− is cyclopentadienyl. The saturated analogues [Ni(L)FeCp(CO)]+ and [Ni(L)FeCp*(CO)]+ have similar Ni—Fe distances: 3.1727 (6), 3.1529 (7) Å (two independent molecules in the unit cell) and 3.111 (5) Å, respectively, for the two complexes, whereas [Ni(L′)FeCp*(CO)]+ described here stands out with a much shorter Ni—Fe distance [2.9196 (8) Å]. Also, [Ni(L)FeCp(CO)]+ and [Ni(L)FeCp*(CO)]+ show interplanar fold angles that are similar between the two: 39.56 (5), 41.99 (5) (independent molecules in the unit cell) and 47.22 (9) °, respectively, whereas [Ni(L′)FeCp*(CO)]+ possesses a much more pronounced fold [64.85 (6)°]. Given that larger fold angles and shorter Ni—Fe distances are considered to be structurally closer to the enzyme, unsaturation in an `S4'-ligand of the type (S—C2—S—C3—S—C2—S)2− seems to increase structural resemblance to the enzyme for structural models of the type [Ni(`S4')FeCpR(CO)]+ (CpR = Cp or Cp*).
Keywords: crystal structure; NiFe hydrogenase; enzyme model; bioinorganic; sulfur ligand.
CCDC reference: 1859284
1. Chemical context
Since the discovery and structural elucidation of nickel–iron hydrogenases, synthetic chemists have worked towards closer and closer structural models for the NiFe hydrogen-splitting active site (Lubitz et al., 2014). This active site contains two terminal sulfur donors and two bridging sulfur donors coordinated to nickel, as well as a pseudo-octahedal coordination sphere around iron, which is completed by cyano and carbonyl ligands (Fig. 1, left). Several closely related models of the active site have been prepared by combining an Ni(`S4') fragment (`S4' = dianionic tetradentate sulfur ligand) with an [FeCpR(CO)]+ fragment (CpR = Cp, C5H5 or Cp*, C5Me5), as illustrated in Fig. 1 (right) (Canaguier et al., 2010; Yang et al., 2015; Zhu et al., 2005). These complexes have an overall mono-cationic charge, consistent with formal NiII and FeII oxidations states. The first `S4' ligand used in this capacity featured a saturated two–three–two carbon linker, in L2− = [S—CH2—CH2—S—(CH2)3—S—CH2—CH2—S]2− (Fig. 2, left) (Yang et al., 2015; Zhu et al., 2005).
Here, we present a new [Ni(`S4')FeCpR(CO)]+ model based on an analogous but unsaturated `S4' ligand, namely L′2− = [S—C(Me)=C(Me)—S—(CH2)3—S—C(Me)=C(Me)—S]2− (Fig. 2, middle), and assess the structural consequences of incorporating the unsaturated ligand. For comparison, we will also discuss a literature [Ni(`S4')Fe(CpR)(CO)]+ complex in which the `S4' ligand has a four-carbon linker in the remote portion of the backbone (L′′2−, Fig. 2, right) (Canaguier et al., 2010).
2. Structural commentary
[Ni(L′)FeCp*(CO)]+ was obtained as solvent-free crystals containing the PF6− counter-ion. A drawing showing both cation and anion in this salt is shown below (see Supramolecular features), and the intramolecular structural features of the cation are discussed first. The structure of [Ni(L′)FeCp*(CO)]+ is shown in Fig. 3. It contains a three-legged piano stool environment for iron and an approximately square-planar `S4' environment for Ni (sum of bond angles around Ni1 = 359.83°). Selected metal–ligand distances are Ni1—S1 = 2.1616 (11), Ni1—S2 = 2.1530 (12), Ni1—S3 = 2.1507 (11), Ni1—S4 = 2.1563 (12) Å, and Fe1—S1 = 2.3309 (12), Fe1—S4 = 2.3602 (12), Fe1—C11 = 1.768 (5), Fe1—C1 = 2.080 (4), Fe1—C2 = 2.107 (4), Fe1—C3 = 2.126 (4), Fe1—C4 = 2.138 (4), Fe1—C5 = 2.098 (4) Å. The intermetallic (Ni1—Fe1) distance is relatively short, i.e. 2.9195 (8) Å. The NiS2Fe diamond is markedly folded at the S—S hinge: the angle between the NiS2 plane and the FeS2 plane normals (dihedral angle; 180° − hinge angle) is 64.85 (6)°, and this fold largely accounts for the short nickel–iron distance.
In the following discussion, we compare the structural features obtained with the unsaturated ligand L′2− with those of literature complexes using the saturated ligand L2−. The structures of [Ni(L)FeCp(CO)]+, as the PF6− salt/ CH2Cl2 solvate (Zhu et al., 2005), and [Ni(L)FeCp*(CO)]+, as the PF6− salt (Yang et al., 2015), are known. Both saturated analogues [Ni(L)FeCp(CO)]+ and [Ni(L)FeCp*(CO)]+ show Ni—Fe distances that are similar for the two, 3.1727 (6)/3.1529 (7) Å (two independent molecules in the unit cell) and 3.111 (5) Å, respectively, for the two complexes. The [Ni(L′)FeCp*(CO)]+ complex, on the other hand, has a much shorter Ni—Fe distance [2.9195 (8), see above]. Also, [Ni(L)FeCp(CO)]+ and [Ni(L)FeCp*(CO)]+ show interplanar fold angles that are similar for the two, 39.56 (5)/41.99 (5)° (two independent molecules in the unit cell) and 47.22 (9)°, respectively, while [Ni(L′)FeCp*(CO)]+ has a much larger fold angle of 64.85 (6)° (see above). The large fold angle and short Ni—Fe distance observed in the complex with the unsaturated ligand L′ match the structure of the enzymatic active site more closely than the angles/distances of the complexes containing the saturated ligand L. For eight structurally characterized enzymes, the dihedral angles range from 59 to 99° and the Ni—Fe distances range from 2.53 to 2.97 Å (one outlier being desulfovibrio fructosovorans with 46° and 3.23 Å; Zhu et al., 2005). We have thus provided evidence that unsaturation in an `S4'-ligand of the type (S—C2—S—C3—S—C2—S)2− can increase structural resemblance to the enzyme in models of the type [Ni(`S4')FeCpR(CO)]+. Structural similarity to the enzyme in models was, in alternative approaches, also favoured when additional donor atoms were incorporated into the ligand chain (such as `S3N2') or where two bidentate chelate ligands were used instead of one large `S4' ligand. (Zhu et al., 2005) Within the context of linear `S4' ligands, an [Ni(L′′)FeCp*(CO)]+ model with four carbon atoms, instead of three, in the remote portion of the backbone (see L′′2− in Fig. 2, right) provided an Ni—Fe distance and fold angle very similar to those of the L′ analogue, of 2.9611 (8) Å and 62.48 (4)°, respectively (Canaguier et al., 2010). In terms of activity, [Ni(L′′)FeCp*(CO)]+ was shown to be active as a hydrogen-production catalyst (Canaguier et al., 2010), which suggests that the [Ni(L′)Cp*(CO)]+ complex, with the unsaturated `S4' ligand L′, might warrant deeper investigation. We conclude that the introduction of unsaturation in the `S4' ligand led to a better structural model relative to the unsaturated ligand, highlighting a new variant of the classic [Ni('S4')FeCpR(CO)]+-type hydrogenase model.
3. Supramolecular features
The structure results from packing of discrete cations [Ni(L′)FeCp*(CO)]+ with hexafluorophosphate anions, without solvent molecules and without any solvent-accessible void. The ratio of hexafluorophosphate anion per complex cation is 1:1. The atoms of the complex cation are situated on general positions (multiplicity = 8), whereas there are two independent hexafluorophosphate anions, each situated on a twofold axis (Wyckoff position 4c in Pbcn; multiplicity = 4). A picture of the packing is shown in Fig. 4 (top, 30% probability ellipsoids), along with labeling of all non-H atoms in the (bottom). There are no classical hydrogen bonds but there are C—H⋯F hydrogen bonds to hexafluorophosphate (C6—H6B⋯F4 = 2.55 Å; C15—H15B⋯F3i = 2.55 Å; C21—H21C⋯F4ii = 2.48 Å; C22—H22C⋯F1iii = 2.52 Å) and a C—H⋯O short contact (C14—H14A⋯O1 = 2.41 Å) [symmetry codes: (i) −x + 2, y, −z + ; (ii) −x + 1, y, −z + ; (iii) −x + , y + , z].
4. Database survey
The Cambridge Crystallographic Database (version 5.39 including updates up to February 2018; Groom et al., 2016) was surveyed. A search was performed aimed at finding Ni1Fe1 complexes that contain at least one (possibly substituted) cyclopentadienyl unit, at least one carbonyl (CO) coordinated to iron, and a nickel center bonded to at least four sulfurs. The that was used for the search contained a cyclo-C5 unit (any type of bond allowed), a nickel atom bonded to four sulfur atoms (any type of bond allowed), as well as an Fe–C–O unit (any type of bond for Fe—C and for C—O). Out of the six hits, RULQEV, RULQOF and RULQUL are trimetallic (instead of dimetallic) complexes (and also do not contain a cyclopentadienyl but rather a saturated five-membered ring within a polycyclic structure). Since they are not very close analogues of [Ni(L′)FeCp*(CO)]+, they are not discussed further. LAZVUE (Zhu et al., 2005) contains [Ni(L)FeCp(CO)]+ (as the PF6− salt, CH2Cl2 solvate), MUDXOA (Yang et al., 2015) contains [Ni(L)FeCp*(CO)]+ (as the PF6− salt), and SUWWAJ (Canaguier et al., 2010) contains [Ni(L′′)FeCp*(CO)]+ (as the BF4− salt, CH2Cl2 solvate). These three complex cations are discussed in detail above.
5. Synthesis and crystallization
The syntheses were performed in dried solvents under an inert atmosphere (nitrogen or argon; vacuum) using standard glove-box (MBraun) and Schlenk techniques. Deuterated NMR solvents were from Cambridge Isotopes. [Cp*Fe(CO)2]2 was acquired from Alfa Aesar. All other chemicals were obtained from Sigma–Aldrich. Photolysis was performed using a 160 W mercury vapour lamp (model: Westron Mega-Ray Self-Ballasted Zoologist).
Ni(S2C2Me2)2: This precursor for the nickel part of the complex was prepared as described in the literature (Schrauzer & Mayweg, 1965).
Ni(L′): Ni(L′), i.e. Ni(S—C(Me)=C(Me)—S—(CH2)3—S—C(Me)=C(Me)—S) was prepared by alkylation of Na2[Ni(S2C2Me2)2] using 1,3-dibromopropane. Na2[Ni(S2C2Me2)] was prepared from Ni(S2C2Me2)2 by reduction with excess sodium in THF (344 K, 18h, in sealed vessel), until the colour had changed from deep purple to brown–yellow. The subsequent alkylation of [Ni(S2C2Me2)]2− using 1,3-dibromopropane was performed analogously to the procedure described by Schrauzer and co-workers for the closely related Ni(S—C(Ph)=C(Ph)—S—(CH2)3—S—C(Ph)=C(Ph)—S). (Zhang et al., 1992)
[Cp*Fe(CO)2(NCMe)][PF6]: This precursor for the iron part of the complex was prepared according to the general procedure for [Cp*Fe(CO)2(solvent)]+ given by Catheline & Astruc (1984), using MeCN (acetontrile) as the solvent.
[Ni(L′)FeCp*(CO/NCMe)][PF6]: Crude [Cp*Fe(CO)2(NCMe)][PF6] (210 mg, 0.48 mmol) was combined with 6 ml of acetonitrile and filtered through a glass filter frit. While purging with argon, the reaction was irradiated with UV–visible light (160 W, see above) for 16 h. Under an inert atmosphere, a solution of 155 mg (0.46 mmol) of Ni(L′) in ca 7 ml of dichloromethane was added. The reaction mixture was heated under active argon flow to 325 K for 2 h. After cooling to room temperature, the volatiles were slowly removed under vacuum. The solid was dried under vacuum and stored in the glove-box. Yield of crude product: 253 mg (75%). 1H NMR (200 MHz, 298 K, CD3CN) δ 1.60 [s, (CH3)5C5]; δ 1.91 (s, CH3—C—S); δ 1.96 (s, CH3—C—S); δ 2.31 (s, br, CH3CN—Fe); δ 2.0–3.7 [m, br, S—(CH2)3—S]. Note that the sample thus prepared showed a 1H NMR signal for metal-coordinated acetonitrile. The purpose of the prolonged photolysis was to remove all CO from iron, in order to selectively prepare [Ni(L′)FeCp*(NCMe)][PF6]. However, the sample obtained appeared to be a mixture of [Ni(L′)FeCp*(CO)][PF6] and [Ni(L′)FeCp*(NCMe)][PF6] and is thus referred to as [Ni(L′)FeCp*(CO/NCMe)][PF6]. Yet, crystallization from acetone yielded exclusively [Ni(L′)FeCp*(CO)][PF6], in crystalline form.
Crystallization of [Ni(L′)FeCp*(CO)][PF6]: 11 mg of [Ni(L′)FeCp*(CO/NCMe)][PF6] were dissolved in 1.5 ml of acetone and filtered through 1 cm of Celite. Through solvent vapor diffusion, by placing the loosely capped vial into a larger vessel containing diethyl ether vapour (and some liquid), crystals of [Ni(L′)FeCp*(CO)][PF6] were grown within two days at 308 K.
6. Refinement
Crystal data, data collection and structure . All H atoms were placed in calculated positions and included in the refinment in a riding-model approximation with C—H distances of 0.98 and 0.99 Å and Uiso(H) = 1.2Ueq(C) or 1.5Ueq(Cmethyl).
details are summarized in Table 1Supporting information
CCDC reference: 1859284
https://doi.org/10.1107/S2056989018010939/zl2735sup1.cif
contains datablock I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989018010939/zl2735Isup2.hkl
Data collection: COLLECT (Nonius, 1998); cell
DENZO-SMN (Otwinowski & Minor, 1997); data reduction: DENZO-SMN (Otwinowski & Minor, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2016 (Sheldrick, 2015); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).[FeNi(C10H15)(C11H18S4)(CO)]PF6 | Dx = 1.712 Mg m−3 |
Mr = 701.25 | Mo Kα radiation, λ = 0.71073 Å |
Orthorhombic, Pbcn | Cell parameters from 38285 reflections |
a = 15.4081 (3) Å | θ = 2.6–27.5° |
b = 18.3762 (3) Å | µ = 1.65 mm−1 |
c = 19.2154 (3) Å | T = 150 K |
V = 5440.69 (16) Å3 | Block, green |
Z = 8 | 0.20 × 0.18 × 0.12 mm |
F(000) = 2880 |
Nonius KappaCCD diffractometer | 6224 independent reflections |
Radiation source: fine-focus sealed tube | 3874 reflections with I > 2σ(I) |
Detector resolution: 9 pixels mm-1 | Rint = 0.079 |
φ scans and ω scans with κ offsets | θmax = 27.5°, θmin = 2.6° |
Absorption correction: multi-scan (SORTAV; Blessing, 1995) | h = −19→19 |
Tmin = 0.759, Tmax = 0.850 | k = −23→23 |
38285 measured reflections | l = −24→24 |
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) = 0.148 | w = 1/[σ2(Fo2) + (0.0765P)2 + 2.0266P] where P = (Fo2 + 2Fc2)/3 |
S = 1.07 | (Δ/σ)max = 0.002 |
6224 reflections | Δρmax = 1.12 e Å−3 |
335 parameters | Δρmin = −0.73 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 | ||
Ni1 | 0.74296 (4) | 0.67056 (3) | 0.52192 (3) | 0.02311 (16) | |
Fe1 | 0.56172 (4) | 0.71009 (3) | 0.49879 (3) | 0.02225 (17) | |
S1 | 0.68117 (7) | 0.70012 (6) | 0.42497 (5) | 0.0256 (3) | |
S2 | 0.79921 (7) | 0.57496 (6) | 0.47542 (5) | 0.0281 (3) | |
S3 | 0.79344 (7) | 0.64527 (6) | 0.62343 (5) | 0.0268 (3) | |
S4 | 0.67593 (7) | 0.76476 (6) | 0.56176 (5) | 0.0256 (3) | |
O1 | 0.5610 (2) | 0.55947 (17) | 0.54595 (17) | 0.0398 (8) | |
C1 | 0.4278 (3) | 0.7053 (2) | 0.5115 (2) | 0.0248 (9) | |
C2 | 0.4585 (3) | 0.7723 (2) | 0.5392 (2) | 0.0265 (10) | |
C3 | 0.4983 (3) | 0.8115 (2) | 0.4831 (2) | 0.0303 (10) | |
C4 | 0.4907 (3) | 0.7698 (2) | 0.4222 (2) | 0.0316 (10) | |
C5 | 0.4483 (3) | 0.7029 (2) | 0.4388 (2) | 0.0276 (10) | |
C6 | 0.3751 (3) | 0.6504 (2) | 0.5513 (2) | 0.0353 (11) | |
H6A | 0.313257 | 0.661374 | 0.545916 | 0.053* | |
H6B | 0.390791 | 0.652574 | 0.600690 | 0.053* | |
H6C | 0.387078 | 0.601560 | 0.533256 | 0.053* | |
C7 | 0.4426 (3) | 0.7979 (3) | 0.6122 (2) | 0.0357 (11) | |
H7A | 0.380057 | 0.803763 | 0.619663 | 0.054* | |
H7B | 0.471790 | 0.844604 | 0.619491 | 0.054* | |
H7C | 0.465444 | 0.761895 | 0.645062 | 0.054* | |
C8 | 0.5361 (3) | 0.8871 (2) | 0.4870 (3) | 0.0452 (13) | |
H8A | 0.492333 | 0.922612 | 0.472476 | 0.068* | |
H8B | 0.586638 | 0.890341 | 0.456183 | 0.068* | |
H8C | 0.554009 | 0.897320 | 0.534968 | 0.068* | |
C9 | 0.5187 (4) | 0.7927 (3) | 0.3503 (2) | 0.0456 (13) | |
H9A | 0.475279 | 0.825676 | 0.330445 | 0.068* | |
H9B | 0.524302 | 0.749593 | 0.320604 | 0.068* | |
H9C | 0.574773 | 0.817703 | 0.353096 | 0.068* | |
C10 | 0.4183 (3) | 0.6449 (3) | 0.3899 (2) | 0.0444 (13) | |
H10A | 0.355519 | 0.649373 | 0.382812 | 0.067* | |
H10B | 0.431411 | 0.596988 | 0.409703 | 0.067* | |
H10C | 0.448205 | 0.650298 | 0.345239 | 0.067* | |
C11 | 0.5660 (3) | 0.6194 (3) | 0.5293 (2) | 0.0278 (10) | |
C12 | 0.6913 (3) | 0.6181 (2) | 0.3746 (2) | 0.0286 (10) | |
C13 | 0.7413 (3) | 0.5637 (2) | 0.3961 (2) | 0.0304 (10) | |
C14 | 0.7606 (3) | 0.4963 (2) | 0.5252 (2) | 0.0278 (10) | |
H14A | 0.696377 | 0.496663 | 0.526437 | 0.033* | |
H14B | 0.779375 | 0.450965 | 0.501772 | 0.033* | |
C15 | 0.7957 (3) | 0.4971 (2) | 0.5998 (2) | 0.0358 (11) | |
H15A | 0.786109 | 0.448644 | 0.620841 | 0.043* | |
H15B | 0.859172 | 0.505579 | 0.598102 | 0.043* | |
C16 | 0.7548 (3) | 0.5546 (2) | 0.6466 (2) | 0.0328 (11) | |
H16A | 0.769533 | 0.544153 | 0.695734 | 0.039* | |
H16B | 0.690822 | 0.552699 | 0.641829 | 0.039* | |
C17 | 0.7331 (3) | 0.7017 (2) | 0.6814 (2) | 0.0292 (10) | |
C18 | 0.6833 (3) | 0.7532 (2) | 0.6539 (2) | 0.0267 (10) | |
C19 | 0.6439 (3) | 0.6191 (3) | 0.3059 (2) | 0.0397 (12) | |
H19A | 0.673889 | 0.587331 | 0.272713 | 0.060* | |
H19B | 0.642695 | 0.668917 | 0.287647 | 0.060* | |
H19C | 0.584335 | 0.601759 | 0.312578 | 0.060* | |
C20 | 0.7620 (3) | 0.4947 (3) | 0.3569 (2) | 0.0411 (12) | |
H20A | 0.733297 | 0.495786 | 0.311395 | 0.062* | |
H20B | 0.741350 | 0.452654 | 0.383458 | 0.062* | |
H20C | 0.824947 | 0.490988 | 0.350310 | 0.062* | |
C21 | 0.7475 (3) | 0.6871 (3) | 0.7574 (2) | 0.0378 (12) | |
H21A | 0.737458 | 0.731855 | 0.783949 | 0.057* | |
H21B | 0.807296 | 0.670606 | 0.764737 | 0.057* | |
H21C | 0.707132 | 0.649328 | 0.773176 | 0.057* | |
C22 | 0.6369 (3) | 0.8090 (3) | 0.6972 (2) | 0.0381 (11) | |
H22A | 0.676793 | 0.828725 | 0.732196 | 0.057* | |
H22B | 0.587285 | 0.786252 | 0.720573 | 0.057* | |
H22C | 0.616285 | 0.848535 | 0.667210 | 0.057* | |
P1 | 1.000000 | 0.50751 (9) | 0.750000 | 0.0338 (4) | |
P2 | 0.500000 | 0.56829 (10) | 0.750000 | 0.0361 (4) | |
F1 | 0.9262 (3) | 0.44789 (18) | 0.7508 (2) | 0.0895 (14) | |
F2 | 0.92696 (19) | 0.56827 (15) | 0.75048 (16) | 0.0518 (8) | |
F3 | 0.9995 (2) | 0.5074 (2) | 0.83285 (14) | 0.0700 (10) | |
F4 | 0.4168 (2) | 0.5668 (2) | 0.7027 (2) | 0.0808 (11) | |
F5 | 0.5402 (3) | 0.62895 (18) | 0.70149 (18) | 0.0727 (10) | |
F6 | 0.5418 (2) | 0.50624 (17) | 0.70251 (16) | 0.0670 (10) |
U11 | U22 | U33 | U12 | U13 | U23 | |
Ni1 | 0.0223 (3) | 0.0268 (3) | 0.0202 (3) | −0.0012 (2) | −0.0002 (2) | −0.0010 (2) |
Fe1 | 0.0216 (4) | 0.0250 (3) | 0.0201 (3) | 0.0001 (3) | 0.0002 (2) | 0.0023 (2) |
S1 | 0.0247 (6) | 0.0316 (6) | 0.0204 (5) | −0.0003 (5) | 0.0005 (4) | 0.0000 (4) |
S2 | 0.0229 (6) | 0.0327 (6) | 0.0286 (6) | 0.0013 (5) | 0.0008 (4) | −0.0049 (4) |
S3 | 0.0261 (6) | 0.0303 (6) | 0.0242 (5) | −0.0011 (5) | −0.0038 (4) | −0.0004 (4) |
S4 | 0.0269 (6) | 0.0269 (5) | 0.0231 (5) | −0.0013 (5) | −0.0007 (4) | −0.0010 (4) |
O1 | 0.036 (2) | 0.0321 (18) | 0.051 (2) | −0.0015 (15) | 0.0016 (16) | 0.0102 (15) |
C1 | 0.021 (2) | 0.028 (2) | 0.025 (2) | 0.0042 (18) | −0.0034 (17) | 0.0000 (17) |
C2 | 0.022 (2) | 0.030 (2) | 0.027 (2) | 0.0050 (18) | −0.0023 (18) | 0.0014 (18) |
C3 | 0.018 (2) | 0.029 (2) | 0.044 (3) | 0.0021 (19) | 0.001 (2) | 0.004 (2) |
C4 | 0.025 (3) | 0.043 (3) | 0.026 (2) | 0.009 (2) | 0.0030 (19) | 0.011 (2) |
C5 | 0.020 (2) | 0.039 (3) | 0.024 (2) | 0.006 (2) | −0.0028 (17) | −0.0011 (18) |
C6 | 0.027 (3) | 0.034 (2) | 0.046 (3) | −0.007 (2) | 0.003 (2) | 0.003 (2) |
C7 | 0.031 (3) | 0.045 (3) | 0.030 (2) | 0.005 (2) | 0.000 (2) | −0.010 (2) |
C8 | 0.028 (3) | 0.028 (2) | 0.079 (4) | −0.006 (2) | 0.007 (3) | 0.010 (2) |
C9 | 0.041 (3) | 0.060 (3) | 0.036 (3) | 0.014 (3) | 0.009 (2) | 0.021 (2) |
C10 | 0.036 (3) | 0.057 (3) | 0.040 (3) | 0.007 (3) | −0.013 (2) | −0.009 (2) |
C11 | 0.017 (2) | 0.039 (3) | 0.027 (2) | 0.001 (2) | 0.0023 (17) | 0.001 (2) |
C12 | 0.027 (3) | 0.033 (2) | 0.025 (2) | −0.002 (2) | 0.0040 (18) | −0.0060 (18) |
C13 | 0.029 (3) | 0.039 (3) | 0.024 (2) | 0.001 (2) | 0.0034 (19) | −0.0076 (19) |
C14 | 0.023 (2) | 0.023 (2) | 0.037 (2) | 0.0006 (18) | −0.0029 (19) | −0.0038 (18) |
C15 | 0.034 (3) | 0.032 (2) | 0.042 (3) | 0.001 (2) | −0.006 (2) | 0.004 (2) |
C16 | 0.037 (3) | 0.031 (2) | 0.031 (2) | 0.000 (2) | −0.003 (2) | 0.0036 (19) |
C17 | 0.029 (3) | 0.035 (2) | 0.023 (2) | −0.008 (2) | −0.0010 (19) | −0.0039 (19) |
C18 | 0.028 (3) | 0.030 (2) | 0.021 (2) | −0.007 (2) | −0.0012 (18) | −0.0052 (17) |
C19 | 0.041 (3) | 0.052 (3) | 0.026 (2) | −0.009 (3) | −0.002 (2) | −0.006 (2) |
C20 | 0.046 (3) | 0.045 (3) | 0.033 (2) | −0.001 (2) | 0.003 (2) | −0.014 (2) |
C21 | 0.044 (3) | 0.045 (3) | 0.025 (2) | −0.003 (2) | −0.005 (2) | 0.002 (2) |
C22 | 0.039 (3) | 0.048 (3) | 0.027 (2) | 0.003 (2) | −0.005 (2) | −0.010 (2) |
P1 | 0.0388 (11) | 0.0305 (9) | 0.0321 (9) | 0.000 | −0.0043 (7) | 0.000 |
P2 | 0.0311 (10) | 0.0423 (10) | 0.0350 (9) | 0.000 | −0.0006 (8) | 0.000 |
F1 | 0.112 (4) | 0.055 (2) | 0.102 (3) | −0.046 (2) | 0.036 (3) | −0.027 (2) |
F2 | 0.0310 (18) | 0.0563 (18) | 0.068 (2) | 0.0122 (14) | 0.0023 (14) | 0.0122 (15) |
F3 | 0.060 (2) | 0.115 (3) | 0.0349 (16) | 0.010 (2) | −0.0033 (15) | 0.0145 (17) |
F4 | 0.061 (2) | 0.090 (3) | 0.092 (3) | −0.011 (2) | −0.039 (2) | 0.017 (2) |
F5 | 0.090 (3) | 0.0526 (19) | 0.075 (2) | −0.0221 (19) | 0.016 (2) | 0.0109 (17) |
F6 | 0.089 (3) | 0.061 (2) | 0.0507 (18) | 0.0087 (19) | 0.0156 (18) | −0.0130 (15) |
Ni1—S3 | 2.1507 (11) | C10—H10A | 0.9800 |
Ni1—S2 | 2.1530 (12) | C10—H10B | 0.9800 |
Ni1—S4 | 2.1563 (12) | C10—H10C | 0.9800 |
Ni1—S1 | 2.1616 (11) | C12—C13 | 1.328 (6) |
Ni1—Fe1 | 2.9195 (8) | C12—C19 | 1.510 (6) |
Fe1—C11 | 1.768 (5) | C13—C20 | 1.509 (6) |
Fe1—C1 | 2.080 (4) | C14—C15 | 1.532 (6) |
Fe1—C5 | 2.098 (4) | C14—H14A | 0.9900 |
Fe1—C2 | 2.107 (4) | C14—H14B | 0.9900 |
Fe1—C3 | 2.126 (4) | C15—C16 | 1.524 (6) |
Fe1—C4 | 2.138 (4) | C15—H15A | 0.9900 |
Fe1—S1 | 2.3309 (12) | C15—H15B | 0.9900 |
Fe1—S4 | 2.3602 (12) | C16—H16A | 0.9900 |
S1—C12 | 1.798 (4) | C16—H16B | 0.9900 |
S2—C13 | 1.778 (4) | C17—C18 | 1.329 (6) |
S2—C14 | 1.833 (4) | C17—C21 | 1.501 (6) |
S3—C17 | 1.783 (5) | C18—C22 | 1.503 (6) |
S3—C16 | 1.825 (4) | C19—H19A | 0.9800 |
S4—C18 | 1.786 (4) | C19—H19B | 0.9800 |
O1—C11 | 1.149 (5) | C19—H19C | 0.9800 |
C1—C2 | 1.423 (6) | C20—H20A | 0.9800 |
C1—C5 | 1.432 (6) | C20—H20B | 0.9800 |
C1—C6 | 1.504 (6) | C20—H20C | 0.9800 |
C2—C3 | 1.434 (6) | C21—H21A | 0.9800 |
C2—C7 | 1.499 (6) | C21—H21B | 0.9800 |
C3—C4 | 1.404 (6) | C21—H21C | 0.9800 |
C3—C8 | 1.508 (6) | C22—H22A | 0.9800 |
C4—C5 | 1.429 (6) | C22—H22B | 0.9800 |
C4—C9 | 1.507 (6) | C22—H22C | 0.9800 |
C5—C10 | 1.493 (6) | P1—F1i | 1.579 (3) |
C6—H6A | 0.9800 | P1—F1 | 1.579 (3) |
C6—H6B | 0.9800 | P1—F2 | 1.585 (3) |
C6—H6C | 0.9800 | P1—F2i | 1.585 (3) |
C7—H7A | 0.9800 | P1—F3 | 1.592 (3) |
C7—H7B | 0.9800 | P1—F3i | 1.592 (3) |
C7—H7C | 0.9800 | P2—F4ii | 1.572 (3) |
C8—H8A | 0.9800 | P2—F4 | 1.572 (3) |
C8—H8B | 0.9800 | P2—F5ii | 1.580 (3) |
C8—H8C | 0.9800 | P2—F5 | 1.580 (3) |
C9—H9A | 0.9800 | P2—F6ii | 1.596 (3) |
C9—H9B | 0.9800 | P2—F6 | 1.596 (3) |
C9—H9C | 0.9800 | ||
S3—Ni1—S2 | 93.13 (4) | H8A—C8—H8B | 109.5 |
S3—Ni1—S4 | 91.41 (4) | C3—C8—H8C | 109.5 |
S2—Ni1—S4 | 174.38 (5) | H8A—C8—H8C | 109.5 |
S3—Ni1—S1 | 174.42 (5) | H8B—C8—H8C | 109.5 |
S2—Ni1—S1 | 91.42 (4) | C4—C9—H9A | 109.5 |
S4—Ni1—S1 | 83.87 (4) | C4—C9—H9B | 109.5 |
S3—Ni1—Fe1 | 122.53 (4) | H9A—C9—H9B | 109.5 |
S2—Ni1—Fe1 | 121.66 (4) | C4—C9—H9C | 109.5 |
S4—Ni1—Fe1 | 52.85 (3) | H9A—C9—H9C | 109.5 |
S1—Ni1—Fe1 | 52.04 (3) | H9B—C9—H9C | 109.5 |
C11—Fe1—C1 | 87.63 (18) | C5—C10—H10A | 109.5 |
C11—Fe1—C5 | 98.85 (18) | C5—C10—H10B | 109.5 |
C1—Fe1—C5 | 40.08 (15) | H10A—C10—H10B | 109.5 |
C11—Fe1—C2 | 114.69 (18) | C5—C10—H10C | 109.5 |
C1—Fe1—C2 | 39.73 (15) | H10A—C10—H10C | 109.5 |
C5—Fe1—C2 | 66.92 (16) | H10B—C10—H10C | 109.5 |
C11—Fe1—C3 | 152.97 (19) | O1—C11—Fe1 | 173.2 (4) |
C1—Fe1—C3 | 66.26 (16) | C13—C12—C19 | 124.2 (4) |
C5—Fe1—C3 | 66.07 (17) | C13—C12—S1 | 120.9 (3) |
C2—Fe1—C3 | 39.61 (16) | C19—C12—S1 | 114.7 (3) |
C11—Fe1—C4 | 137.02 (19) | C12—C13—C20 | 126.9 (4) |
C1—Fe1—C4 | 66.05 (16) | C12—C13—S2 | 118.0 (3) |
C5—Fe1—C4 | 39.42 (17) | C20—C13—S2 | 114.8 (3) |
C2—Fe1—C4 | 65.71 (16) | C15—C14—S2 | 111.4 (3) |
C3—Fe1—C4 | 38.43 (17) | C15—C14—H14A | 109.3 |
C11—Fe1—S1 | 95.64 (14) | S2—C14—H14A | 109.3 |
C1—Fe1—S1 | 148.36 (12) | C15—C14—H14B | 109.3 |
C5—Fe1—S1 | 108.58 (12) | S2—C14—H14B | 109.3 |
C2—Fe1—S1 | 149.63 (12) | H14A—C14—H14B | 108.0 |
C3—Fe1—S1 | 110.20 (12) | C16—C15—C14 | 114.4 (4) |
C4—Fe1—S1 | 91.47 (12) | C16—C15—H15A | 108.7 |
C11—Fe1—S4 | 101.72 (14) | C14—C15—H15A | 108.7 |
C1—Fe1—S4 | 134.25 (11) | C16—C15—H15B | 108.7 |
C5—Fe1—S4 | 158.40 (12) | C14—C15—H15B | 108.7 |
C2—Fe1—S4 | 98.20 (12) | H15A—C15—H15B | 107.6 |
C3—Fe1—S4 | 92.43 (13) | C15—C16—S3 | 110.7 (3) |
C4—Fe1—S4 | 121.08 (13) | C15—C16—H16A | 109.5 |
S1—Fe1—S4 | 75.92 (4) | S3—C16—H16A | 109.5 |
C11—Fe1—Ni1 | 71.28 (14) | C15—C16—H16B | 109.5 |
C1—Fe1—Ni1 | 157.04 (11) | S3—C16—H16B | 109.5 |
C5—Fe1—Ni1 | 149.87 (12) | H16A—C16—H16B | 108.1 |
C2—Fe1—Ni1 | 143.21 (12) | C18—C17—C21 | 126.8 (4) |
C3—Fe1—Ni1 | 132.80 (12) | C18—C17—S3 | 117.8 (3) |
C4—Fe1—Ni1 | 136.25 (12) | C21—C17—S3 | 115.3 (3) |
S1—Fe1—Ni1 | 46.99 (3) | C17—C18—C22 | 122.7 (4) |
S4—Fe1—Ni1 | 46.74 (3) | C17—C18—S4 | 121.1 (3) |
C12—S1—Ni1 | 102.40 (15) | C22—C18—S4 | 116.0 (3) |
C12—S1—Fe1 | 117.49 (15) | C12—C19—H19A | 109.5 |
Ni1—S1—Fe1 | 80.97 (4) | C12—C19—H19B | 109.5 |
C13—S2—C14 | 101.1 (2) | H19A—C19—H19B | 109.5 |
C13—S2—Ni1 | 104.38 (15) | C12—C19—H19C | 109.5 |
C14—S2—Ni1 | 107.23 (14) | H19A—C19—H19C | 109.5 |
C17—S3—C16 | 102.0 (2) | H19B—C19—H19C | 109.5 |
C17—S3—Ni1 | 104.64 (15) | C13—C20—H20A | 109.5 |
C16—S3—Ni1 | 107.48 (15) | C13—C20—H20B | 109.5 |
C18—S4—Ni1 | 103.04 (15) | H20A—C20—H20B | 109.5 |
C18—S4—Fe1 | 120.33 (15) | C13—C20—H20C | 109.5 |
Ni1—S4—Fe1 | 80.41 (4) | H20A—C20—H20C | 109.5 |
C2—C1—C5 | 108.6 (4) | H20B—C20—H20C | 109.5 |
C2—C1—C6 | 124.7 (4) | C17—C21—H21A | 109.5 |
C5—C1—C6 | 126.4 (4) | C17—C21—H21B | 109.5 |
C2—C1—Fe1 | 71.2 (2) | H21A—C21—H21B | 109.5 |
C5—C1—Fe1 | 70.6 (2) | C17—C21—H21C | 109.5 |
C6—C1—Fe1 | 128.5 (3) | H21A—C21—H21C | 109.5 |
C1—C2—C3 | 107.2 (4) | H21B—C21—H21C | 109.5 |
C1—C2—C7 | 124.5 (4) | C18—C22—H22A | 109.5 |
C3—C2—C7 | 128.1 (4) | C18—C22—H22B | 109.5 |
C1—C2—Fe1 | 69.1 (2) | H22A—C22—H22B | 109.5 |
C3—C2—Fe1 | 70.9 (2) | C18—C22—H22C | 109.5 |
C7—C2—Fe1 | 129.7 (3) | H22A—C22—H22C | 109.5 |
C4—C3—C2 | 108.5 (4) | H22B—C22—H22C | 109.5 |
C4—C3—C8 | 125.2 (4) | F1i—P1—F1 | 92.2 (3) |
C2—C3—C8 | 126.1 (4) | F1i—P1—F2 | 179.1 (2) |
C4—C3—Fe1 | 71.3 (2) | F1—P1—F2 | 88.70 (19) |
C2—C3—Fe1 | 69.5 (2) | F1i—P1—F2i | 88.70 (19) |
C8—C3—Fe1 | 128.5 (3) | F1—P1—F2i | 179.11 (19) |
C3—C4—C5 | 108.8 (4) | F2—P1—F2i | 90.4 (2) |
C3—C4—C9 | 126.0 (4) | F1i—P1—F3 | 90.73 (19) |
C5—C4—C9 | 125.2 (4) | F1—P1—F3 | 89.21 (19) |
C3—C4—Fe1 | 70.3 (2) | F2—P1—F3 | 89.51 (17) |
C5—C4—Fe1 | 68.8 (2) | F2i—P1—F3 | 90.56 (17) |
C9—C4—Fe1 | 128.9 (3) | F1i—P1—F3i | 89.21 (19) |
C4—C5—C1 | 107.0 (4) | F1—P1—F3i | 90.73 (19) |
C4—C5—C10 | 127.9 (4) | F2—P1—F3i | 90.56 (17) |
C1—C5—C10 | 124.6 (4) | F2i—P1—F3i | 89.51 (17) |
C4—C5—Fe1 | 71.8 (2) | F3—P1—F3i | 179.9 (3) |
C1—C5—Fe1 | 69.3 (2) | F4ii—P2—F4 | 178.0 (3) |
C10—C5—Fe1 | 130.4 (3) | F4ii—P2—F5ii | 89.5 (2) |
C1—C6—H6A | 109.5 | F4—P2—F5ii | 91.9 (2) |
C1—C6—H6B | 109.5 | F4ii—P2—F5 | 91.9 (2) |
H6A—C6—H6B | 109.5 | F4—P2—F5 | 89.5 (2) |
C1—C6—H6C | 109.5 | F5ii—P2—F5 | 90.2 (3) |
H6A—C6—H6C | 109.5 | F4ii—P2—F6ii | 89.2 (2) |
H6B—C6—H6C | 109.5 | F4—P2—F6ii | 89.4 (2) |
C2—C7—H7A | 109.5 | F5ii—P2—F6ii | 90.47 (18) |
C2—C7—H7B | 109.5 | F5—P2—F6ii | 178.67 (19) |
H7A—C7—H7B | 109.5 | F4ii—P2—F6 | 89.4 (2) |
C2—C7—H7C | 109.5 | F4—P2—F6 | 89.2 (2) |
H7A—C7—H7C | 109.5 | F5ii—P2—F6 | 178.66 (19) |
H7B—C7—H7C | 109.5 | F5—P2—F6 | 90.47 (18) |
C3—C8—H8A | 109.5 | F6ii—P2—F6 | 88.8 (3) |
C3—C8—H8B | 109.5 | ||
C5—C1—C2—C3 | 0.0 (5) | C2—C1—C5—C10 | −173.1 (4) |
C6—C1—C2—C3 | −174.6 (4) | C6—C1—C5—C10 | 1.4 (7) |
Fe1—C1—C2—C3 | 61.0 (3) | Fe1—C1—C5—C10 | 125.5 (4) |
C5—C1—C2—C7 | 174.4 (4) | C2—C1—C5—Fe1 | 61.4 (3) |
C6—C1—C2—C7 | −0.2 (7) | C6—C1—C5—Fe1 | −124.2 (4) |
Fe1—C1—C2—C7 | −124.5 (4) | Ni1—S1—C12—C13 | −10.7 (4) |
C5—C1—C2—Fe1 | −61.0 (3) | Fe1—S1—C12—C13 | −96.8 (4) |
C6—C1—C2—Fe1 | 124.4 (4) | Ni1—S1—C12—C19 | 173.1 (3) |
C1—C2—C3—C4 | 1.0 (5) | Fe1—S1—C12—C19 | 86.9 (3) |
C7—C2—C3—C4 | −173.2 (4) | C19—C12—C13—C20 | 1.5 (8) |
Fe1—C2—C3—C4 | 60.9 (3) | S1—C12—C13—C20 | −174.4 (4) |
C1—C2—C3—C8 | 176.8 (4) | C19—C12—C13—S2 | 174.9 (3) |
C7—C2—C3—C8 | 2.6 (8) | S1—C12—C13—S2 | −1.0 (5) |
Fe1—C2—C3—C8 | −123.3 (5) | C14—S2—C13—C12 | 123.5 (4) |
C1—C2—C3—Fe1 | −59.9 (3) | Ni1—S2—C13—C12 | 12.2 (4) |
C7—C2—C3—Fe1 | 125.9 (5) | C14—S2—C13—C20 | −62.3 (4) |
C2—C3—C4—C5 | −1.6 (5) | Ni1—S2—C13—C20 | −173.6 (3) |
C8—C3—C4—C5 | −177.4 (4) | C13—S2—C14—C15 | −174.9 (3) |
Fe1—C3—C4—C5 | 58.2 (3) | Ni1—S2—C14—C15 | −65.9 (3) |
C2—C3—C4—C9 | 175.9 (4) | S2—C14—C15—C16 | 72.5 (4) |
C8—C3—C4—C9 | 0.1 (7) | C14—C15—C16—S3 | −73.0 (4) |
Fe1—C3—C4—C9 | −124.3 (5) | C17—S3—C16—C15 | 177.2 (3) |
C2—C3—C4—Fe1 | −59.7 (3) | Ni1—S3—C16—C15 | 67.5 (3) |
C8—C3—C4—Fe1 | 124.4 (5) | C16—S3—C17—C18 | −122.3 (4) |
C3—C4—C5—C1 | 1.6 (5) | Ni1—S3—C17—C18 | −10.4 (4) |
C9—C4—C5—C1 | −176.0 (4) | C16—S3—C17—C21 | 60.1 (4) |
Fe1—C4—C5—C1 | 60.7 (3) | Ni1—S3—C17—C21 | 172.0 (3) |
C3—C4—C5—C10 | 173.4 (4) | C21—C17—C18—C22 | 3.9 (7) |
C9—C4—C5—C10 | −4.2 (7) | S3—C17—C18—C22 | −173.4 (3) |
Fe1—C4—C5—C10 | −127.5 (5) | C21—C17—C18—S4 | 178.1 (4) |
C3—C4—C5—Fe1 | −59.1 (3) | S3—C17—C18—S4 | 0.8 (5) |
C9—C4—C5—Fe1 | 123.3 (4) | Ni1—S4—C18—C17 | 9.1 (4) |
C2—C1—C5—C4 | −1.0 (5) | Fe1—S4—C18—C17 | 95.5 (4) |
C6—C1—C5—C4 | 173.5 (4) | Ni1—S4—C18—C22 | −176.3 (3) |
Fe1—C1—C5—C4 | −62.3 (3) | Fe1—S4—C18—C22 | −89.9 (3) |
Symmetry codes: (i) −x+2, y, −z+3/2; (ii) −x+1, y, −z+3/2. |
Acknowledgements
We thank Mitchell J. Kerr for preparing a sample of Ni(S2C2Me2)2 used in the synthesis.
Funding information
Funding for this research was provided by: Natural Sciences and Engineering Research Council of Canada; University of Toronto.
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