Synthesis, Characterization, and Crystal Structure of a Triazine Anion Pentaﬂuoroosmium(VI) Complex

crystals

Article Synthesis, Characterization, and Crystal Structure of a Triazine Anion Pentaﬂuoroosmium(VI) Complex

Monther A. Khanfar 1,* ID , Basem F. Ali 2,3 ID , Hashem Shorafa 4 and Konrad Seppelt 4 1 Department of Chemistry, The University of Jordan, Amman 11942, Jordan 2 Department of Chemistry, King Faisal University, Al-Ahssa, Hufof 31982, Saudi Arabia; [email protected] or [email protected] 3 Department of Chemistry, Al al-Bayt University, Mafraq 25113, Jordan 4 Institut für Chemie und Biochemie, Freie Universität Berlin, Fabeckstraße 34/36, 14195 Berlin, Germany; [email protected] (H.S.); [email protected] (K.S.) * Correspondence: [email protected]; Tel.: +962-6-5355-000

Received: 11 December 2017; Accepted: 23 January 2018; Published: 29 January 2018

Abstract: The synthesis and characterization of a novel triazine anion pentafluoroosmium(VI) complex are presented. The single crystal determination of the title compound (hereafter denoted 1) ◦ was carried out at −140 C. Compound 1,C3F4N3OsF5, crystallizes in the monoclinic space group, ◦ P21/n, with unit cell dimensions: a = 8.6809(17) Å, b = 7.6848(15) Å, c = 12.415(3) Å, β = 102.633(4) , V = 808.2(3) Å3, and Z = 4. Synthesis, characterization, X-ray diffraction study along with the crystal supramolecular analysis of the title complex were carried out. The complex contains the − anionic triazine unit C3N3F4 acting as a mono dentate ligand to osmium(VI) with five fluoro ligands in a slightly distorted octahedral geometry around osmium(VI) ion (osmium is denoted − as Os). The C3N3F4 , triazine anion ring deviates from planarity, only with the C1 being tetrahedral. The crystal lattice of the title compound displays significant intermolecular X···X interactions, namly F···F, F···N and F···C. All types of X···X bonding consolidate to form a three-dimensional network.

Keywords: triazine anion; crystal structure; ﬂuoroosmium(VI) complexes; supramolecular crystal; F···F; F···N; F···C intermolecular interactions

1. Introduction

The employment of osmium(VI) fluoride/antimony(V) fluoride (OsF6/SbF5) as a powerful oxidizing agent to break the aromaticity of benzene to form radical benzene cations was established some time ago [1]. This distorted radical cation was characterized using X-ray structural analysis [1]. However, the isolation of the benzene radical cation is a challenge. Seppelt and co-workers obtained + − + − the compoundsC6F6 Os2F11 and C6F6 Sb2F11 [1,2]. The synthesis and crystal structure of other substituted benzene cations such as aniline radical cation [3] and radical cation of monocyclic arenes [4,5] have also been reported. Further research was directed toward the formation of stable radicals for several organic systems [6–9]. On the other hand, fluorine-containing compounds are important for life and material sciences [10–12]. Fluorine is comparable to hydrogen atom in size but, possesses different physical and chemical properties, and capable of forming strong halogen bonds [13–19]. The latter can be of different motifs, such as F···F, F···N, and F···C intermolecular interactions. In an attempt to use other aromatic species in a manner similar to benzene, we encountered the 2,4,6-trifluoro-1,3,5-triazene ligand (Figure1). It was expected that this system would proceed easily to form a radical cation compared to benzene, but a pentafluoroosmium(VI)-complex containing − C3N3F4 ligand was detected instead. In this report, we are disclosing the successful synthesis, single crystal X-ray diffraction and crystal supramolecularity of this system.

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Figure 1. The chemical structure of 2,4,6-trifluoro-1,3,5-triazene ligand. Figure 1. The chemical structure of 2,4,6-trifluoro-1,3,5-triazene ligand. 2. Materials and Methods 2. Materials and Methods The compound is unstable at room temperature and sensitive to moisture. Therefore, IR and UV Thespectra compound could not is unstable be recorded. at room Raman temperature spectra and showed sensitive strong to moisture. fluorescence Therefore, in all IRcases. and Yield UV spectracould only could be not estimated be recorded. by the Raman amount spectra of colored showed crystalline strong material, fluorescence often in in all mixtures cases. Yield of colorless could onlycrystals, be estimated which were by the possibly amount a ofstarting colored material. crystalline material, often in mixtures of colorless crystals, which were possibly a starting material. Caution: Handling SbF5 and OsF6 requires eye and skin protection. Caution: Handling SbF and OsF requires eye and skin protection. The following reagents5 were purchased6 from the indicated vendor: C3N3F3 (Sigma-Aldrich The following reagents were purchased from the indicated vendor: C N F (Sigma-Aldrich Chemie GmbH), SbF5 (Fluorochem Ltd.), NH4F (E. Merck), CF3COOH (Merck3 3 3 Schuchardt). The Chemietriazine GmbH), was checked SbF5 (Fluorochem by NMR Ltd.),spectroscopy NH4F (E. for Merck), purity. CF3 COOHThe solvent (Merck sulfuryl Schuchardt). fluoride The triazinechloride was checked by NMR spectroscopy for purity. The solvent sulfuryl fluoride chloride (SO ClF) was (SO2ClF) was prepared by treating a mixture of thionyl chloride (SO2Cl2) and ammonium2 fluoride prepared by treating a mixture of thionyl chloride (SO Cl ) and ammonium fluoride (NH F) with (NH4F) with trifluoroacetic acid (CF3COOH) [20]. SbF2 5 was2 vacuum distilled twice using4 a glass trifluoroaceticvacuum line acidwith (CF a −330COOH) °C trap. [20 ].The SbF resulting5 was vacuum liquid distilled was clea twicer, colorless, using a and glass highly vacuum viscous. line with The a −30 ◦C trap. The resulting liquid was clear, colorless, and highly viscous. The compound OsF compound OsF6 was obtained via a reaction of Os powder and F2 in Monel autoclaves at 300 °C [21].6 ◦ wasReagents obtained and via starting a reaction materials of Os must powder be highly and F2 purein Monel since autoclavescontaminants at 300are oxidizedC[21]. Reagents preferentially. and startingReactions materials were performed must be highly in PFA pure (Poly since perfluorov contaminantsinylether are oxidized tetrafluoroethylene preferentially. copolymer) Reactions weretubes; performed in PFA (Poly perfluorovinylether tetrafluoroethylene copolymer) tubes; volatile materials volatile materials (anhydrous SO2ClF, OsF6) were handled in a stainless-steel vacuum line. (anhydrous SO ClF, OsF ) were handled in a stainless-steel vacuum line. OsF6 (1002 mg) and6 SO2ClF (2 mL) were condensed in a PFA tube containing SbF5 (50 mg). The mixtureOsF6 was(100 allowed mg) and to SO warm2ClF to (2 0 mL) °C to were ensure condensed a homogenous in a PFA mixture. tube containing The mixture SbF was5 (50 cooled mg). The mixture was allowed to warm to 0 ◦C to ensure a homogenous mixture. The mixture was again with the aid of liquid nitrogen. C3N3F3 (100 mg) was condensed into the cooled mixture. The cooledmixture again was with then the allowed aid of liquidto warm nitrogen. very slowly C3N3F to3 (100 −30 mg)°C, a wasffording condensed a yellow into clear the cooledsolution. mixture. At −30 The mixture was then allowed to warm very slowly to −30 ◦C, affording a yellow clear solution. °C, the excess C3N3F3 and other volatiles were removed under vacuum. After that, SO2ClF (2 mL) ◦ Atwas−30 condensedC, the excess in a PFA C3N tube.3F3 and Recrystallization other volatiles from were − removed30 °C to − under78 °C a vacuum.fforded yellow After that,crystals. SO2 ClFCare ◦ ◦ (2must mL) be was taken condensed to ensure in that a PFA the temperature tube. Recrystallization never exceeds from −30− °C30 throughoutC to −78 theC affordedentire procedure. yellow ◦ crystals.Single Care crystal must befor taken X-ray to diffraction ensure that was the temperatureperformed on never a Bruker-AXS, exceeds −30 D8C throughoutventure, photon the entiredetector, procedure. tube: incotec microfokus (Mo Kα radiation, Bruker, Germany) under oxygen- and moisture-freeSingle crystal conditions for X-ray at diffraction temperatures was performedbelow −100 on °C a using Bruker-AXS, a special D8 device venture, of photonlocal design detector, [22]. tube:All data incotec collections microfokus were (Mo performed Kα radiation, at −140 Bruker, °C. After Germany) semiempirical under oxygen- absorption and corrections, moisture-free the ◦ conditionsstructure atwas temperatures solved by belowdirect −methods100 C usingand refined a special using device the of program local design SHELXTL [22]. All [23,24]. data ◦ collectionsNon-hydrogen were performedatoms were at −refined140 C. anisotropically; After semiempirical H atoms absorption were re corrections,fined isotropically. the structure Relevant was solveddata collection by direct methodsand refinement and refined parameters using the are program listed in SHELXTL Table 1. [23,24]. Non-hydrogen atoms were refinedCrystallographic anisotropically; data H atoms in cif were format refined have isotropically. been deposited Relevant with the data Cambridge collection andCrystallographic refinement parametersData Center are (CCDC listed in1508189). Table1. Copies of the data can be obtained free of charge from The Director, CCDC,Crystallographic 12 Union dataRoad, in cifCambridge, format have beenCB2 deposited1EZ, UK, with fax: the Cambridge+44 1223 Crystallographic366033, email: [email protected] Center (CCDC 1508189). or on Copiesthe web of at the http://www.ccdc.cam.ac.uk. data can be obtained free of charge from The Director, CCDC, 12 Union Road, Cambridge, CB2 1EZ, UK, fax: +44 1223 366033, email: [email protected] or on the web at http://www.ccdc.cam.ac.uk.

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Table 1. X-ray structure experimental details.

Crystals 2018, 8CCDC, 63 Deposition Number 1508189 3 of 9 Empirical formula; formula weight C3F4N3OsF5; 439.26 TemperatureTable (K) 1. X-ray structure experimental details. 133(2) λ (Å) 0.71073 CrystalCCDC system; Deposition space Numbergroup 1508189 Monoclinic; P21/n

Empirical formula; formula weight C3F4N3OsFa =5 8.6809(17); 439.26 Å Temperature (K) 133(2)b = 7.6848(15) Å Unit cell dimensions λ (Å) 0.71073c = 12.415(3) Å Crystal system; space group Monoclinic;β = P2102.633(4)°1/n a = 8.6809(17) Å 3 V (Å ) b = 7.6848(15)808.2(3) Å Unit cell dimensions Z c = 12.415(3) Å4 ◦ Dcalc. (Mg/m3) β = 102.633(4)3.610 3 Absorption coefficientV (Å ) (mm−1) 808.2(3) 15.93 F(000)Z 4 781 D (Mg/m3) 3.610 calc. 3 AbsorptionCrystal size coefficient (mm )(mm −1) 15.93 0.2 × 0.1 × 0.1 Theta range forF data(000) collection 781 2.6° to 30.6° LimitingCrystal sizeindices (mm 3) −11 0.2≤h ×≤ 12,0.1 −×80.1 ≤ k ≤ 10, −17 ≤ l ≤ 17 ◦ ◦ ThetaReflections range for collected data collection 2.6 to 30.6 12782 Limiting indices −11 ≤ h ≤ 12, −8 ≤ k ≤ 10, −17 ≤ l ≤ 17 Completeness to theta = 25.125° 99.8% Reflections collected 12782 CompletenessIndependent toreflections theta = 25.125 ◦ 247499.8% (R(int) = 0.023) ObservedIndependent reflections reflections 2474 (R(int) 2140 = 0.023) (II > 2(I)) ReflectionsObserved used for reflections refinement 2140 (II > 2(I)) 2474 ReflectionsRefinement used method for refinement Full-matrix 2474 least-squares on F2 Refinement method Full-matrix least-squares on F2 Data/restraints/parametersData/restraints/parameters 2474/0/1452474/0/145 Goodness-of-fitGoodness-of-fit on on F2F 2 1.052 1.052 R valuesR values (I > (I 2sigma(I)) > 2sigma(I)) R1 = 0.0152, R1 = 0.0152, wR2 =0.0356 wR2 = 0.0356 R valuesR values (all (all data) data) R1 = 0.0199, R1 = 0.0199, wR2 =0.0374 wR2 = 0.0374 − · −3 LargestLargest difference difference electron electron densities densities 1.01 and 1.011.01 and e Å−1.01 e·Å−3

3. Results and Discussion

3.1. Synthesis of 1 The complex 1 was prepared as outlinedoutlined in SchemeScheme1 .1. The The proposed proposed complex complex formation formation mechanism involves the addition of a ﬂuoride ion to a carbon center of C N F , forming a C N F − mechanism involves the addition of a fluoride ion to a carbon center of 3C33N33F3, forming a 3C3N3 3F4 4− anion, which in turn acts as a mono-dentatemono-dentate ligandligand toto thethe metalmetal center.center.

Scheme 1. Proposed stepwise formation of 1..

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TheThe formation formation of of the the triazine triazine anion anion was was reported reported previously previously (Scheme (Scheme2) from 2) from the reaction the reaction of CsF of 3 3 3 andCsF C and3N3 FC3 NwithoutF without a sufﬁcient a sufficient characterization characterization [25]. [25]. Kingston Kingston et al. et [ 26al.] [26] reported reported the synthesisthe synthesis of theof samethe same anion anion using using a different a different strategy, strategy, and theand product the product was characterizedwas characterized spectroscopically spectroscopically and and by X-rayby X-ray structural structural analysis. analysis. Therefore, Therefore, our our method method represents represents a newa new strategy strategy for for the the formation formation of of this this anionanion which which forms forms thethe foundationfoundation for the synt synthesishesis of of other other anionic anionic triazine triazine species. species.

Scheme 2. Reported methods for the preparation of C3N3F−4−. Reaction 1, Reference [25]; reaction 2, Scheme 2. Reported methods for the preparation of C3N3F4 . Reaction 1, Reference [25]; reaction 2, Reference [26]. Reference [26].

3.2. Molecular Structure 3.2. Molecular Structure The asymmetric unit in 1 contains one independent complex (Figure 2). The molecular complex The asymmetric unit in 1 contains one independent complex (Figure2). The molecular complex has octahedral geometry around an osmium atom. The unique M–F distances are 1.8638(17)– has octahedral geometry around an osmium atom. The unique M–F distances are 1.8638(17)–1.8696(17) 1.8696(17) Å, while the linear and perpendicular F–Os–F angles are in the ranges of 179.25(8)– Å, while the linear and perpendicular F–Os–F angles are in the ranges of 179.25(8)–178.68(7) and 178.68(7) and 87.78(8)–91.55(8)° (Table 2). These bond distances and angles are within the reported 87.78(8)–91.55(8)◦ (Table2). These bond distances and angles are within the reported values of values of M–F-containing compounds [2,27,28]. The C3/N3 part of the C3N3F4− ring is planar, only M–F-containing compounds [2,27,28]. The C3/N3 part of the C N F − ring is planar, only with the C1 with the C1 atom being tetrahedral. The C–N distances in3 3the4 ranges of 1.305(4)–1.320(4) and atom being tetrahedral. The C–N distances in the ranges of 1.305(4)–1.320(4) and 1.445(4)–1.422(4) are 1.445(4)–1.422(4) are consistent with the bonds between double C=N and single C–N bonds, consistent with the bonds between double C=N and single C–N bonds, indicating a delocalization indicating a delocalization of charge in the ring consistent with the anion geometry. This is best of charge in the ring consistent with the anion geometry. This is best described by the resonance described by the resonance shown in Figure 3. These C–N bond distances and angles are slightly shown in Figure3. These C–N bond distances and angles are slightly different compared to those of different compared to those of the free anionic C3N3F4− [26]. The difference in some distances of C–N the free anionic C N F − [26]. The difference in some distances of C–N and C–F bonds, shown in and C–F bonds, shown3 3 4 in Table 2, might be attributed to the fact that the reported anion [26] is a free Table2, might be attributed to the fact that the reported anion [ 26] is a free anion crystallized with anion crystallized with another counter cation which allows the complete delocalization of the another counter cation which allows the complete delocalization of the charge over the anion, while the charge over the anion, while the anion in the title compound is bonded through one N atom with anion in the title compound is bonded through one N atom with Os(VI) and consequently affects Os(VI) and consequently affects the delocalization of the charge over the anion. This is also evident the delocalization of the charge over the anion. This is also evident by the different planarity of the by the different planarity of the reported anion C3N3F4− ring as compared to the bonded one (this reported anion C N F − ring as compared to the bonded one (this work). The C–F bond distances work). The C–F 3bond3 4 distances are different depending on the center to which they bonded. Those are different depending on the center to which they bonded. Those bonded to the tetrahedral C1 are bonded to the tetrahedral C1 are longer than those bonded to the planar sp2 carbons (C2 and C3; longer than those bonded to the planar sp2 carbons (C2 and C3; Table2). This fact makes this anion Table 2). This fact makes this anion susceptible to selective substitution (weak C1–F bonds), and this susceptible to selective substitution (weak C1–F bonds), and this has been used to synthesize the has been used to synthesize the substituted triazine anions [26]. substituted triazine anions [26].

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FigureFigure 2. 2.Molecular Molecular geometry geometry of of complex complex1 1with with atom atom labeling labeling scheme. scheme. Atoms Atoms drawn drawn at at the the 50% 50% Figure 2. Molecular geometry of complex 1 with atom labeling scheme. Atoms drawn at the 50% probabilityprobability level. level. probability level.

Figure 3. Charge delocalization in C3N3F−4− anion. FigureFigure 3. 3.Charge Charge delocalization delocalization in in C C3N3N3F3F44− anion.anion.

Table 2. Selected bond lengths (Å), bond and angles◦ (°) in 1. TableTable 2.2. SelectedSelected bondbond lengthslengths (Å),(Å), bondbond andand anglesangles( (°)) inin 1.1.

a average Bond Distances Os–F Complexa a Os–F Complex BondBond Distances Distances Os–FOs–F Complex Complex Os–FaverageOs–FaverageComplex Complex 1.8696(17)1.8696(17) 1.8696(17)1.8661(17) 1.8661(17)1.8661(17) Os–F 1.8638(17) b 1.825 bc; 1.857 c Os–FOs–F 1.8638(17)1.8638(17) 1.825 1.825; 1.857 b; 1.857 c 1.86871.86871.8687 (17) (17) (17) 1.8686(17)1.8686(17) 1.8686(17)a Os–N3Os–N3 2.078(2)2.078(2) a Os–N3 2.078(2)− a a − d C3N3F4 anion C3N3F4 anion C3N3F4− anion a C3N3F4− anion d C1–F1C3N 1.332(3)3F4− anion a 1.400(4)C3N3F4− anion d C1–F1C1–F1C1–F2 1.351(3)1.332(3)1.332(3) 1.383(4) 1.400(4) 1.400(4) C1–F2C1–F2C1–N1 1.422(4)1.351(3)1.351(3) 1.403(4) 1.383(4) 1.383(4) C1–N3 1.445(4) 1.400(4) C1–N1C1–N1 1.422(4)1.422(4) 1.403(4) 1.403(4) C1–N3N1–C2 1.316(4)1.445(4) 1.277(4) 1.400(4) C1–N3N2–C3 1.319(4)1.445(4) 1.319(4) 1.400(4) N1–C2N1–C2N3–C3 1.320(4)1.316(4)1.316(4) 1.279(4) 1.277(4) 1.277(4) N2–C3N2–C3C2–N2 1.305(4)1.319(4)1.319(4) 1.329(4) 1.319(4) 1.319(4) C2–F3 1.297(3) 1.345(3) N3–C3N3–C3 1.320(4)1.320(4) 1.279(4) 1.279(4) C2–N2C3–F4 1.298(3)1.305(4) 1.348(3) 1.329(4) C2–N2N1–C1–N3 112.8(2)1.305(4) 120.4(3) 1.329(4) C2–F3 1.297(3) 1.345(3) C2–F3N1–C2–N2 126.7(3)1.297(3) 132.0(3) 1.345(3) C3–F4C3–F4F4–C3–N2 115.3(2)1.298(3)1.298(3) 113.3(3) 1.348(3) 1.348(3) N1–C1–N3N1–C1–N3N2–C3–N3 128.9(3)112.8(2)112.8(2) 132.2(3) 120.4(3) 120.4(3) F4–C3–N3 115.8(2) 114.4(3) N1–C2–N2N1–C2–N2 126.7(3)126.7(3) 132.0(3) 132.0(3) F4–C3–N2F1–C1–F2 105.3(2)115.3(2) 101.1(2) 113.3(3) F4–C3–N2a This study; b from Reference [27115.3(2)]; c from Reference [2]; d from Reference 113.3(3) [26 ]. N2–C3–N3N2–C3–N3 128.9(3)128.9(3) 132.2(3) 132.2(3) F4–C3–N3 115.8(2) 114.4(3) 3.3. Crystal PackingF4–C3–N3 115.8(2) 114.4(3) F1–C1–F2F1–C1–F2 105.3(2)105.3(2) 101.1(2) 101.1(2) The crystal packinga This study; involves b from extensive Reference halogen [27]; c from···halogen Reference interactions. [2]; d from Reference These interactions [26]. assemble a This study; b from Reference [27]; c from Reference [2]; d from Reference [26]. the molecular complexes into a supramolecular three-dimensional lattice [29], as shown in Figure4, ··· ··· ··· ··· ··· via3.3.3.3. F Crystal CrystalF, F Packing N,Packing and F C intermolecular interactions (Table3). The F F (Figure5a), F N (Figure5b), and F···C (Figure5c) interactions are in the ranges of 2.834–2.887, 2.771–2.970, and 2.770–2.771 Å, The crystal packing involves extensive halogen···halogen interactions. These interactions respectively.The crystal packing involves extensive halogen···halogen interactions. These interactions assembleassemble the the molecular molecular complexes complexes into into a a supramolec supramolecularular three-dimensional three-dimensional lattice lattice [29], [29], as as shown shown in in FigureFigure 4, 4, via via F···F, F···F, F···N, F···N, and and F···C F···C intermolecular intermolecular interactions interactions (Table (Table 3). 3). The The F···F F···F (Figure (Figure 5a), 5a), F···N F···N

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(Figure 5b), and F···C (Figure 5c) interactions are in the ranges of 2.834–2.887, 2.771–2.970, and 2.770– Crystals2.771 Å, 2018 respectively., 8, x FOR PEER REVIEW 6 of 8

(Figure 5b), and F···C (Figure 5c) interactions are in the ranges of 2.834–2.887, 2.771–2.970, and 2.770– Crystals 2018, 8, 63 6 of 9 2.771 Å, respectively.

Figure 4. F···F, F···N, and F···C interactions (depicted as dotted and dashed lines) assemble the molecular complexes into a supramolecular three-dimensional network.

FigureFigure 4. F···F,F···F, F···N, F···N, and and F···C F···TableC interactions interactions 3. Halogen (depicte (depicted bond dgeometry as as dotted dotted (Å, and and°). dashed dashed lines) lines) assemble the molecular complexes into a supramolecular three-dimensional network. molecular complexesF···F into interactions a supramolecular three-dimensionalF···F network. –F···X– C1–F1···F3iTable–C2 i 3. Halogen bond geometry2.834 (Å, °). 87, 114 Table 3. Halogen bond geometry (Å, ◦). Os–F1···F9ii—C1 ii 2.840 88, 106 F···F interactions F···F –F···X– Os–F9···F2F··· iiiF–C1 interactions iii F··· F2.873 –F ···X– 143, 102 C1–F1···F3i–C2 i 2.834 87, 114 Os–F8···F9C1–F1iv–Os··· F3iv i–C2 i 2.834 2.887 87, 114 130, 137 Os–F1···F9ii—C1 ii 2.840 88, 106 F···N interactionsOs–F1···F9ii —C1 ii 2.840F···N 88, 106 –F···N iii iii Os–F9···F2Os–F9 –C1···F2 iii –C1 iii 2.873 2.873 143, 102 143, 102 Os–F9···N1 v 2.771 153 Os–F8···F9Os–F8iv–Os···F9 iv iv–Os iv 2.887 2.887 130, 137 130, 137 Os–F8···N1F···N interactions i F··· N2.857 –F ···N 165 F···N interactions v F···N –F···N F···C interactionsOs–F9··· N1 2.771 F···C 153 –F···C– Os–F9···N1Os–F8 v ···N1 i 2.857 2.771 165 153 Os–F7···C3 iii 2.770 139, 91 Os–F8···N1F···C interactions i F ···C2.857 –F ···C– 165 Os–F6···C2Os–F7 iii ···C3 iii 2.770 2.771 139, 91 128, 84 F···C interactions iii F···C –F···C– Symmetry codes: (i) −1/2 − x,Os–F6 −1/2 +··· y,1.5C2 − z; (ii) −1/22.771 + x,1/2 − y, −1/2 128, + z; 84 (iii) ½ − x, −1/2 + y,1.5 − z; (iv) Os–F7···C3 iii 2.770 139, 91 Symmetry−x, −y,2 − codes:z; (v) 1/2 (i) − +1/2 x,1/2− x,− y,1/2−1/2 + + z. y, 1.5 − z; (ii) −1/2 + x, 1/2 − y, −1/2 + z; (iii) 1/2 − x, −1/2 + y, 1.5 − z; (iv) −x, −y, 2 − z; (v) 1/2Os–F6···C2 + x, 1/2 − iiiy, 1/2 + z. 2.771 128, 84 Symmetry codes: (i) −1/2 − x, −1/2 + y,1.5 − z; (ii) −1/2 + x,1/2 − y, −1/2 + z; (iii) ½ − x, −1/2 + y,1.5 − z; (iv) −x, −y,2 − z; (v) 1/2 + x,1/2 − y,1/2 + z.

(a)

Figure 5. Cont. (a)

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(b)

(c)

Figure 5. Intermolecular interaction: (a) F···F; (b) F···N; (c) F···C in complex 1. Figure 5. Intermolecular interaction: (a)F···F; (b)F···N; (c)F···C in complex 1. 4. Conclusions 4. Conclusions The complex, C3F4N3OsF5, was obtained unexpectedly from the reaction mixture of OsF6, The complex, C3F4N3OsF5, was obtained unexpectedly from the reaction mixture of OsF6, SO2ClF, SbF5 and C3N3F3. The structure of the title compound was determined by single x-ray SO2ClF, SbF5 and C3N3F3. The structure of the title compound was determined by single x-ray diffraction analysis. The complex composed of a monodentate triazine anion (C3N3F4−) bonded to diffraction analysis. The complex composed of a monodentate triazine anion (C N F −) bonded pentafluoroosmium(VI) cation in an octahedral geometry. The crystal lattice3 displays3 4 many to pentafluoroosmium(VI) cation in an octahedral geometry. The crystal lattice displays many intermolecular interactions, F···F, F···N and F···C, leading to three dimensional structure. intermolecular interactions, F···F, F···N and F···C, leading to three dimensional structure. Acknowledgments: Monther A. Khanfar thanks the Deutsche Forschungsgemeinschaft (DFG) for a stipend Acknowledgments: Monther A. Khanfar thanks the Deutsche Forschungsgemeinschaft (DFG) for a stipend (Ref:(Ref: SE SE 293/42-1). 293/42-1). AuthorAuthor Contributions: Contributions:Monther Monther A. A. Khanfar Khanfar and and Hashem Hashem Shorafa Shorafa conceived conceived andand designed designed thethe experiments;experiments; MontherMonther A. A. Khanfar Khanfar performed performed the synthesesthe syntheses and prepared and prep theared single-crystal the single-crystal samples; Konradsamples; Seppelt Konrad performed Seppelt single-crystalperformed single-crystal analysis, Basem analysis, F. Ali Basem helped F. in Ali the helped data analysis; in the Basemdata analysis; F. Ali and Basem Monther F. Ali A. and Khanfar Monther wrote A. the paper. Khanfar wrote the paper Conflicts of Interest: The authors declare no conflict of interest. Conflicts of Interest: The authors declare no conflict of interest. References References 1. Khanfar, M.A.; Seppelt, K. Fluorinated benzene cations. J. Fluor. Chem. 2015, 179, 193–197. [CrossRef] 1. Khanfar, M.A.; Seppelt, K. Fluorinated benzene cations. J. Fluor. Chem. 2015, 179, 193–197. 2. Shorafa, H.; Mollenhauer, D.; Paulus, B.; Seppelt, K. The two structures of the hexafluorobenzene radical 2. Shorafa, H.;+ Mollenhauer, D.; Paulus, B.; Seppelt, K. The two structures of the hexafluorobenzene radical cation C6F6 . Angew. Chem. Int. Ed. 2009, 48, 5845–5847. [CrossRef][PubMed] cation C6F6+. Angew. Chem. Int. Ed. 2009, 48, 5845–5847. 3. Chen, X.; Wang, X.; Sui, Y.; Li, Y.; Ma, J.; Zuo, J.; Wang, X. Synthesis, characterization, and structures of 3. Chen, X.; Wang, X.; Sui, Y.; Li, Y.; Ma, J.; Zuo, J.; Wang, X. Synthesis, characterization, and structures of a a persistent aniline radical cation. Angew. Chem. Int. Ed. 2012, 51, 11878–11881. [CrossRef][PubMed] persistent aniline radical cation. Angew. Chem. Int. Ed. 2012, 51, 11878–11881. 4. Marchetti, F.; Pinzino, C.; Zacchini, S.; Pampaloni, G. Long-Lived radical cations of monocyclic arenes at 4. Marchetti, F.; Pinzino, C.; Zacchini, S.; Pampaloni, G. Long-Lived radical cations of monocyclic arenes at room temperature obtained by nbf5 acting as an oxidizing agent and counterion precursor. Angew. Chem. room temperature obtained by nbf5 acting as an oxidizing agent and counterion precursor. Angew. Chem. Int. Ed. 2010, 49, 5268–5272. [CrossRef][PubMed] Int. Ed. 2010, 49, 5268–5272.

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