Substitution reactions of IF5

Using silyl protected organic hydroxo compounds substitution of fluorine in IF₅ is successful.Reacting IF₅ with Si(OCH₃)₄ in CH₃CN or SO₂ using different molar ratios it was shown that in the series IF_5?n(OCH₃)_n only the first member IF₄(OCH₃) (n=1) is stable enough to be isolated. The product in solution with n=2 bismutates to products with n=1 and n=3 if isolated as solids. The last one decomposes to the new oxo compound IF₂O(OCH₃) under elimination of CH₃OCH₃. With n=4,5 only redox reaction products could be isolated.IF₂O(OCH₃) can also be obtained by treating IF₄(OCH₃) with (CH₃)₆Si₂O. Similarly reaction of IF₅ with the disiloxane represents a new method to win IOF₃. Excess of the oxygen transfer reagent leads to formation of IO₂F and I₂O₅. An other oxo compound, IO(CH₃COO)₃, can be prepared by disolving IF₅, IOF₃ or IO₂F in acetic acid anhydride.Reactions of IF₅ with trimethylsilyl protected fluorinated benzoic acids R_fCOOSi(CH₃)₃ (R_f = C₆F₅, 4HC₆F₄) appeared to be independent of the educts molar ratios because the only products are IF(R_fCOO)₄.In order to stabilize iodine (V) derivates with bifunctional chelating oxo ligands we applicated bis(trimethylsilyl) pinacolate, and in smooth reactions we yielded IF₃[OC(CH₃)₂C(CH₃)₂O] and IF[OC(CH₃)₂  C(CH₃)₂O]₂, in which iodine is part of five membered heterocyclic rings. The ¹⁹F-nmr-spectra are consistent with the diolate occupying the axiale and equatorial positions.An extension of the silyl method is the new synthesis of C₆F₅IF₄ which could be obtained in the smooth reaction of IF₅ with stochiometric amounts of Si(C₆F₅)₄.     

Mono‐ and Perfluoroaryliodine(III) Cyano Compounds – Synthesis,Reactivity, and Structure

C₆F₅I(CN)₂ and x‐FC₆H₄I(CN)₂ (x = 2, 3, 4) were isolated from reactions of the corresponding aryliodine difluorides ArIF₂ and a stoichiometric excess of Me₃SiCN in CCl₃F (0 °C) or CH₂Cl₂ (20 °C), respectively. In addition, x‐FC₆H₄I(CN)₂ compounds were synthesized in good yields on alternative routes, namely from 3‐ or 4‐FC₆H₄I(OC(O)CH₃)₂ or 4‐FC₆H₄I(OC(O)CF₃)₂ or from 4‐FC₆H₄IO and Me₃SiCN in CH₂Cl₂ at 20 °C. In the 1 : 1 reaction of C₆F₅IF₂ and Me₃SiCN a lower temperature was necessary to suppress partial disubstitution and to obtain the first example of a new type of aryliodine(III) cyanide compounds, C₆F₅I(CN)F. 4‐FC₆H₄I(CN)F could be isolated from the equimolar reaction of 4‐FC₆H₄IF₂ and Me₃SiCN in CH₂Cl₂ even at 20 °C. The new products were characterized by multi‐NMR and Raman spectroscopy. The molecular structures of C₆F₅I(CN)₂, 3‐ and 4‐FC₆H₄I(CN)₂, C₆F₅I(CN)F, and 4‐FC₆H₄I(CN)F are discussed and compared with that of C₆F₅IF₂. The reactivity of C₆F₅I(CN)F towards fluoride acceptors EF_n (BF₃, AsF₅) and R_xEX_?x (C₆F₅SiF₃, C₆H₅SiF₃, C₆H₅PF₄, Me₃SiCl, Me₃SiC₆F₅) were investigated and showed differing reaction patterns (fluoride abstraction, aryl transfer, chloride transfer). Besides the molecular entities C₆F₅I(CN)F and C₆F₅I(CN)Cl, the corresponding iodonium salts [C₆F₅(CN)I][BF₄] and [C₆F₅(CN)I][AsF₆] were isolated. The thermal stability of ArI(CN)₂ and ArI(CN)F, neat and in solution, as well as the reactivity of 4‐FC₆H₄I(CN)₂ towards the Lewis acid BF₃ are reported.     

Pentafluorphenyliod(III)-Verbindungen. 2. Fluor-Aryl Substitution an Iodtrifluorid: Synthese von Pentafluorphenylioddifluorid C6F5IF2 und Bis(pentafluorphenyl)iodonium Pentafluorphenylfluoroboraten [(C6F5)2I]+[(C6F5)nBF4−n]−

Pentafluorophenyliodine(III) Compounds. 2. Fluorine-Aryl Substitution Reactions on Iodinetrifluoride: Synthesis of Pentafluorophenyliodinedifluoride C₆F₅IF₂ and Bis(pentafluorophenyl)iodonium Pentafluorophenylfluoroborates[(C₆F₅)₂I]⁺[(C₆F₅)_nBF_4?n]^? Mono- and disubstitution can be achieved in the fluorine-aryl substitution reaction on the low-temperature phase IF₃ in CH₂Cl₂ at ?78°C depending on the aryl transfer reagent. With B(C₆F₅)₃ [(C₆F₅)₂I]⁺ [(C₆F₅)_nBF_4?n]^? (68% yield) and with Cd(C₆F₅)₂ C₆F₅IF₂ (97% yield) is obtained whereas with C₆F₅SiMe₃ no fluorine-aryl substitution takes place on IF₃ even under basic conditions (EtCN or F^? addition). At ?78°C in EtCN solution IF₃ does not disproportionate but attacks the solvent under formation of HF.     

Explored routes to unknown polyfluoroorganyliodine hexafluorides, RFIF6

Two routes to R_FIF₆ compounds were investigated: (a) the substitution of F by R_F in IF₇ and (b) the fluorine addition to iodine in R_FIF₄ precursors. For route (a) the reagents C₆F₅SiMe₃, C₆F₅SiF₃, [NMe₄][C₆F₅SiF₄], C₆F₅BF₂, and 1,4-C₆F₄(BF₂)₂ were tested. C₆F₅IF₄ and CF₃CH₂IF₄ were used in route (b) and treated with the fluoro-oxidizers IF₇, [O₂][SbF₆]/KF, and K₂[NiF₆]/KF. The observed sidestep reactions in case of routes (a) and (b) are discussed. Interaction of C₆F₅SiX₃ (X = Me, F), C₆F₅BF₂, 1,4-C₆F₄(BF₂)₂ with IF₇ gave exclusively the corresponding ring fluorination products, perfluorinated cyclohexadiene and cyclohexene derivatives, whereas [NMe₄][C₆F₅SiF₄] and IF₇ formed mixtures of C₆F_nIF₄ and C₆F_nH compounds (n = 7 and 9). CF₃CH₂IF₄ was not reactive towards the fluoro-oxidizer IF₇, whereas C₆F₅IF₄ formed C₆F_nIF₄ compounds (n = 7 and 9). C₆F₅IF₄ and CF₃CH₂IF₄ were inert towards [O₂][SbF₆] in anhydrous HF. CF₃CH₂IF₄ underwent C-H fluorination and C-I bond cleavage when treated with K₂[NiF₆]/KF in HF. The fluorine addition property of IF₇ was independently demonstrated in case of perfluorohexenes. C₄F₉CFCF₂ and IF₇ underwent oxidative fluorine addition at −30 °C, and the isomers (CF₃)₂CFCFCFCF₃ (cis and trans) formed very slowly perfluoroisohexanes even at 25 °C. The compatibility of IF₇ and selected organic solvents was investigated. The polyfluoroalkanes CF₃CH₂CHF₂ (PFP), CF₃CH₂CF₂CH₃ (PFB), and C₄F₉Br are inert towards iodine heptafluoride at 25 °C while CF₃CH₂Br was slowly converted to CF₃CH₂F. Especially PFP and PFB are new suitable organic solvents for IF₇.     

A first methodical approach to salts with unsymmetrical fluorophenyl(pentafluorophenyl)difluoroiodonium(V) cations [Rf(RF)IF2] (Rf=x-FC6H4, x=2, 3, 4; RF=C6F5)

A promising approach to the unknown type of [Ar′(Ar)IF₂]X salts is offered. x-FC₆H₄IF₄ (x=2, 3, 4) reacts with C₆F₅BF₂ in CH₂Cl₂ and forms [x-FC₆H₄(C₆F₅)IF₂][BF₄] salts in good yields. For [4-FC₆H₄(C₆F₅)IF₂][BF₄] the fluoro-oxidizer property is shown in reactions with weakly reducing agents like E(C₆F₅)₃ (E=P, As, Sb, Bi) and ArI (Ar=4-FC₆H₄, C₆F₅). The fluorine/aryl substitution method is also applied to the synthesis of [(4-FC₆H₄)₂IF₂][BF₄], an example with two identical aryl groups in the difluoroiodonium(V) moiety.     

Perfluoralkyljod-verbindungen: Darstellungen und eigenschaften von CF3JO,CF3JOF2 und CF3JO2

Perfluoroalkyl iodine compounds: preparations and properties of CF₃IO, CF₃IOF₂, and CF₃IO₂. The trifluoromethyl iodine compounds CF₃IO, CF₃IOF₂, and CF₃IO₂ are formed from the reactions of CF₃I, CF₃IF₂ or CF₃IF₄ with ozone or silicon dioxide respectively. Their preparartions, properties, ¹⁹F-nmr spectra, and ir spectra are described.     

Pentafluorphenyliod(V)-Verbindungen. 2. Pentafluorphenyliodtetrafluorid C6F5IF4: Synthese durch Fluor-Aryl-Substitution an IF5 — Eigenschaften und Struktur. Strukturanalyse der monovalenten Iodstammverbindung C6F5I

Pentafluorophenyliodine(V) Compounds. 2. Pentafluorophenyliodine Tetrafluoride C₆F₅IF₄: Synthesis via Fluorine-Aryl-Substitution on IF₅ — Properties and Structure. Structural Analysis of the Monovalent Iodine Parent Compound C₆F₅I The nucleophilic fluorine-aryl substitution reaction on IF₅ with pentafluorophenyl, Bi(C₆F₅)₃, leads to C₆F₅IF₄ in good yields and high purity. The thermal stability of C₆F₅IF₄ and its NMR spectrometric behaviour in solution will be described. The crystal structure of C₆F₅IF₄ will be discussed in comparison to IF₅. In addition data of the molecular and crystal structure of the monovalent iodine parent compound C₆F₅I will be given.     

[(C6F5)2IF2][BF4], the First Salt with the Electrophilic Cation [(C6F5)2IF2]+: Synthesis,Reactivity, and Structure

The substitution of hypervalently bonded fluorine atoms in C₆F₅IF₄ was performed with C₆F₅BF₂ and resulted in the new salt [(C₆F₅)₂IF₂][BF₄]. The iodonium(V) salt was characterized by multi‐NMR and Raman spectroscopy and X‐ray crystal structure analysis. The fluorinating ability of the new electrophilic cation [(C₆F₅)₂IF₂]⁺ was exemplified in reactions with monovalent iodine compounds (C₆F₅I, p‐FC₆H₄I, and I₂) and with electron‐poor tri(organyl)pnictanes ER₃ (E = P, As, Sb, Bi; R = C₆F₅). In a heterogeneous reaction with CsF in MeCN the [(C₆F₅)₂IF₂]⁺ cation forms the dinuclear [{(C₆F₅)₂IF₂}₂F]⁺ cation.     

Kristallstruktur,Infrarot‐ und Ramanspektren von Kupfertrihydrogenperiodatmonohydrat,CuH3IO6 · H2O

Crystal Structure, Infrared and Raman Spectra of Copper Trihydrogenperiodate Monohydrate, CuH₃IO₆ · H₂O The hitherto unknown compound CuH₃IO₆ · H₂O was studied by X‐ray, IR‐ and Raman spectroscopic methods. The crystal structure was determined by X‐ray single‐crystal studies (space group P2₁2₁2₁, Z = 4, a = 532.60(10), b = 624.00(10), c = 1570.8(3) pm, R1 = 1.85%, 1559 unique reflections (I > 2σ(I))). Isolated, meridionally configurated H₃IO₆^2– ions are coordinated to the copper ions forming double‐ropes in [100]. These ropes are connected in [010] and [001] by hydrogen bonds. The copper ions possess a square pyramidal co‐ordination with the hydrate H₂O on top. The infrared and Raman spectra as well as group theoretical treatment are presented and discussed with respect to the strength of the hydrogen bonds and the co‐ordination of the CuO₅₍₊₁₎ polyhedra and the H₃IO₆^2– ions at the C₁ lattice sites. The hydrogen bonds of the H₂O molecules and H₃IO₆^2– ions (HO–H…O–IO₅H₃ and H₂IO₅O–H…O–IO₅H₃) greatly differ in strength, as shown from both the respective O…O distances: 282.6 and 298.6 pm (H₂O), and 258.8, 259.7, and 270.9 pm (H₃IO₆^2–) and the OD stretching modes of isotopically dilute samples: 2498 and 2564 cm^–1 (90 K) (HDO), and 1786, 2024, and 2188 cm^–1 (H₂DIO₆^2–). The IO stretching modes of the H₃IO₆^2– ions (696–788 cm^–1 and 555–658 cm^–1, 295 K) display the different strength of the respective I–O and I–O(H) bonds (r_I–O: 181.1–188.3 pm and 189.2–194.5 pm).     

Polysulfonylamine. XLVI Molekülkomplexe von Di(organosulfonyl)aminen mit Dimethylsulfoxid und Triphenylphosphinoxid. Röntgenstrukturanalyse von Di(4-fluorbenzolsulfonyl)amin-Dimethylsulfoxid(2/1)

Polysulfonyl Amines. XLVI. Molecular Adducts of Di(organosulfonyl)amines with Dimethyl Sulfoxide and Triphenylphosphine Oxide. X-Ray Structure Determination of Di(4-fluorobenzenesulfonyl)amine-Dimethyl Sulfoxide(2/1) From equimolar solutions of the respective components in CH₂Cl₂/petroleum ether, the following crystalline addition compounds were obtained: (X? C₆H₄SO₂)₂NH …? OS(CH₃)₂, where X = H, 4? CH₃, 4? Cl, 4? Br, 4? I, 4? NO₂ or 3? NO₂; [(4? F? C₆H₄SO₂)₂NH]₂ · (OS(CH)₃)₂ ( 8 ); (4? I? C₆H₄SO₂)₂NH · OP(C₆H₅)₃. A (2/1) complex of (4? F? C₆H₄SO₂)₂NH with OP(C₆H₅)₃ could not be isolated. The solid-state structure of the (2/1) compound 8 is compared with the known structure of the (1/1) complex (CH₃SO₂)₂NH · OS(CH₃)₂. The crystallographic data for 8 at ?95°C are: monoclinic, space group C2/c, a = 2 369.9(13), b = 1 006.8(4), c = 2 772.6(13) pm, β = 110.71(4)°, U = 6.187 nm³, Z = 8. Two N? H …? O hydrogen bonds with N …? O 275 and 280 pm connect the disulfonylamine molecules with the dimethyl sulfoxide molecule. The O atom of the latter has a trigonal-planar environment consisting of the S atom and the two hydrogen bond H atoms.     

Beiträge zur chemie des iodpentafluorids teil III. Chelatisierung und strukturisomerie bei α,β-methylierten IOD(V)-α,β-ethandiolat-fluoriden

We report metathetical reactions of IF₅ with series of α,β-trimethylsilylated ethanediolates with increasing numbers of CH₃-groups in α- and β-positions. Short lived intermediates IF₄[OC₂H_4?n(CH₃)_nO]X with X = Si(CH₃)₃ or IF₄ and stable chelates IF₃[OC₂H_4?n(CH₃)_nO] and IF[OC₂H_4?n(CH₃)_nO]₂ (n = 0–4) are observed and characterized. Time and temperature dependence of ¹⁹F-NMR-spectra in relation to degree of methylation, arrangement and stereo-chemistry are discussed referring to previously published mono- and polynuclear I(V)-compounds containing a series of monodentate alcoholates CH_3?n(CH₃)_nO^? and (CH₃)₃CCH₂O^? (n = 0,2,3) [1,2] and of bidentate alcoholates ^?O(CH₂)_nO^? (n = 2,3,4,5,6,12) [1]. In contrast to aliphatic α,β-diolates the aromatic diolates 1,2-C₆H₄(O^?)₂, 1,2-C₆Cl₄(O^?)₂ rapidly undergo redox reactions even at low temperatures.     

Fluorinated phosphorus compounds: Part 6. The synthesis of bis(fluoroalkyl) phosphites and bis(fluoroalkyl) phosphorohalidates

Reaction of phosphorus trichloride with tert-butanol and fluoroalcohols gave bis(fluoroalkyl) phosphites (R_FO)₂P(O)H in 42-89% yield, where R_F=HCF₂CH₂, H(CF₂)₂CH₂, H(CF₂)₄CH₂, CF₃CH₂, C₂F₅CH₂, C₃F₇CH₂, (CF₃)₂CH, (FCH₂)₂CH, CF₃(CH₃)₂C, (CF₃)₂CH₃C, CF₃CH₂CH₂, C₄F₉CH₂CH₂ and C₆F₁₃CH₂CH₂. Treatment of these with chlorine in dichloromethane gave the bis(fluoroalkyl) phosphorochloridates (R_FO)₂P(O)Cl in 49-96% yield. The chloridate (CF₃CH₂O)₂P(O)Cl was isolated in much lower yield from the interaction of thionyl chloride with bis(trifluoroethyl) phosphite. Heating the latter in dichloromethane with potassium fluoride and a catalytic amount of trifluoroacetic acid gave the corresponding fluoridate (CF₃CH₂O)₂P(O)F in 84% yield. Treatment of bis(trifluoroethyl) phosphite with bromine or iodine gave the bromidate (CF₃CH₂O)₂P(O)Br and iodidate (CF₃CH₂O)₂P(O)I in 51 and 46% yield, respectively. The iodidate is the first dialkyl phosphoroiodidate to have been isolated and characterised properly—its discovery lags behind the first isolation of a dialkyl phosphorochloridate by over 130 years. The fluoroalkyl phosphoryl compounds are generally more stable than known unfluorinated counterparts.     

Synthesen und Eigenschaften von Tris(perfluoralkyl)arsen- und -antimon(III,V)-Verbindungen

Preparations and Properties of Tris(perfluoroalkyl) Arsenic and Antimony(III, V) Compounds As(R_f)₃ and Sb(R_f)₃ (R_f?C₂F₅, C₄F₉, C₆F₁₃) are prepared in good yields by the polar reactions of AsCl₃ and SbCl₃ with bis(perfluoroalkyl) cadmium compounds as colourless liquids or solids. The oxidation of As(C₂F₅)₃ and Sb(C₂F₅)₃ with XeF₂ gives the difluorides M(C₂F₅)₃F₂ (M?As, Sb). As(C₂F₅)₃Cl₂ is prepared by chlorination of As(C₂F₅)₃ in the presence of AlCl₃, while Sb(C₂F₅)₃Cl₂ is formed in the reaction of Sb(C₂F₅)₃F₂ with (CH₃)₃SiCl. During the reaction of M(C₂F₅)₃F₂ with (CH₃)₃SiBr ¹⁹F-NMR spectroscopic evidence is found for M(C₂F₅)₃ Br₂. The thermal decompositions of M(C₂F₅)₃F₂ mainly yield C₄F₁₀ and M(C₂F₅)F₂, while the thermal decompositions of M(C₂F₅)₃Cl₂ yield M(C₂F₅)₂Cl and C₂F₅Cl. The properties and spectroscopic data of the new compounds are described.     

Beiträge zur chemie des iodpentafluorids teil II. Iod(V)-verbindungen mit α,ω-difunktionellen alkoholaten

Nucleophilic substitution reactions of iodine pentaflurode with a series of homologous bifunctional alcoholates ^?O(CH₂)_nO^? (n=2,3,4,5,6,12), a geminal dialcoholate CC?₃ CH(O^?)₂ and a trifunctional alcoholate CH₃C(CH₂O^?)₃ protected by (CH₃)₃Si - groups are reported. Systems with short CH₂ - chains (n<4) first form short lived species IF₄[O(CH₂)_nO]X (X = SiMe₃, IF₄) which rearrange to mononuclear chelates IF₃[O(CH₂)_nO] of high stability. Dialcoholates with long CH₂-chains (n>4) behave as bridging ligands forming stable multinuclear compounds IF₄[O(CH₂)_nO]IF₄ and {IF₃[O(CH₂)_nO]}_m (m≥2). 1,4-Butanediolate is on the border line of the two systems.Products with greater substitution IF[O(CH₂)_nO]₂ (n=2,3) and IF₂(OCH₂)₃CCH₃ are also characterized.The dependence of ¹⁹F-NMR-shifts on the nature and arrangement of ligands is discussed.     

Decomposition and byproducts from reactions involving pentafluorophenyl-grignard and lithium reagents. a GC/MS study

Decomposition and side reactions of pentafluorophenylmagnesium bromide and pentafluorophenyllithium, when used in syntheses, have been investigated using GC/MS techniques. Reactions with reagents such as C₆F₅X (X = H, F, Cl, Br, I), C₆F₄X₂ (X = H, Cl), C₆F₃Cl₃, C₆H₆, (C₆X₅)₃P (X = H, F), (C₆X₅)₃P=O (X = H, F), (C₆X₅)Si(CH₃)₃ (X = H, F) and (CH₃)_4-nSiCl_n, n = 1, 2, in ether or ether/n-hexane were studied.In addition to the principal reaction of synthetic use, namely the replacement of a halogen by a pentafluorophenyl group, two types of side reactions were observed. These were (i) intermolecular loss of LiF via a nucleophilic substitution, and (ii) intramolecular loss of LiF, followed by the addition of either, inorganic salts such as lithium or magnesium halides, or organometal compounds such as organolithium or Grignard reagent present in the system. GC/MS proved to be an ideal method of monitoring such organometallic reaction systems, although it was sometimes not possible to identify byproducts as a particular isomer.     

Synthesis and structures of the six-coordinate donor-acceptor complexes R3(C6H4O2)Sb…L (R=Ph, L=OSMe2 or ONC5H5; R=Me, L=ONC5H5 or NC5H5) and R3(C2H4O2)Sb…L (R=Ph, L=ONC5H5; R=Cl or C6F5, L=OPPh3)

One-pot oxidation of R₃Sb (R=Ph, Me, Cl, or C₆F₅) withtert-butyl hydroperoxide in the presence of 1,2-diols and monodentate donor compounds was studied. The structures of the resulting neutral organic donor-acceptor Sb^V complexes, Ph₃(C₆H₄O₂)Sb…OSMe₂, Ph₃(C₆H₄O₂)Sb…ONC₅H₅, Me₃(C₆H₄O₂)Sb…ONC₅H₅, Me₃(C₆H₄O₂)Sb…NC₅H₅, Ph₃(C₂H₄O₂)Sb…ONC₅H₅, and Cl(C₆F₅)₂(C₂H₄O₂)Sb…OPPh₃, were established by X-ray diffraction analysis. In these complexes, the coordination environment about the Sb atoms is a distorted octahedron. The Sb?O(N) distances and the Sb?O?E angles (E=S, N, or P) vary over wide ranges.     

A Widely Applicable Synthetic Approach to Alk‐1‐yn‐1‐yl(polyfluoroorganyl)‐iodonium Salts [(RC≡C)(R′)I][BF4]

The reaction of alkynyldifluoroboranes RC≡CBF₂ (R = (CH₃)₃C, CF₃, (CF₃)₂CF) with organyliodine difluoride R′IF₂ bearing electron‐withdrawing polyfluoroorganyl groups R′ = C₆F₅, (CF₃)₂CFCF=CF, C₄F₉, and CF₃CH₂ leads to the corresponding alkynyl(organyl)iodonium salts [(RC≡C)(R′)I][BF₄]. This approach uses a widely applicable method as demonstrated for a representative series of polyfluorinated aryl‐, alkenyl‐, and alkyliodine difluorides. Generally, these syntheses proceed with good yields and deliver pure iodonium salts. The distinct electrophilic nature of their [(RC≡C)(R′)I]⁺ cations is deduced from multinuclear magnetic resonance data. Within the series of new iodonium salts [CF₃C≡C(C₄F₉)I][BF₄] is an intrinsic unstable one and decomposed forming CF₃C≡CI and C₄F₁₀.     

Aryl(pentafluorphenyl)iodoniumtetrafluoroborate: allgemeine Synthesemethode,typische Eigenschaften und strukturelle Gemeinsamkeiten

Pentafluorophenyliodine(III) Compounds. 4 [1] Aryl(pentafluorophenyl)iodoniumtetrafluoroborates: General Method of Synthesis, Typical Properties, and Structural Features Aryl(pentafluorophenyl)iodoniumtetrafluoroborates [Ar′Ar″I][BF₄] (Ar′ = C₆F₅, Ar″ = C₆H₅, o‐C₆H₄F, m‐C₆H₄F, p‐C₆H₄F, 2,6‐C₆H₃F₂, 3,5‐C₆H₃F₂, 2,4,6‐C₆H₂F₃, 3,4,5‐C₆H₂F₃, C₆F₅) are prepared in good yields and high purity by the reaction of C₆F₅IF₂ with Ar″BF₂ in CH₂Cl₂. This convenient method can be applied generally to many iodonium compounds. Thermal and spectroscopic properties (¹H, ¹³C, ¹⁹F NMR, IR, Raman) are reported and discussed. The solid state structures of six iodonium compounds show significant cation‐anion interactions which result in two different arrangements: a dimer with a 8‐membered ring or polymers with infinite zigzag chains. Ab initio calculations on prototypes of aryliodonium cations show relations between the kind of the aryl group (C₆H₅ vs. C₆F₅) and structural parameters as well as charges. By means of ¹⁹F NMR the σ_I‐ and σ_R‐constants of the [C₆F₅I]⁺‐substituent are determined.     

A Dimer of Hydrogen Cyanide Stabilized by a Lewis Acid

A highly labile dimer of hydrogen cyanide, HCN???HCN, was extracted from liquid HCN by adduct formation with the bulky Lewis acid B(C₆F₅)₃, affording HCN???HCN?B(C₆F₅)₃, which was fully characterized. The influence of the solvent (HCN, CH₂Cl₂, and aromatic hydrocarbons) on the crystallization process was studied, revealing dimer formation when using HCN or CH₂Cl₂ as solvent, whereas aromatic hydrocarbons led to the formation of monomeric arene??HCN?B(C₆F₅)₃ adducts, additionally stabilized by η⁶‐coordination of the aromatic ring system similar to well‐known half‐sandwich complexes.     

Fluorphosphorylamide

The preparation of some new phosphorus-fluoroamides of the type RP(O)FNH₂ is described (R = CH₃O-, C₆H₅O-, NH₂-, C₂H₅O-, CH₃NH-, C₂H₅NH-, C₆H₅-, C₆H₁₁-, C₂H₅-, CH₃-, and C₆H₅S-). All of the R? P(O)FNH₂ compounds were prepared at ?80°C in diethylether from the corresponding difluorides RP(O)F₂ and ammonia: RP(O)F₂ + 2NH₃ → RP(O)FNH₂ + NH₄F. When P(O)FCl₂ is reacted with ammonia in a molar ratio of 1:4, the hitherto unknown diamide of the series P(O)F_3?n(NH₂)_n (n = 1,2,3) is formed. As starting compounds, CH₃OP(O)F₂ and CH₃NHP(O)F₂ were obtained for the first time. The shifts of characteristic valency frequencies and some nmr data are discussed in homologous series.