Thermolyse des halogenures de perfluoroalcanesulfonyle

Perfluoroalkanesulfonyl chlorides [R_FSO₂Cl ; R_F  CF₃, C₂F₃, C₄F₉], decompose thermally to give the corresponding perfluoroalkyl chlorides with evolution of SO₂. The latter retards the reaction, but it is catalysed by copper which also inhibits the SO₂ effect. 2-methyl-2-nitrosopropane traps the perfluoroalkyl free radicals. In the presence of a perfluoroalkyl iodide [R′_FI ≠ R′_F≠R_F], other products, R_FI and R_FCl, are obtained. A free radical chain-mechanism is then suggested.On the other hand, perfluorobutanesulfonyl fluoride is very stable thermally.     

Oxydation anodique de iodoperfluoroalcanes dans les acides perfluoroalcanesulfoniques. Preparation de nouveaux esters sulfoniques totalement fluores RFSO3R'F a longues chaines

Perfluorinated sulphonic esters R_FSO₃R'_F and fluorosulphates FSO₃R'_F, are easily obtained by anodic oxidation of iodoperfluoroalkanes R'_FI in perfluoroalkane sulphonic acids R_FSO₃H (R_F  CF₃, C₂F₅, C₄F₉) and fluorosulphuric acid. With di-iodo compound I(CF₂)₄I, the mono and the diester can be selectively obtained. The alkaline hydrolysis of these esters produces perfluorinated carboxylic compounds. Polyfluorinated iodide R'_FCH₂CH₂I are also oxidized in similar conditions. The mechanism of the electrolytic reaction is discussed.     

New fluorinated polysiloxanes containing an ester function in the spacer. I. Synthesis and characterization

Unsaturated perfluoroalkyl esters derived from undecylenic acid: CH₂?CH? (CH₂)₈? COO? CH₂? CH₂? R_F (with R_F?C₆F₁₃, 2a and R_F?C₈F₁₇, 2b ) and C₈F₁₇? (CH₂)₁₀? COO? CH₂? CH?CH₂, 2c were prepared with excellent yields. Their hydrosilylation by methylhydrodimethylsiloxane copolymers of various Si? H contents gives new fluorinated polysiloxanes which were examined by ¹H- and ¹³C-NMR, GPC, differential scanning calorimetry, and optical polarizing microscopy. Polymers derived from compounds 2a and 2b exhibit mesomorphic structures. © 1994 John Wiley & Sons, Inc.     

Thermal stability of perfluoroalkanesulfonic acids and their anhydrides. New and easy approach to RFSO2ORF esters.

Perfluoroalkanesulfonic anhydrides (R_FSO₂)₂O when mixed with acids decompose into perfluoroalkanesulfonic esters R_FSO₂OR_F, thereby providing a new facile synthesis of these esters from perfluoroalkanesulfonic acids and phosphorus pentoxide.     

Metal complexes of fluorophosphines : III. Some oxidative addition reactions of a rhodiumtrifluorophosphine complex

Some oxidative addition reactions of (CH₃)₅C₅Rh(PF₃)₂ with various iodine compounds are described. Iodine reacts with (CH₃)₅C₅Rh(PF₃)₂ in benzene at room temperature to give the deep red crystalline diiodide (CH₃)₅C₅Rh(PF₃)I₂. The perfluoroalkyl iodides R_fI (R_f = CF₃, C₂F₅, n-C₃F₇, and n-C₇F₁₅) react with (CH₃)₅C₅Rh(PF₃)₂ in benzene at room temperature to give the orange to deep red (CH₃)₅C₅Rh(PF₃)(R_f)I (R_f = CF₃, C₂F₅, n-C₃F₇, and n-C₇F_l5). The IR and proton and fluorine NMR spectra of these new (pentamethylcyclopentadienyl)rhodium-trifluorophosphine complexes are discussed.     

Systematische untersuchungen über das verhalten von organozinnverbindungen gegenüber flüssigem schwefeldioxid III. SO2-disproportionierung bei einschiebungsreaktionen an tetraalkylstannanen

When liquid SO₂ is allowed to react with the tetraalkyltin compounds (CH₃)₄Sn and (C₂H₅)₄Sn at 60°, disproportionation of sulfur takes place resulting in the formation of the corresponding bis(trialyltin) sulfates, [R₃Sn]₂SO₄, and alkanethiosulfonic acid S-alkyl esters, RSO₂SR (R = CH₃, C₂H₅). The course of the reaction is discussed.     

Synthesen und Eigenschaften von Bis(perfluoralkyl)zink‐Verbindungen

Syntheses and Properties of Bis(perfluoroalkyl)zinc Compounds The conditions for the syntheses of bis(perfluoroalkyl)zinc compounds Zn(R_f)₂ · 2 D (R_f = C₂F₅, n‐C₃F₇, i‐C₃F₇, n‐C₄F₉, n‐C₆F₁₃, n‐C₇F₁₅, and n‐C₈F₁₇; D = CH₃CN, tetrahydrofurane, dimethylsulfoxide) are described. Mass spectra, thermal decompositions, ¹⁹F‐ and ¹³C‐NMR spectra are discussed.     

Synthesis of 2-(perfluoroalkyl)ethyl potassium sulfates based on perfluorinated Grignard reagents

The first example of nucleophilic substitution with perfluoroalkyl Grignard reagents on the sp³ carbon centre is described. Thus, a series of organometals R_F-MgBr, prepared from perfluorinated alkyl iodides R_F-I with R_F = C₄F₉, C₆F₁₃, C₈F₁₇, C₁₀F₂₁ and C₁₂F₂₅, reacted with 1,3,2-dioxathiolane-2,2-dioxide to afford the corresponding 2-(perfluoroalkyl)ethyl magnesium sulfates, which were isolated after metathesis to the corresponding potassium salts. In the model reaction, perfluorohexylmagnesium iodide was reacted with methyl triflate yielding polyfluorinated alkane. The attempts to extend the reaction to 1,3,2-dioxathiane-2,2-dioxide were unsuccessful due to its inferior reactivity and only reduced polyfluoroalkane and the product of coupling were detected in the reaction mixture. Polyfluorinated sulfates are easily hydrolyzed with hydrochloric or triflic acid to the corresponding alcohols, which is an alternative to standard transformation of perfluoroalkyl iodides to 2-(perfluoroalkyl)ethanols. Quantum-chemical calculations of the PES of the reaction with both sulfur-containing heterocycles found that the failure of the reaction with 1,3,2-dioxathiane-2,2-dioxide is caused by higher activation energy of the process.     

Synthese et reactivite d'organomagnesiens perfluores. V.[1] Synthese et identification de nouveaux composes perfluoroalkyles du mercure a chaine longue.

The reaction of mercuric salts HgY₂ or organic mercuric compounds R_HHgX with long chain perfluorinated Grignard reagents R_FMgBr leads to a series of new perfluoroalkyl mercury derivatives with the general formula R_FHgZ (R_F=C₄F₉, C₆F₁₃, C₈F₁₇ ; Z=R_F,R_H,Y with Y = I,Br,Cl, NO₃,OCOCH₃,OCOCF₃).The synthesis of these organomercuric compounds is described, and their spectroscopic properties are reported.     

Metallkomplexe mit biologisch wichtigen Liganden. CLVII [1] Halbsandwich‐Komplexe mit Isocyanoacetylaminosäureestern und Isocyanoacetyldi‐ und tripeptidestern („Isocyano‐Peptide”︁)

Metal Complexes of Biologically Important Ligands, CLVII [1] Halfsandwich Complexes of Isocyanoacetylamino acid esters and of Isocyanoacetyldi‐ and tripeptide esters (?Isocyanopeptides”?) N‐Isocyanoacetyl‐amino acid esters CNCH₂C(O) NHCH(R)CO₂CH₃ (R = CH₃, CH(CH₃)₂, CH₂CH(CH₃)₂, CH₂C₆H₅) and N‐isocyanoacetyl‐di‐ and tripeptide esters CNCH₂C(O)NHCH(R¹)C(O)NHCH(R²)CO₂C₂H₅ and CNCH₂C(O)NHCH(R¹)C(O)NHCH (R²)C(O)NHCH(R³)CO₂CH₃ (R¹ = R² = R³ = CH₂C₆H₅, R² = H, CH₂C₆H₅) are available by condensation of potassium isocyanoacetate with amino acid esters or peptide esters. These isocyanides form with chloro‐bridged complexes [(arene)M(Cl)(μ‐Cl)]₂ (arene = Cp*, p‐cymene, M = Ir, Rh, Ru) in the presence of Ag[BF₄] or Ag[CF₃SO₃] the cationic halfsandwich complexes [(arene)M(isocyanide)₃]⁺X^? (X = BF₄, CF₃SO₃).     

Reactivite comparee des perfluoroiodoalcanes (RFI) et des perfluoroalcoyl-2 iodo-1 ethanes (RFC2H4I) en presence de couple metallique zinc-cuivre dans les solvants phosphates d'alcoyles

Reactivity of perfluoroalkyl iodides R_FI and 1-perfluoroalkyl-2-iodoethanes R_FC₂H₄I, in presence of a zinc-copper couple in alkyl phosphates solvents, is described. R_FI and R_FC₂H₄I react via an organometalllc route to give per- and poly-fluoroorganozinc (R_FZnI and R_FC₂H₄ZnI) compounds. Then, in particular conditions, they react with alkyl to give phosphoro-fluorinated molecules (phosphinates, phosphine oxides, phosphines). The compounds's stabilities are studied.     

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.     

Azidoperfluoroalkanes: Synthesis and Application in Copper(I)‐Catalyzed Azide–Alkyne Cycloaddition

We report an efficient and scalable synthesis of azidotrifluoromethane (CF₃N₃) and longer perfluorocarbon‐chain analogues (R_FN₃; R_F=C₂F₅, ⁿ C₃F₇, ⁿ C₈F₁₇), which enables the direct insertion of CF₃ and perfluoroalkyl groups into triazole ring systems. The azidoperfluoroalkanes show good reactivity with terminal alkynes in copper(I)‐catalyzed azide–alkyne cycloaddition (CuAAC), giving access to rare and stable N ‐perfluoroalkyl triazoles. Azidoperfluoroalkanes are thermally stable and the efficiency of their preparation should be attractive for discovery programs.     

Fluorination of perfluoroalkylsulfenyl chlorides,perfluorodialkyl disulfides and perfluorodialkyl sulfides with chlorine monofluoride

In reactions with perfluoroalkylsulfenyl chlorides (R_fSCl; R_f = F₃, C₂F₅, n-C₃F₇, n-C₄F₉) and perfluoroalkyl disulfides (R_fSSR_f′; R_f = R_f′ = CF₃, R_f = CF₃, R_f′ = C₂F₅) at 25°, chlorine monofluoride acts primarily as a chlorinating and fluorinating reagent to give the corresponding perfluoroalkylsulfur chloride tetrafluorides, R_fSF₄Cl, in good yields. However, small amounts of perfluoroalkylsulfur pentafluorides, R_fSF₅, are also obtained. A mixture of the cis and trans isomers of bis(trifluoromethyl)sulfur tetrafluoride and of trifluoromethyl pentafluoroethylsulfur tetrafluoride has been formed by the reaction of the corresponding bis(perfluoroalkyl) sulfides and chlorine monofluoride. The new perfluoroalkylsulfur chloride tetrafluorides are colorless, unpleasant smelling liquids. The infrared, mass and ¹⁹F NMR spectral data, as well as thermodynamic and elementary analysis data, are given for the new compounds.     

The reactions of perfluoro- and α,α-dichloropolyfluoroalkanesulfinates

Sodium perfluoroalkanesulfinate, R_FSO₂Na [R_F?Cl(CF₂)₄, 1a; CF₃(CF₂)₅, 1b; Cl(CF₃)₆, 1c] reacted with bromine in aqueous solution to give the corresponding sulfonyl bromide R_FSO₂Br (2a-2c) and in acetonitrile or acetic acid, to form perfluoroalkyl bromide R_FBr (3a-3c). Heating in acetonitrile at 80°C, 2a-2c were converted smoothly into 3a-3c. However, reaction of sodium α,α-dichloropolyfluoroalkanesulfinate RCCl₂SO₂Na (R?CF₃, Cl(CF₂)n, n=2, 4, 6, 5a-5d) with bromine in aqueous solution gave directly the corresponding bromoalkanes 1-bromo-1,1-dichloropolyfluoroalkane RCCl₂Br (6a-6d). In aqueous potassium iodide solution, 1a-1c, 5a and 5b also reacted with iodine to form the corresponding iodo-polyfluoroalkane 4a-4c, 7a and 7b directly. 6a and 7a underwent free radical addition to alkene readily in the presence of free radical initiator and reacted with Na₂S₂O₄ in the usual way to form α,α-dichloropolyfluoroethane sulfinate (5a). 5a was stable in strong acid, but reacted with strong base to yield 10. 5a was oxidised by hydrogen peroxide to the sulfonate 11 and reduced by zinc in dilute acid to from the α-chloro sulfinate 12.     

The preparation of perfluorinated carboxylic esters and perfluoro carbonates

Aliphatic perfluorinated carboxylic esters have been prepared by two methods; (i) the reaction of the potassium salt of perfluoro 3-ethyl pent-3-ol, KOC(C₂F₅)₃, with perfluoro acid chlorides R_fCOCl, to yield perfluorinated esters of composition R_fCOOC(C₂F₅)₃, and (ii) the reaction of carbonyl chloride or thionyl chloride with a mixture of the potassium salt KOC(C₂F₅)₃ and perfluoro acid salts of the general formula KOCOR_f in a polar solvent. The product ester has the composition R_fCOOC(C₂F₅)₃, and in this instance carbon dioxide or sulphur dioxide is liberated during the reaction. A qualitative study of the thermal decomposition of a perfluoro ester has been made.A tertiary perfluoro carbonate of composition [(C₂F₅)₂CF₃CO]₂CO has been prepared by the reaction of phosgene with the potassium salt KOC(C₂F₅)₂CF₃ in a polar solvent. The intermediate acid chloride (C₂F₅)₂CF₃COCOCl can be isolated.     

Synthesis of symmetric and dissymetric bisperfluoroalkanesulfonylimides and evaluation of their inhibition on bovine carbonic anhydrase

This study describes a synthesis of symmetric and dissymmetric bis[(perfluoroalkane)‐sulfonyl]imides by the reaction of the sodium salt of perfluoroalkanesulfonamide R_FSO₂NH⁻Na⁺ (R_F = C₄F₉, C₆F₁₃, C₈F₁₇) with hexamethyldisilazane and perfluoroalkanesulfonylfluoride R_FSO₂F (R_F = C₄F₉, C₆F₁₃, C₈F₁₇). They are obtained, in two steps, in moderate overall yield. Moreover, this paper provides a study of their inhibition on bovine carbonic anhydrase. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:542–548, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20452     

Electron structure and reactivity of organofluorine compounds. 3. Mndo and ami calculations of the ground state of perfluoroalkyl chlorides,bromides, and iodides

The semiempirical quantum chemical MNDO and AMI methods were used to determine the equilibrium geometries and electron properties of molecules of perfluoroalkyl halides (R_FX): CF₃X, CF₃CF₂X, (CF₃)₂CFX, (CF₃)₃CX for X=Cl, Br, and I. It was determined that the effective charge on the Cl atom in R_FCl is negative, positive on the I atom in R_FI, and depends on R_F for the Br atom in R_FBr. The CF₃ group can act as either an electron acceptor or donor in various perfluoroalkyl halides. The strongest C–I bond in the perfluoroalkyl halides occurs with a tertiary RF group.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1059–1063, May, 1990.     

Synthese und Eigenschaften von Diethyldithiocarbaminsäureperfluororganylestern, (C2H5)2NC(S)SRf (Rf = CF3, C2F5, i‐C3F7, n‐C4F9, C6F5)

Syntheses and Properties of Perfluoroorgano Esters of the Diethyldithiocarbamic Acid, (C₂H₅)₂NC(S)SR_f (R_f = CF₃, C₂F₅, i‐C₃F₇, n‐C₄F₉, C₆F₅) Tetraethylthiuram disulfide reacts under different conditions with perfluoroorgano silver(I), AgR_f, and perfluoroorgano cadmium compounds, Cd(R_f)₂, to give the corresponding perfluoroorgano esters of diethyldithiocarbamic acid, (C₂H₅)₂NC(S)SR_f (R_f = CF₃, C₂F₅, i‐C₃F₇, n‐C₄F₉, C₆F₅), and metal diethyldithiocarbamates, AgSC(S)N(C₂H₅)₂ and Cd[SC(S)N(C₂H₅)₂]₂. The mechanisms of the reactions with AgR_f and Cd(R_f)₂ are discussed.     

The syntheses of fluorinated alkanesulfonamides and poly-(fluorinated alkanesulfonamides)

In order to synthesize poly-(fluorinated alkanesulfonamides) a series of model experiments were carried out: (1) reactions of fluorinated alkanesulfonyl fluorides with amines, (2) reactions of fluorinated alkanesulfonyl chloride with amines and (3) reactions of sodium salts of fluorinated alkanesulfonamides with alkyl iodides of fluorinated alkanesulfonic acid esters. Seventeen new fluorinated alkanesulfonamides were prepared in good yields, namely: R_FO(CF₂)₂SO₂NR¹R² (1a-h), R¹R²NSO₂R_FSO₂NR¹R² (2a-h) and [Cl (CF₂)₄O(CF₂)₂SO₂NH(CH₂)₃]₂ (3). Reaction of R_FSO₂NH₂ with equivalent amount of NaOCH₃ and methyl iodide was shown to give both the N-mono- and N,N-di-substituted amides. Consequently the N-monosubstituted alkanesulfonamides were chosen as monomers for syntheses of the poly-(fluorinated alkanesulfonamides) and two new polymers were synthesized. The effect of the condition of the polycondensation on M?_n of the polymers were discussed and elemental composition, ¹⁹F NMR, IR, M?_n, Tg, tensile strength, thermal and chemical stabilities of the polymers were measured. Several new perfluoroalkanesulfonyl chlorides CISO₂R_FSO₂Cl (4a-c) and fluorinated alkanesulfonic acid esters (6a-d) were synthesized. However, reaction of CFCl₂CF₂O(CF₂)₂SO₂F with AlCl₃ was found to give Cl₃CCF₂O(CF₂)₂SO₂F (5) instead of the expected sulfonyl chloride.