metal-organic compounds
[2,2′-Bis(diphenylphosphanyl)-1,1′-binaphthyl-κ2P,P′]dichloridoplatinum(II) acetonitrile trisolvate
aDepartment of Chemistry, University of Manitoba, Winnipeg, Manitoba, R3T 2N2, Canada
*Correspondence e-mail: david.herbert@umanitoba.ca
The 2(C44H32P2)]·3CH3CN, has been determined. The comprises a single molecule of the title compound co-crystallized with three acetonitrile solvent molecules. Four molecules are observed in the with R and S enantiomers present in a 2:2 ratio. Evidence of intramolecular π-stacking is observed with no discernable intermolecular interactions.
(150 K) of the racemic title compound, [PtClKeywords: crystal structure; racemate; platinum; metallic complex.
CCDC reference: 2020002
Structure description
The increasing demand for chiral compounds in the pharmaceutical, agrochemical and food industries has driven the development of chiral ligands and coordination complexes, which can perform asymmetric catalysis to yield desirable organic molecules with high enantioselectivities (Noyori, 1994). Popular design motifs for chiral ligands are those that incorporate an atropisomeric backbone featuring C2 symmetry (Genet et al., 2014). 2,2′-Bis(diphenylphosphino)-1,1′-binaphthyl (BINAP, Fig. 1), first developed by Noyori and Takaya in 1980 (Miyashita et al., 1980), fits this brief. In the decades since its appearance in the literature, BINAP derivatives have been used to construct a wide variety of coordination complexes, typically involving late transition metals (Misra et al., 2017). Palladium complexes of BINAP have been historically amongst the most common (Pereira et al., 2013). They are exceptionally popular due to their successful and versatile application as catalysts in a variety of organic reactions such as the enantioselective benzoylation of (Iwata et al., 2002) and asymmetric alkylations (Guerrero-Ríos & Martin, 2014). Although less common than complexes of the second-row metal Pd, atropisomers of (BINAP)PtCl2 (Fig. 2) have found use in catalytic reactions such as enantioselective Baeyer–Villiger oxidations of cyclic with hydrogen peroxide (Strukul et al., 1997) and as precatalysts for asymmetric carbonyl-ene reactions (Doherty et al., 2006). Enantiomeric complexes of the formula L2PtCl2 including (BINAP)PtCl2 have also been examined for their cytotoxic activity against cancer cell lines and their ability to bind to the human telomeric sequence folded in the G-quadruplex structure (Bombard et al., 2010). There is therefore significant interest in elucidating the solid-state structures of these types of compounds to help guide future design strategies appropriate for particular applications.
While the structure of {(R)-BINAP}PtCl2 has been described as a dichloromethane solvate in the orthorhombic P212121 (Doherty et al., 2006), the corresponding racemate (racBINAP)PtCl2 has yet to be structurally characterized. We report here the solid-state of (racBINAP)PtCl2 determined via single-crystal X-ray diffraction and discuss its structural properties. The solid-state structure of [racBINAP]PtCl2 obtained by modelling single-crystal X-ray diffraction data is shown in Fig. 3 with selected bonds and angles in Table 1. The compound crystallizes in the monoclinic P21/c with three acetonitrile solvent molecules present within the The complex adopts a slightly distorted square-planar coordination geometry about the central PtII atom with trans atoms situated at bond angles of 171°, resulting in a τ4 value of 0.12. The bidentate BINAP ligand coordinates to Pt with a bite angle (P1—Pt1—P2) of 92.87 (3)°, consistent with typical literature values of approximately 93° (Birkholz et al., 2009). Evidence of intramolecular π stacking between naphthyl and phenyl substituents is observed, generating close contacts ranging from 3.2 to 4.0 Å. Fig. 4 shows the distances between calculated centroids of two of the phosphorus phenyl substituents and the nearest six membered carbon ring of a napthyl unit.
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Compared to the Pd analogue (Véron et al., 2013), the Pt—Cl bond lengths [Pt1—Cl1 = 2.3518 (8) Å; Pt1—Cl2 = 2.3536 (8) Å]) are only around 0.01 Å longer. The two Pt—Cl distances are also statistically indistinguishable, implying similar orbital overlap between the PtII metal centre and the strong trans phosphine donors. An only slightly acute Cl1—Pt1—Cl2 angle of 87.44 (3)° is observed, indicating slight steric repulsion from the diphenylphosphine arms. Angles closer to the ideal of 90° are seen between cis-disposed phosphorus and chlorine atoms. The bond lengths involving the Pt metal centre are similar to those in the enantiopure (R-BINAP)PtCl2 (Doherty et al., 2006); however, deviations are observed in several of the angles.
In a single ), with two of each enantiomer present. Interestingly, no significant intermolecular interactions are present within the sum of the van der Waals radii. The closest intermolecular interaction stems from hydrogen bonds between neighbouring acetonitrile solvent molecules. These interactions are all greater than 3.40 Å and so were not investigated any further. Distances of 3.30 to 3.70 Å can be observed between naphthyl carbon atoms of neighbouring complexes; however, the arrangement is not stacked and so not likely to be significant.
four molecules can be found (Fig. 5Synthesis and crystallization
Crystals of (racBINAP)PtCl2 were obtained as a side-product from a reaction mixture of (COD)PtCl2 and a tridentate, diarylamido-N,N-phenanthridine-based ligand (Mandapati et al., 2019). BINAP was used to construct this ligand via a Pd-cross coupling reaction and was not completely removed from the proligand before metalation. Crystal-structure data were collected from a multi-faceted crystal of suitable size and quality selected from a representative sample of crystals of the same habit using an optical microscope.
Refinement
Crystal data, data collection and structure .
details are summarized in Table 2Structural data
CCDC reference: 2020002
https://doi.org/10.1107/S2414314620010482/zq2254sup1.cif
contains datablock I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314620010482/zq2254Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S2414314620010482/zq2254Isup3.cml
Supporting tables and experimental information. DOI: https://doi.org/10.1107/S2414314620010482/zq2254sup4.pdf
Data collection: APEX3 and SAINT (Bruker, 2016); cell
APEX3 (Bruker, 2016); data reduction: SAINT (Bruker, 2016); program(s) used to solve structure: ShelXT (Sheldrick, 2015a); program(s) used to refine structure: SHELXL (Sheldrick, 2015b); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009) and PLATON (Spek, 2020).[PtCl2(C44H32P2)]·3C2H3N | F(000) = 2016 |
Mr = 1011.79 | Dx = 1.546 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
a = 11.3681 (4) Å | Cell parameters from 9175 reflections |
b = 12.5001 (4) Å | θ = 2.4–30.5° |
c = 30.7944 (11) Å | µ = 3.46 mm−1 |
β = 96.439 (2)° | T = 150 K |
V = 4348.4 (3) Å3 | Block, orange |
Z = 4 | 0.39 × 0.19 × 0.13 mm |
Bruker D8 Quest ECO CMOS diffractometer | 11205 reflections with I > 2σ(I) |
Radiation source: fine–focus tube | Rint = 0.079 |
φ and ω scans | θmax = 30.6°, θmin = 2.4° |
Absorption correction: multi-scan (SADABS; Bruker, 2016) | h = −16→16 |
Tmin = 0.553, Tmax = 0.746 | k = −17→17 |
142092 measured reflections | l = −44→44 |
13302 independent reflections |
Refinement on F2 | Primary atom site location: dual |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.036 | H-atom parameters constrained |
wR(F2) = 0.072 | w = 1/[σ2(Fo2) + (0.0143P)2 + 16.231P] where P = (Fo2 + 2Fc2)/3 |
S = 1.09 | (Δ/σ)max = 0.003 |
13302 reflections | Δρmax = 1.25 e Å−3 |
526 parameters | Δρmin = −1.49 e Å−3 |
18 restraints |
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. |
Refinement. A single-crystal was mounted on a MiTiGen loop and data collection was carried out in a cold stream of nitrogen. All diffractometer manipulations were carried out using Bruker APEX3 software (Bruker-AXS, 2016). Structure solution and refinement were carried out in the OLEX2 (Dolomanov et al., 2009) program using SHELXT (Sheldrick, 2015a) and SHELXL (Sheldrick, 2015b) softwares. All hydrogen atoms within the structure were placed in geometrically idealized positions and were constrained to ride on their parent atoms (C–H = 0.95 Å). The absence of additional symmetry was confirmed using ADDSYM incorporated in the PLATON program (Spek, 2020). The presence of inter- or intramolecular hydrogen bonds was probed, but not observed below a limit of 3.40 Å with a D–H···A angle of less than 120°. |
x | y | z | Uiso*/Ueq | ||
C1 | 0.2521 (3) | 0.1586 (3) | 0.40291 (10) | 0.0175 (6) | |
C2 | 0.2621 (3) | 0.0859 (3) | 0.43763 (11) | 0.0218 (7) | |
H2 | 0.302614 | 0.020146 | 0.435151 | 0.026* | |
C3 | 0.2128 (3) | 0.1098 (4) | 0.47570 (12) | 0.0309 (9) | |
H3 | 0.220148 | 0.060652 | 0.499378 | 0.037* | |
C4 | 0.1533 (3) | 0.2046 (4) | 0.47912 (13) | 0.0367 (10) | |
H4 | 0.119892 | 0.220626 | 0.505285 | 0.044* | |
C5 | 0.1415 (3) | 0.2765 (4) | 0.44510 (14) | 0.0350 (9) | |
H5 | 0.100082 | 0.341684 | 0.447939 | 0.042* | |
C6 | 0.1902 (3) | 0.2542 (3) | 0.40638 (12) | 0.0237 (7) | |
H6 | 0.181422 | 0.303483 | 0.382742 | 0.028* | |
C7 | 0.2479 (3) | 0.0151 (3) | 0.32864 (10) | 0.0159 (6) | |
C8 | 0.1587 (3) | −0.0380 (3) | 0.34728 (12) | 0.0231 (7) | |
H8 | 0.135936 | −0.014840 | 0.374495 | 0.028* | |
C9 | 0.1026 (4) | −0.1259 (3) | 0.32576 (13) | 0.0305 (8) | |
H9 | 0.041022 | −0.161847 | 0.338345 | 0.037* | |
C10 | 0.1359 (3) | −0.1609 (3) | 0.28637 (13) | 0.0272 (8) | |
H10 | 0.098355 | −0.221397 | 0.272208 | 0.033* | |
C11 | 0.2243 (3) | −0.1073 (3) | 0.26758 (11) | 0.0228 (7) | |
H11 | 0.247682 | −0.131209 | 0.240550 | 0.027* | |
C12 | 0.2784 (3) | −0.0190 (3) | 0.28826 (10) | 0.0182 (6) | |
H12 | 0.337044 | 0.018842 | 0.274784 | 0.022* | |
C13 | 0.4718 (3) | 0.0833 (2) | 0.37430 (9) | 0.0123 (5) | |
C14 | 0.5161 (3) | −0.0090 (2) | 0.35467 (10) | 0.0139 (6) | |
H14 | 0.464981 | −0.048898 | 0.334186 | 0.017* | |
C15 | 0.6304 (3) | −0.0415 (2) | 0.36460 (10) | 0.0161 (6) | |
H15 | 0.657915 | −0.102753 | 0.350507 | 0.019* | |
C16 | 0.7085 (3) | 0.0145 (2) | 0.39555 (10) | 0.0147 (6) | |
C17 | 0.8273 (3) | −0.0188 (3) | 0.40605 (11) | 0.0215 (7) | |
H17 | 0.855246 | −0.080496 | 0.392353 | 0.026* | |
C18 | 0.9025 (3) | 0.0369 (3) | 0.43572 (12) | 0.0247 (7) | |
H18 | 0.981974 | 0.013862 | 0.442746 | 0.030* | |
C19 | 0.8609 (3) | 0.1288 (3) | 0.45579 (11) | 0.0232 (7) | |
H19 | 0.913246 | 0.167801 | 0.476178 | 0.028* | |
C20 | 0.7463 (3) | 0.1628 (3) | 0.44639 (10) | 0.0176 (6) | |
H20 | 0.720221 | 0.224811 | 0.460328 | 0.021* | |
C21 | 0.6662 (3) | 0.1061 (2) | 0.41602 (10) | 0.0140 (6) | |
C22 | 0.5464 (3) | 0.1407 (2) | 0.40469 (9) | 0.0123 (5) | |
C23 | 0.5052 (3) | 0.2397 (2) | 0.42572 (9) | 0.0131 (5) | |
C24 | 0.4825 (3) | 0.3333 (2) | 0.40198 (9) | 0.0128 (5) | |
C25 | 0.4400 (3) | 0.4247 (2) | 0.42271 (10) | 0.0158 (6) | |
H25 | 0.426277 | 0.489099 | 0.406547 | 0.019* | |
C26 | 0.4186 (3) | 0.4219 (3) | 0.46534 (10) | 0.0171 (6) | |
H26 | 0.387404 | 0.483429 | 0.478066 | 0.020* | |
C27 | 0.4419 (3) | 0.3292 (2) | 0.49086 (10) | 0.0148 (6) | |
C28 | 0.4214 (3) | 0.3262 (3) | 0.53539 (10) | 0.0195 (6) | |
H28 | 0.391311 | 0.387923 | 0.548380 | 0.023* | |
C29 | 0.4443 (3) | 0.2361 (3) | 0.55992 (10) | 0.0219 (6) | |
H29 | 0.429616 | 0.234811 | 0.589678 | 0.026* | |
C30 | 0.4899 (3) | 0.1448 (3) | 0.54072 (10) | 0.0199 (6) | |
H30 | 0.505993 | 0.082119 | 0.557782 | 0.024* | |
C31 | 0.5114 (3) | 0.1453 (2) | 0.49788 (10) | 0.0162 (6) | |
H31 | 0.542657 | 0.083009 | 0.485726 | 0.019* | |
C32 | 0.4877 (3) | 0.2373 (2) | 0.47126 (9) | 0.0128 (5) | |
C33 | 0.4989 (3) | 0.4806 (3) | 0.33082 (10) | 0.0168 (6) | |
C34 | 0.3962 (3) | 0.5418 (3) | 0.33043 (11) | 0.0203 (7) | |
H34 | 0.325124 | 0.509001 | 0.337272 | 0.024* | |
C35 | 0.3965 (4) | 0.6497 (3) | 0.32019 (11) | 0.0252 (7) | |
H35 | 0.326574 | 0.691091 | 0.320763 | 0.030* | |
C36 | 0.4990 (4) | 0.6970 (3) | 0.30914 (12) | 0.0307 (9) | |
H36 | 0.499050 | 0.770707 | 0.301582 | 0.037* | |
C37 | 0.6009 (4) | 0.6378 (3) | 0.30905 (13) | 0.0302 (8) | |
H37 | 0.671299 | 0.670836 | 0.301692 | 0.036* | |
C38 | 0.6014 (3) | 0.5294 (3) | 0.31972 (12) | 0.0236 (7) | |
H38 | 0.671870 | 0.488684 | 0.319405 | 0.028* | |
C39 | 0.6310 (3) | 0.2806 (2) | 0.33394 (10) | 0.0154 (6) | |
C40 | 0.6356 (3) | 0.2005 (3) | 0.30250 (10) | 0.0174 (6) | |
H40 | 0.565041 | 0.177771 | 0.285560 | 0.021* | |
C41 | 0.7432 (3) | 0.1544 (3) | 0.29603 (12) | 0.0245 (7) | |
H41 | 0.745961 | 0.099678 | 0.274747 | 0.029* | |
C42 | 0.8462 (3) | 0.1873 (3) | 0.32027 (13) | 0.0265 (8) | |
H42 | 0.919463 | 0.154959 | 0.315777 | 0.032* | |
C43 | 0.8429 (3) | 0.2678 (3) | 0.35128 (12) | 0.0257 (7) | |
H43 | 0.914178 | 0.291634 | 0.367440 | 0.031* | |
C44 | 0.7358 (3) | 0.3132 (3) | 0.35860 (11) | 0.0207 (7) | |
H44 | 0.733391 | 0.366573 | 0.380423 | 0.025* | |
C45 | 0.0714 (4) | 0.5037 (4) | 0.32714 (18) | 0.0429 (11) | |
C46 | 0.0589 (4) | 0.5036 (4) | 0.28013 (17) | 0.0473 (12) | |
H46A | 0.122395 | 0.546344 | 0.269788 | 0.071* | |
H46B | −0.017963 | 0.534298 | 0.269059 | 0.071* | |
H46C | 0.063717 | 0.429940 | 0.269533 | 0.071* | |
C47 | 0.8616 (4) | 0.2521 (4) | 0.56830 (15) | 0.0408 (10) | |
C48 | 0.7545 (5) | 0.3114 (6) | 0.5712 (2) | 0.0727 (19) | |
H48A | 0.774248 | 0.385073 | 0.580191 | 0.109* | |
H48B | 0.709346 | 0.277725 | 0.592839 | 0.109* | |
H48C | 0.706889 | 0.311867 | 0.542659 | 0.109* | |
Cl1 | 0.14268 (7) | 0.21270 (7) | 0.27128 (3) | 0.02745 (19) | |
Cl2 | 0.34019 (8) | 0.38528 (6) | 0.24790 (2) | 0.02091 (16) | |
N1 | 0.0830 (6) | 0.5016 (5) | 0.3642 (2) | 0.0805 (17) | |
N2 | 0.9465 (5) | 0.2073 (4) | 0.56653 (16) | 0.0643 (14) | |
P1 | 0.32310 (7) | 0.13146 (6) | 0.35451 (2) | 0.01190 (14) | |
P2 | 0.49025 (7) | 0.33817 (6) | 0.34282 (2) | 0.01222 (14) | |
Pt1 | 0.32836 (2) | 0.26525 (2) | 0.30614 (2) | 0.01414 (3) | |
C51 | 0.8660 (10) | 0.5704 (9) | 0.4281 (4) | 0.144 (3) | |
H51A | 0.894116 | 0.636153 | 0.443150 | 0.216* | |
H51B | 0.790640 | 0.584487 | 0.410230 | 0.216* | |
H51C | 0.924592 | 0.546071 | 0.409218 | 0.216* | |
C52 | 0.8493 (11) | 0.4896 (11) | 0.4595 (5) | 0.142 (3) | |
N3 | 0.8066 (10) | 0.4370 (8) | 0.4778 (4) | 0.144 (3) |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0155 (14) | 0.0225 (16) | 0.0150 (14) | −0.0041 (12) | 0.0049 (11) | −0.0059 (12) |
C2 | 0.0181 (16) | 0.0295 (18) | 0.0180 (15) | −0.0067 (13) | 0.0028 (12) | 0.0005 (13) |
C3 | 0.0261 (19) | 0.053 (3) | 0.0149 (16) | −0.0179 (17) | 0.0061 (14) | −0.0020 (15) |
C4 | 0.0241 (18) | 0.066 (3) | 0.0225 (18) | −0.0163 (19) | 0.0125 (15) | −0.0214 (18) |
C5 | 0.0227 (18) | 0.045 (2) | 0.039 (2) | −0.0012 (17) | 0.0096 (16) | −0.0223 (19) |
C6 | 0.0174 (15) | 0.0272 (19) | 0.0268 (17) | −0.0012 (13) | 0.0036 (12) | −0.0075 (14) |
C7 | 0.0163 (14) | 0.0158 (15) | 0.0148 (14) | −0.0016 (11) | −0.0016 (11) | 0.0010 (11) |
C8 | 0.0231 (17) | 0.0245 (18) | 0.0220 (16) | −0.0072 (13) | 0.0038 (13) | −0.0031 (13) |
C9 | 0.031 (2) | 0.028 (2) | 0.032 (2) | −0.0154 (16) | 0.0050 (16) | −0.0027 (15) |
C10 | 0.0298 (19) | 0.0165 (16) | 0.034 (2) | −0.0084 (14) | −0.0038 (15) | −0.0042 (14) |
C11 | 0.0272 (18) | 0.0200 (16) | 0.0202 (16) | −0.0010 (13) | −0.0010 (13) | −0.0050 (13) |
C12 | 0.0213 (16) | 0.0164 (15) | 0.0169 (15) | 0.0004 (12) | 0.0023 (12) | −0.0017 (11) |
C13 | 0.0143 (13) | 0.0108 (13) | 0.0122 (13) | −0.0014 (10) | 0.0030 (10) | 0.0018 (10) |
C14 | 0.0184 (15) | 0.0116 (13) | 0.0116 (13) | −0.0014 (11) | 0.0017 (11) | −0.0012 (10) |
C15 | 0.0203 (15) | 0.0139 (14) | 0.0147 (14) | 0.0022 (11) | 0.0042 (11) | −0.0017 (11) |
C16 | 0.0140 (14) | 0.0157 (14) | 0.0152 (14) | 0.0018 (11) | 0.0045 (11) | 0.0007 (11) |
C17 | 0.0186 (16) | 0.0241 (17) | 0.0222 (16) | 0.0047 (13) | 0.0035 (13) | −0.0016 (13) |
C18 | 0.0121 (15) | 0.035 (2) | 0.0271 (18) | 0.0024 (13) | 0.0014 (13) | 0.0002 (15) |
C19 | 0.0176 (16) | 0.0303 (19) | 0.0211 (16) | −0.0035 (13) | −0.0002 (13) | −0.0020 (13) |
C20 | 0.0150 (14) | 0.0200 (15) | 0.0182 (15) | −0.0007 (12) | 0.0032 (11) | −0.0015 (12) |
C21 | 0.0138 (14) | 0.0150 (14) | 0.0134 (13) | −0.0017 (11) | 0.0031 (11) | 0.0010 (11) |
C22 | 0.0153 (14) | 0.0098 (13) | 0.0124 (13) | −0.0026 (10) | 0.0038 (10) | 0.0004 (10) |
C23 | 0.0143 (13) | 0.0111 (13) | 0.0141 (13) | −0.0011 (11) | 0.0020 (10) | −0.0004 (10) |
C24 | 0.0126 (13) | 0.0125 (13) | 0.0129 (13) | −0.0020 (10) | 0.0005 (10) | −0.0012 (10) |
C25 | 0.0176 (15) | 0.0136 (14) | 0.0159 (14) | 0.0016 (11) | 0.0008 (11) | 0.0012 (11) |
C26 | 0.0212 (16) | 0.0140 (14) | 0.0162 (14) | 0.0022 (12) | 0.0031 (12) | −0.0026 (11) |
C27 | 0.0158 (14) | 0.0146 (14) | 0.0143 (14) | −0.0012 (11) | 0.0034 (11) | −0.0025 (11) |
C28 | 0.0240 (17) | 0.0196 (16) | 0.0161 (15) | −0.0012 (13) | 0.0068 (12) | −0.0045 (12) |
C29 | 0.0301 (17) | 0.0230 (16) | 0.0136 (13) | −0.0032 (14) | 0.0061 (12) | −0.0017 (12) |
C30 | 0.0286 (18) | 0.0169 (15) | 0.0144 (14) | −0.0003 (13) | 0.0032 (13) | 0.0026 (11) |
C31 | 0.0195 (15) | 0.0138 (14) | 0.0154 (14) | −0.0007 (11) | 0.0020 (11) | 0.0002 (11) |
C32 | 0.0135 (12) | 0.0119 (13) | 0.0129 (12) | −0.0012 (11) | 0.0010 (10) | −0.0007 (10) |
C33 | 0.0250 (16) | 0.0147 (14) | 0.0105 (13) | −0.0017 (12) | 0.0009 (12) | 0.0013 (10) |
C34 | 0.0293 (18) | 0.0139 (15) | 0.0175 (15) | 0.0008 (13) | 0.0015 (13) | 0.0026 (11) |
C35 | 0.040 (2) | 0.0167 (16) | 0.0188 (16) | 0.0063 (14) | 0.0027 (14) | 0.0001 (12) |
C36 | 0.059 (3) | 0.0129 (15) | 0.0209 (17) | −0.0026 (16) | 0.0075 (17) | 0.0009 (13) |
C37 | 0.043 (2) | 0.0193 (17) | 0.0300 (19) | −0.0100 (16) | 0.0134 (17) | 0.0004 (14) |
C38 | 0.0307 (19) | 0.0180 (16) | 0.0238 (17) | −0.0045 (14) | 0.0108 (14) | 0.0023 (13) |
C39 | 0.0167 (14) | 0.0157 (15) | 0.0142 (13) | −0.0010 (11) | 0.0037 (11) | 0.0025 (11) |
C40 | 0.0206 (15) | 0.0154 (14) | 0.0172 (14) | −0.0013 (12) | 0.0058 (12) | 0.0018 (11) |
C41 | 0.0281 (18) | 0.0193 (17) | 0.0284 (18) | 0.0025 (14) | 0.0134 (15) | 0.0000 (13) |
C42 | 0.0178 (16) | 0.0291 (19) | 0.0342 (19) | 0.0051 (14) | 0.0097 (14) | 0.0091 (15) |
C43 | 0.0167 (15) | 0.0324 (18) | 0.0283 (17) | −0.0045 (14) | 0.0034 (13) | 0.0076 (15) |
C44 | 0.0190 (16) | 0.0237 (17) | 0.0195 (15) | −0.0051 (13) | 0.0025 (12) | 0.0009 (13) |
C45 | 0.030 (2) | 0.043 (3) | 0.056 (3) | 0.0023 (19) | 0.006 (2) | −0.003 (2) |
C46 | 0.036 (2) | 0.048 (3) | 0.054 (3) | 0.010 (2) | −0.007 (2) | −0.002 (2) |
C47 | 0.046 (3) | 0.043 (3) | 0.034 (2) | 0.003 (2) | 0.0074 (18) | −0.0024 (19) |
C48 | 0.037 (3) | 0.092 (5) | 0.088 (5) | 0.011 (3) | 0.001 (3) | −0.031 (4) |
Cl1 | 0.0199 (4) | 0.0220 (4) | 0.0371 (5) | −0.0016 (3) | −0.0112 (3) | 0.0027 (3) |
Cl2 | 0.0344 (4) | 0.0152 (3) | 0.0128 (3) | 0.0019 (3) | 0.0008 (3) | 0.0034 (3) |
N1 | 0.091 (5) | 0.086 (4) | 0.066 (4) | 0.013 (3) | 0.019 (3) | −0.001 (3) |
N2 | 0.071 (3) | 0.069 (3) | 0.054 (3) | 0.029 (3) | 0.013 (2) | 0.001 (2) |
P1 | 0.0128 (3) | 0.0113 (3) | 0.0118 (3) | −0.0015 (3) | 0.0020 (3) | −0.0003 (3) |
P2 | 0.0151 (4) | 0.0104 (3) | 0.0114 (3) | −0.0009 (3) | 0.0024 (3) | 0.0009 (3) |
Pt1 | 0.01585 (5) | 0.01254 (5) | 0.01380 (5) | 0.00102 (5) | 0.00066 (4) | 0.00026 (4) |
C51 | 0.144 (6) | 0.130 (7) | 0.170 (8) | −0.018 (5) | 0.072 (4) | −0.085 (6) |
C52 | 0.142 (6) | 0.128 (7) | 0.168 (8) | −0.018 (5) | 0.071 (5) | −0.086 (6) |
N3 | 0.145 (6) | 0.130 (7) | 0.170 (8) | −0.016 (5) | 0.068 (4) | −0.085 (6) |
C1—C2 | 1.398 (5) | C27—C32 | 1.423 (4) |
C1—C6 | 1.397 (5) | C28—H28 | 0.9500 |
C1—P1 | 1.805 (3) | C28—C29 | 1.366 (5) |
C2—H2 | 0.9500 | C29—H29 | 0.9500 |
C2—C3 | 1.387 (5) | C29—C30 | 1.410 (5) |
C3—H3 | 0.9500 | C30—H30 | 0.9500 |
C3—C4 | 1.374 (6) | C30—C31 | 1.368 (4) |
C4—H4 | 0.9500 | C31—H31 | 0.9500 |
C4—C5 | 1.376 (7) | C31—C32 | 1.421 (4) |
C5—H5 | 0.9500 | C33—C34 | 1.395 (5) |
C5—C6 | 1.398 (5) | C33—C38 | 1.391 (5) |
C6—H6 | 0.9500 | C33—P2 | 1.824 (3) |
C7—C8 | 1.389 (5) | C34—H34 | 0.9500 |
C7—C12 | 1.395 (4) | C34—C35 | 1.386 (5) |
C7—P1 | 1.825 (3) | C35—H35 | 0.9500 |
C8—H8 | 0.9500 | C35—C36 | 1.383 (6) |
C8—C9 | 1.399 (5) | C36—H36 | 0.9500 |
C9—H9 | 0.9500 | C36—C37 | 1.375 (6) |
C9—C10 | 1.381 (5) | C37—H37 | 0.9500 |
C10—H10 | 0.9500 | C37—C38 | 1.394 (5) |
C10—C11 | 1.387 (5) | C38—H38 | 0.9500 |
C11—H11 | 0.9500 | C39—C40 | 1.397 (4) |
C11—C12 | 1.383 (5) | C39—C44 | 1.399 (4) |
C12—H12 | 0.9500 | C39—P2 | 1.803 (3) |
C13—C14 | 1.421 (4) | C40—H40 | 0.9500 |
C13—C22 | 1.390 (4) | C40—C41 | 1.387 (5) |
C13—P1 | 1.833 (3) | C41—H41 | 0.9500 |
C14—H14 | 0.9500 | C41—C42 | 1.379 (5) |
C14—C15 | 1.363 (4) | C42—H42 | 0.9500 |
C15—H15 | 0.9500 | C42—C43 | 1.390 (6) |
C15—C16 | 1.413 (4) | C43—H43 | 0.9500 |
C16—C17 | 1.416 (4) | C43—C44 | 1.385 (5) |
C16—C21 | 1.418 (4) | C44—H44 | 0.9500 |
C17—H17 | 0.9500 | C45—C46 | 1.438 (7) |
C17—C18 | 1.369 (5) | C45—N1 | 1.134 (7) |
C18—H18 | 0.9500 | C46—H46A | 0.9800 |
C18—C19 | 1.411 (5) | C46—H46B | 0.9800 |
C19—H19 | 0.9500 | C46—H46C | 0.9800 |
C19—C20 | 1.369 (5) | C47—C48 | 1.437 (7) |
C20—H20 | 0.9500 | C47—N2 | 1.123 (6) |
C20—C21 | 1.419 (4) | C48—H48A | 0.9800 |
C21—C22 | 1.434 (4) | C48—H48B | 0.9800 |
C22—C23 | 1.497 (4) | C48—H48C | 0.9800 |
C23—C24 | 1.389 (4) | Pt1—Cl1 | 2.3518 (8) |
C23—C32 | 1.439 (4) | Pt1—Cl2 | 2.3536 (8) |
C24—C25 | 1.420 (4) | P1—Pt1 | 2.2447 (8) |
C24—P2 | 1.835 (3) | P2—Pt1 | 2.2422 (8) |
C25—H25 | 0.9500 | C51—H51A | 0.9800 |
C25—C26 | 1.362 (4) | C51—H51B | 0.9800 |
C26—H26 | 0.9500 | C51—H51C | 0.9800 |
C26—C27 | 1.408 (4) | C51—C52 | 1.426 (17) |
C27—C28 | 1.417 (4) | C52—N3 | 1.023 (15) |
C2—C1—P1 | 120.3 (3) | C30—C29—H29 | 120.3 |
C6—C1—C2 | 119.7 (3) | C29—C30—H30 | 119.5 |
C6—C1—P1 | 120.0 (3) | C31—C30—C29 | 121.0 (3) |
C1—C2—H2 | 120.0 | C31—C30—H30 | 119.5 |
C3—C2—C1 | 120.1 (4) | C30—C31—H31 | 119.4 |
C3—C2—H2 | 120.0 | C30—C31—C32 | 121.1 (3) |
C2—C3—H3 | 120.0 | C32—C31—H31 | 119.4 |
C4—C3—C2 | 119.9 (4) | C27—C32—C23 | 119.6 (3) |
C4—C3—H3 | 120.0 | C31—C32—C23 | 122.8 (3) |
C3—C4—H4 | 119.6 | C31—C32—C27 | 117.6 (3) |
C3—C4—C5 | 120.8 (3) | C34—C33—P2 | 118.2 (2) |
C5—C4—H4 | 119.6 | C38—C33—C34 | 118.8 (3) |
C4—C5—H5 | 119.8 | C38—C33—P2 | 122.9 (3) |
C4—C5—C6 | 120.4 (4) | C33—C34—H34 | 119.6 |
C6—C5—H5 | 119.8 | C35—C34—C33 | 120.8 (3) |
C1—C6—C5 | 119.1 (4) | C35—C34—H34 | 119.6 |
C1—C6—H6 | 120.4 | C34—C35—H35 | 120.1 |
C5—C6—H6 | 120.4 | C36—C35—C34 | 119.7 (4) |
C8—C7—C12 | 119.2 (3) | C36—C35—H35 | 120.1 |
C8—C7—P1 | 121.9 (3) | C35—C36—H36 | 119.9 |
C12—C7—P1 | 118.8 (2) | C37—C36—C35 | 120.2 (3) |
C7—C8—H8 | 120.2 | C37—C36—H36 | 119.9 |
C7—C8—C9 | 119.7 (3) | C36—C37—H37 | 119.9 |
C9—C8—H8 | 120.2 | C36—C37—C38 | 120.2 (4) |
C8—C9—H9 | 119.7 | C38—C37—H37 | 119.9 |
C10—C9—C8 | 120.6 (3) | C33—C38—C37 | 120.2 (4) |
C10—C9—H9 | 119.7 | C33—C38—H38 | 119.9 |
C9—C10—H10 | 120.1 | C37—C38—H38 | 119.9 |
C9—C10—C11 | 119.7 (3) | C40—C39—C44 | 119.3 (3) |
C11—C10—H10 | 120.1 | C40—C39—P2 | 119.6 (2) |
C10—C11—H11 | 120.0 | C44—C39—P2 | 121.1 (2) |
C12—C11—C10 | 119.9 (3) | C39—C40—H40 | 120.0 |
C12—C11—H11 | 120.0 | C41—C40—C39 | 120.0 (3) |
C7—C12—H12 | 119.6 | C41—C40—H40 | 120.0 |
C11—C12—C7 | 120.8 (3) | C40—C41—H41 | 119.8 |
C11—C12—H12 | 119.6 | C42—C41—C40 | 120.5 (3) |
C14—C13—P1 | 118.9 (2) | C42—C41—H41 | 119.8 |
C22—C13—C14 | 119.1 (3) | C41—C42—H42 | 120.0 |
C22—C13—P1 | 121.7 (2) | C41—C42—C43 | 120.1 (3) |
C13—C14—H14 | 119.3 | C43—C42—H42 | 120.0 |
C15—C14—C13 | 121.4 (3) | C42—C43—H43 | 120.0 |
C15—C14—H14 | 119.3 | C44—C43—C42 | 120.0 (3) |
C14—C15—H15 | 119.5 | C44—C43—H43 | 120.0 |
C14—C15—C16 | 121.0 (3) | C39—C44—H44 | 119.9 |
C16—C15—H15 | 119.5 | C43—C44—C39 | 120.2 (3) |
C15—C16—C17 | 121.3 (3) | C43—C44—H44 | 119.9 |
C15—C16—C21 | 118.8 (3) | N1—C45—C46 | 178.3 (6) |
C17—C16—C21 | 119.9 (3) | C45—C46—H46A | 109.5 |
C16—C17—H17 | 119.6 | C45—C46—H46B | 109.5 |
C18—C17—C16 | 120.7 (3) | C45—C46—H46C | 109.5 |
C18—C17—H17 | 119.6 | H46A—C46—H46B | 109.5 |
C17—C18—H18 | 120.3 | H46A—C46—H46C | 109.5 |
C17—C18—C19 | 119.5 (3) | H46B—C46—H46C | 109.5 |
C19—C18—H18 | 120.3 | N2—C47—C48 | 178.6 (6) |
C18—C19—H19 | 119.4 | C47—C48—H48A | 109.5 |
C20—C19—C18 | 121.2 (3) | C47—C48—H48B | 109.5 |
C20—C19—H19 | 119.4 | C47—C48—H48C | 109.5 |
C19—C20—H20 | 119.7 | H48A—C48—H48B | 109.5 |
C19—C20—C21 | 120.6 (3) | H48A—C48—H48C | 109.5 |
C21—C20—H20 | 119.7 | H48B—C48—H48C | 109.5 |
C16—C21—C20 | 118.2 (3) | C1—P1—C7 | 106.21 (15) |
C16—C21—C22 | 119.7 (3) | C1—P1—C13 | 105.57 (14) |
C20—C21—C22 | 122.1 (3) | C1—P1—Pt1 | 117.11 (12) |
C13—C22—C21 | 120.0 (3) | C7—P1—C13 | 104.64 (14) |
C13—C22—C23 | 121.4 (3) | C7—P1—Pt1 | 110.51 (10) |
C21—C22—C23 | 118.6 (3) | C13—P1—Pt1 | 111.90 (10) |
C24—C23—C22 | 121.2 (3) | C24—P2—Pt1 | 111.01 (10) |
C24—C23—C32 | 119.5 (3) | C33—P2—C24 | 104.08 (14) |
C32—C23—C22 | 119.3 (3) | C33—P2—Pt1 | 110.78 (11) |
C23—C24—C25 | 119.6 (3) | C39—P2—C24 | 106.24 (14) |
C23—C24—P2 | 121.6 (2) | C39—P2—C33 | 106.87 (15) |
C25—C24—P2 | 118.5 (2) | C39—P2—Pt1 | 116.96 (11) |
C24—C25—H25 | 119.4 | Cl1—Pt1—Cl2 | 87.44 (3) |
C26—C25—C24 | 121.3 (3) | P1—Pt1—Cl1 | 90.31 (3) |
C26—C25—H25 | 119.4 | P1—Pt1—Cl2 | 171.33 (3) |
C25—C26—H26 | 119.5 | P2—Pt1—Cl1 | 170.91 (3) |
C25—C26—C27 | 121.1 (3) | P2—Pt1—Cl2 | 90.62 (3) |
C27—C26—H26 | 119.5 | P2—Pt1—P1 | 92.87 (3) |
C26—C27—C28 | 121.4 (3) | H51A—C51—H51B | 109.5 |
C26—C27—C32 | 118.8 (3) | H51A—C51—H51C | 109.5 |
C28—C27—C32 | 119.8 (3) | H51B—C51—H51C | 109.5 |
C27—C28—H28 | 119.5 | C52—C51—H51A | 109.5 |
C29—C28—C27 | 121.0 (3) | C52—C51—H51B | 109.5 |
C29—C28—H28 | 119.5 | C52—C51—H51C | 109.5 |
C28—C29—H29 | 120.3 | N3—C52—C51 | 159.4 (19) |
C28—C29—C30 | 119.5 (3) | ||
C1—C2—C3—C4 | 0.5 (5) | C23—C24—P2—C33 | −163.2 (3) |
C2—C1—C6—C5 | 1.4 (5) | C23—C24—P2—C39 | −50.6 (3) |
C2—C1—P1—C7 | 66.5 (3) | C23—C24—P2—Pt1 | 77.5 (3) |
C2—C1—P1—C13 | −44.3 (3) | C24—C23—C32—C27 | 3.0 (4) |
C2—C1—P1—Pt1 | −169.6 (2) | C24—C23—C32—C31 | −178.7 (3) |
C2—C3—C4—C5 | 0.2 (6) | C24—C25—C26—C27 | 2.3 (5) |
C3—C4—C5—C6 | −0.1 (6) | C25—C24—P2—C33 | 23.5 (3) |
C4—C5—C6—C1 | −0.7 (5) | C25—C24—P2—C39 | 136.1 (2) |
C6—C1—C2—C3 | −1.3 (5) | C25—C24—P2—Pt1 | −95.7 (2) |
C6—C1—P1—C7 | −115.7 (3) | C25—C26—C27—C28 | 179.1 (3) |
C6—C1—P1—C13 | 133.5 (3) | C25—C26—C27—C32 | −0.5 (5) |
C6—C1—P1—Pt1 | 8.2 (3) | C26—C27—C28—C29 | −180.0 (3) |
C7—C8—C9—C10 | 0.6 (6) | C26—C27—C32—C23 | −2.2 (4) |
C8—C7—C12—C11 | −2.6 (5) | C26—C27—C32—C31 | 179.4 (3) |
C8—C7—P1—C1 | −2.9 (3) | C27—C28—C29—C30 | 0.5 (5) |
C8—C7—P1—C13 | 108.5 (3) | C28—C27—C32—C23 | 178.3 (3) |
C8—C7—P1—Pt1 | −130.9 (3) | C28—C27—C32—C31 | −0.1 (4) |
C8—C9—C10—C11 | −1.1 (6) | C28—C29—C30—C31 | −0.1 (5) |
C9—C10—C11—C12 | −0.2 (6) | C29—C30—C31—C32 | −0.4 (5) |
C10—C11—C12—C7 | 2.1 (5) | C30—C31—C32—C23 | −177.8 (3) |
C12—C7—C8—C9 | 1.2 (5) | C30—C31—C32—C27 | 0.5 (5) |
C12—C7—P1—C1 | 174.9 (3) | C32—C23—C24—C25 | −1.3 (4) |
C12—C7—P1—C13 | −73.7 (3) | C32—C23—C24—P2 | −174.5 (2) |
C12—C7—P1—Pt1 | 46.9 (3) | C32—C27—C28—C29 | −0.4 (5) |
C13—C14—C15—C16 | 1.3 (5) | C33—C34—C35—C36 | 1.6 (5) |
C13—C22—C23—C24 | −69.7 (4) | C34—C33—C38—C37 | 0.9 (5) |
C13—C22—C23—C32 | 109.7 (3) | C34—C33—P2—C24 | −75.0 (3) |
C14—C13—C22—C21 | −0.3 (4) | C34—C33—P2—C39 | 172.9 (2) |
C14—C13—C22—C23 | 178.8 (3) | C34—C33—P2—Pt1 | 44.4 (3) |
C14—C13—P1—C1 | 134.1 (2) | C34—C35—C36—C37 | −1.2 (6) |
C14—C13—P1—C7 | 22.2 (3) | C35—C36—C37—C38 | 0.6 (6) |
C14—C13—P1—Pt1 | −97.5 (2) | C36—C37—C38—C33 | −0.4 (6) |
C14—C15—C16—C17 | 180.0 (3) | C38—C33—C34—C35 | −1.5 (5) |
C14—C15—C16—C21 | −0.5 (5) | C38—C33—P2—C24 | 108.7 (3) |
C15—C16—C17—C18 | 179.2 (3) | C38—C33—P2—C39 | −3.5 (3) |
C15—C16—C21—C20 | −178.8 (3) | C38—C33—P2—Pt1 | −131.9 (3) |
C15—C16—C21—C22 | −0.7 (4) | C39—C40—C41—C42 | −0.4 (5) |
C16—C17—C18—C19 | −0.4 (5) | C40—C39—C44—C43 | 1.2 (5) |
C16—C21—C22—C13 | 1.0 (4) | C40—C39—P2—C24 | 129.9 (3) |
C16—C21—C22—C23 | −178.1 (3) | C40—C39—P2—C33 | −119.4 (3) |
C17—C16—C21—C20 | 0.7 (4) | C40—C39—P2—Pt1 | 5.4 (3) |
C17—C16—C21—C22 | 178.9 (3) | C40—C41—C42—C43 | −0.4 (5) |
C17—C18—C19—C20 | 0.6 (6) | C41—C42—C43—C44 | 1.6 (5) |
C18—C19—C20—C21 | −0.1 (5) | C42—C43—C44—C39 | −1.9 (5) |
C19—C20—C21—C16 | −0.6 (5) | C44—C39—C40—C41 | 0.0 (5) |
C19—C20—C21—C22 | −178.6 (3) | C44—C39—P2—C24 | −48.8 (3) |
C20—C21—C22—C13 | 179.1 (3) | C44—C39—P2—C33 | 61.9 (3) |
C20—C21—C22—C23 | 0.0 (4) | C44—C39—P2—Pt1 | −173.4 (2) |
C21—C16—C17—C18 | −0.3 (5) | P1—C1—C2—C3 | 176.5 (3) |
C21—C22—C23—C24 | 109.4 (3) | P1—C1—C6—C5 | −176.4 (3) |
C21—C22—C23—C32 | −71.3 (4) | P1—C7—C8—C9 | 179.0 (3) |
C22—C13—C14—C15 | −0.9 (4) | P1—C7—C12—C11 | 179.6 (3) |
C22—C13—P1—C1 | −52.6 (3) | P1—C13—C14—C15 | 172.6 (2) |
C22—C13—P1—C7 | −164.4 (2) | P1—C13—C22—C21 | −173.6 (2) |
C22—C13—P1—Pt1 | 75.9 (2) | P1—C13—C22—C23 | 5.5 (4) |
C22—C23—C24—C25 | 178.1 (3) | P2—C24—C25—C26 | 172.0 (3) |
C22—C23—C24—P2 | 4.9 (4) | P2—C33—C34—C35 | −178.0 (3) |
C22—C23—C32—C27 | −176.3 (3) | P2—C33—C38—C37 | 177.2 (3) |
C22—C23—C32—C31 | 2.0 (4) | P2—C39—C40—C41 | −178.8 (2) |
C23—C24—C25—C26 | −1.4 (5) | P2—C39—C44—C43 | 179.9 (3) |
Funding information
The following sources of funding are gratefully acknowledged: the Natural Sciences Engineering Research Council of Canada for a Discovery Grant to DEH (RGPIN-2014–03733) and a USRA to GU; the Canadian Foundation for Innovation and Research Manitoba for an award in support of an X-ray diffractometer (CFI No. 32146); the University of Manitoba for a UMGF PhD Fellowship (JDB).
References
Birkholz (née Gensow), M., Freixa, Z. & van Leeuwen, P. W. N. M. (2009). Chem. Soc. Rev. 38, 1099–1118. Google Scholar
Bombard, S., Gariboldi, M. B., Monti, E., Gabano, E., Gaviglio, L., Ravera, M. & Osella, D. (2010). J. Biol. Inorg. Chem. 15, 841–850. Web of Science CrossRef CAS PubMed Google Scholar
Bruker (2016). APEX3, SADABS and SAINT. Madison, Wisconsin, USA. Google Scholar
Doherty, S., Knight, J. G., Smyth, C. H., Harrington, R. W. & Clegg, W. (2006). J. Org. Chem. 71, 9751–9764. Web of Science CSD CrossRef PubMed CAS Google Scholar
Dolomanov, O. V., Bourhis, L. J., Gildea, R. J., Howard, J. A. K. & Puschmann, H. (2009). J. Appl. Cryst. 42, 339–341. Web of Science CrossRef CAS IUCr Journals Google Scholar
Genet, J.-P., Ayad, T. & Ratovelomanana-Vidal, V. (2014). Chem. Rev. 114, 2824–2880. Web of Science CrossRef CAS PubMed Google Scholar
Guerrero-Ríos, I. & Martin, E. (2014). Dalton Trans. 43, 7533–7539. Web of Science PubMed Google Scholar
Iwata, T., Miyake, Y., Nishibayashi, Y. & Uemura, S. (2002). J. Chem. Soc. Perkin Trans. 1, pp. 1548–1554. Web of Science CrossRef Google Scholar
Mandapati, P., Braun, J. D., Killeen, C., Davis, R. L., Williams, J. A. G. & Herbert, D. E. (2019). Inorg. Chem. 58, 14808–14817. Web of Science CSD CrossRef CAS PubMed Google Scholar
Misra, A., Dwivedi, J. & Kishore, D. (2017). Synth. Commun. 47, 497–535. Web of Science CrossRef CAS Google Scholar
Miyashita, A., Yasuda, A., Takaya, H., Toriumi, K., Ito, T., Souchi, T. & Noyori, R. (1980). J. Am. Chem. Soc. 102, 7932–7934. CSD CrossRef CAS Web of Science Google Scholar
Noyori, R. (1994). Asymmetric Catalysis in Organic Synthesis. New York: Wiley. Google Scholar
Pereira, M. M., Calvete, M. J. F., Carrilho, R. M. B. & Abreu, A. R. (2013). Chem. Soc. Rev. 42, 6990–7027. Web of Science CrossRef CAS PubMed 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
Spek, A. L. (2020). Acta Cryst. E76, 1–11. Web of Science CrossRef IUCr Journals Google Scholar
Strukul, G., Varagnolo, A. & Pinna, F. (1997). J. Mol. Catal. A Chem. 117, 413–423. CrossRef CAS Web of Science Google Scholar
Véron, A. C., Felber, M., Blacque, O. & Spingler, B. (2013). Polyhedron, 52, 102–105. Google Scholar
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