684-16-2

Hexafluoroacetone was readily formed by circulating a gaseous mixture of hexafluoropropene and oxygen over platinum group metals supported on carbon.Reaction temperatures, ranging from 130 to 170 deg C, gave both high selectivity and conversion for the hexafluoroacetone formation using a Pd/C catalyst.

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The utility model provides equipment for directly producing bis-o-xylylene hexafluoroacetone through HFPO, which comprises an isomerization kettle, a gas-liquid separation kettle, a rectification column, a condenser, an HFA storage tank and a condensation kettle, the bottom of the isomerization kettle is connected to the bottom of the gas-liquid separation kettle, and the upper part of the gas-liquid separation kettle is connected with the upper part of the isomerization kettle; wherein the top of the gas-liquid separation kettle is connected to the bottom of the rectification column through apipeline, the upper end of the rectification column is respectively connected to an HFPO feed port and an HFA storage tank of the isomerization kettle, and a condenser is also arranged on a connecting pipeline between the rectification column and the HFA storage tank; and the HFA storage tank is connected to the condensation kettle. According to the device, synchronous HFA production and consumption can be realized, risks caused by HFA transportation and storage are avoided, and meanwhile, the reaction catalyst can be directly recycled through the device, so that the cost is saved, and the harm to the environment is avoided.

We present the first synthesis of air/moisture-stable λ3-bromanes (9and10) by using a cyclic 1,2-benzbromoxol-3-one (BBX) strategy. X-ray crystallography and NMR and IR spectroscopy ofN-triflylimino-λ3-bromane (12) revealed that the bromine(III) center is effectively stabilized by intramolecular R-Br-O hypervalent bonding. This strategy enables the synthesis of a variety of air-, moisture-, and benchtop-stable Br-hydroxy, -acetoxy, -alkynyl, -aryl, and bis[(trifluoromethyl)sulfonyl]methylide λ3-bromane derivatives.

The invention discloses a method for preparing hexafluoroacetone by taking perfluoropropylene oxide as a raw material. The method comprises the following steps: adding the perfluoropropylene oxide, acatalyst and water into a reaction kettle according to a weight ratio of 1: (0.1-0.5): (1-5), carrying out isomerization reaction at 10-80 DEG C for 1-5 hours, and distilling and purifying to obtain the hexafluoroacetone, wherein by condensing substituted phenol and Merrifield resin, and mixing and compounding with a carrier, the catalyst is obtained. According to the method, the Merrifield resinloaded substituted phenol is used as the catalyst for the first time, and is applied to the method for preparing the hexafluoroacetone by taking the perfluoropropylene oxide as the raw material, so that a new preparation thought is provided, and particularly for fluorine chemical enterprises, self-produced intermediate products can be fully utilized. The raw materials of the catalyst are easy to obtain, the cost is low, and the economic benefit is good; the catalyst is simple in preparation process and mild in preparation condition. The yield of the hexafluoroacetone reaches 95% or above, theoperation is safe, and the catalyst can be continuously used.

The synthesis and characterization of the new perfluorinated hypochlorite, undecafluoro-tert-pentyl hypochlorite, (C2F5)(F3C)2COCl, is reported. Its gas-phase infrared, UV/Vis and NMR spectra have been recorded and its spectroscopic properties are discussed and compared with quantum-chemical predictions and those of other known perfluorinated hypochlorites such as RFOCl [RF = F3C, (F3C)3C, (C2F5)(F3C)2C]. A synthetic route to otherwise difficult to access perfluorinated dialkyl peroxides, RFOORF, is also provided by low-temperature photolysis of the corresponding hypochlorite.

The invention discloses a novel process for synthesizing hexafluoroacetone. The novel process comprises the following steps: reacting trifluoroacetic anhydride with a metal fluoride in a solvent to obtain trifluoroacetyl fluoride, adding an alkaline salt and trifluoroacetate, and carrying out a coupling reaction on trifluoroacetate and trifluoroacetyl fluoride to obtain the product hexafluoroacetone. The product yield is 95% or above, and the product purity is higher than 96%.

Nitroarenes are used as the coupling partners in the preparation of sulfonamides via the insertion of sulfur dioxide. A three-component reaction of arylboronic acids, nitroarenes, and potassium metabisulfite under copper catalysis proceeds smoothly, giving rise to a range of sulfonamides in good to excellent yields with broad substrate scope. Various functional groups including hydroxyl, cyano, amino, and carbonyl are all tolerated. A plausible mechanism is proposed, showing that arylsulfinate is the intermediate and the copper-assisted interaction of the nitroarene and arylsulfinate is the key step. This approach is also extended to the late-stage modification of a currently marketed drug (flutamide).

A ditriflate derivative of 2-iodoxybenzoic acid (IBX) was prepared by the reaction of IBX with trifluoromethanesulfonic acid and characterized by single crystal X-ray crystallography. IBX-ditriflate is the most powerful oxidant in a series of structurally similar IBX derivatives which is best illustrated by its ability to readily oxidize hydrocarbons and the oxidation resistant polyfluoroalcohols.

The invention relates to a pharmaceutical raw material hexafluoroacetone synthesis method, which mainly comprises: adding 3 mol 2,3-dihydroxy-hexafluoroisopentane and 4-6 mol N-methylpropionamide solution to a reaction container, increasing the temperature of the solution to 70-80 DEG C, maintaining for 60-80 min, adding 2-3 mol bismuth molybdate, continuously carrying out the reaction for 50-70 min, reducing the temperature to 40-50 DEG C, carrying out pressure reducing distillation, collecting the distillate at a temperature of 80-89 DEG C, washing with a metacresol solution, washing with am-chloroaniline solution, and re-crystallizing with a methoxytoluene solution to obtain the crystal hexafluoroacetone.

The indirect ("ex-cell") electrochemical synthesis of benzoxazoles from imines using a redox mediator based on the iodine(I)/iodine(III) redox couple is reported. Tethering the redox-active iodophenyl subunit to a tetra-alkylammonium moiety allowed for anodic oxidation to be performed without supporting electrolyte. The mediator salt can be easily recovered and reused. Our "ex-cell" approach toward the electrosynthesis of benzoxazoles is compatible with a range of redox-sensitive functional groups. An unprecedented concerted reductive elimination mechanism for benzoxazole formation is proposed on the basis of control experiments and DFT calculations.

The invention discloses a method for preparing 1,1,1,3,3,3-hexafluoroacetone by gas phase fluorination. The method comprises that 1,1,1,3,3,3-hexachloroacetone as a raw material undergoes a one-step gas phase fluorination reaction in the presence of a fluorination catalyst at a reaction temperature of 300 DEG C to produce 1,1,1,3,3,3-hexafluoroacetone, wherein a mole ratio of hydrogen fluoride to the organic matter is 10: 1 and contact time is 10s. The fluorination catalyst is a ferric compound-loaded catalyst. A preparation method of the fluorination catalyst comprises utilizing alumina, magnesium oxide or calcium oxide as carriers, dipping the carriers in an iron soluble salt and one of soluble salts of metal cocatalysts such as copper, manganese, zinc, nickel, cobalt and lanthanum to obtain a catalyst precursor with a mass ratio of iron to the carriers of 2-20% and cocatalyst content of 0.5-2wt%, and carrying out drying, roasting and HF fluorination. The prepared fluorination catalyst has the characteristics of environment-friendliness, low price, good catalytic activity, good stability and regeneration easiness. The method realizes high-selectivity synthesis of the 1,1,1,3,3,3-hexafluoroacetone.

Smog chambers with in situ FTIR detection were used to measure rate coefficients in 700 Torr of air and 296 ± 2 K of: k(Cl+(CF3)2CHOCH3) = (5.41 ± 1.63) × 10-12, k(Cl+(CF3)2CHOCHO) = (9.44 ± 1.81) × 10-15, k(Cl+CF3C(O)OCH3) = (6.28 ± 0.98) × 10-14, k(OH+(CF3)2CHOCH3) = (1.86 ± 0.41) × 10-13, and k(OH+(CF3)2CHOCHO) = (2.08 ± 0.63) × 10-14 cm3 molecule-1 s-1. The Cl atom initiated oxidation of (CF3)2CHOCH3 gives (CF3)2CHOCHO in a yield indistinguishable from 100%. The OH radical initiated oxidation of (CF3)2CHOCH3 gives the following products (molar yields): (CF3)2CHOCHO (76 ± 8)%, CF3C(O)OCH3 (16 ± 2)%, CF3C(O)CF3 (4 ± 1)%, and C(O)F2 (45 ± 5)%. The primary oxidation product (CF3)2CHOCHO reacts with Cl atoms to give secondary products (molar yields): CF3C(O)CF3 (67 ± 7)%, CF3C(O)OCHO (28 ± 3)%, and C(O)F2 (118 ± 12)%. CF3C(O)OCH3 reacts with Cl atoms to give: CF3C(O)OCHO (80 ± 8)% and C(O)F2 (6 ± 1)%. Atmospheric lifetimes of (CF3)2CHOCH3, (CF3)2CHOCHO, and CF3C(O)OCH3 were estimated to be 62 days, 1.5 years, and 220 days, respectively. The 100-year global warming potentials (GWPs) for (CF3)2CHOCH3, (CF3)2CHOCHO, and CF3C(O)OCH3 are estimated to be 6, 121, and 46, respectively. A comprehensive description of the atmospheric fate of (CF3)2CHOCH3 is presented.

Hexafluoroacetone or a hydrate thereof is produced with a high yield by subjecting a 1-fluoro-4,4-bis(trifluoromethyl)-2,3,5-trioxolanyl ether compound represented by the general formula: wherein R is an alkyl group having 1 to 8 carbon atoms, an aryl group, or a benzyl group, which has been obtained by ozone oxidation of a heptafluoroisobutenyl ether compound, to a reduction reaction in the presence of a reducing agent selected from dialkyl sulfide containing an alkyl group having 3 or 4 carbon atoms, diaryl sulfide, diaryl disulfide, and diaralkyl sulfide.

New powerful hypervalent iodine(v) oxidants, tosylate and mesylate derivatives of 2-iodoxybenzoic acid (IBX), were prepared by the reaction of IBX with the corresponding sulfonic acids. Single crystal X-ray crystallography of the diacetate derivative of IBX-tosylate revealed an unusual heptacoordinated iodine geometry without any significant intermolecular secondary interactions.

Thiocarbonyl S-oxides (sulfines) derived from aliphatic and cycloaliphatic thioketones were irradiated in argon matrices at 10 K, and the resulting oxathiiranes were identified by comparison of computed and experimental IR spectra. Upon photolysis at 10 K, depending on the substitution pattern, the oxathiiranes underwent either H-shift reactions or regioselective ring enlargements to form the corresponding thioesters. After warming of the matrix material to 38-40 K, the oxathiiranes underwent fast desulfurization to yield the corresponding ketones. Density functional theory (DFT) computations at the B3LYP/6-311+G(3df,3pd) level suggest that the desulfurizations of oxathiiranes occurred as bimolecular processes with activation enthalpies near 0 kcal mol-1.

The endocannabinoid transporter and FAAH are sites of modulation that allow pharmacological enhancement of protective endocannabinergic signals. Selective inhibitors of the transporter and inhibitors of FAAH caused additive augmentation of endogenous signaling events mediated by the cannabinoid CB1 receptor.Disruption of such signals has been shown to prevent neuronal maintenance processes and increase vulnerability to brain damage. Here, blocking endocannabinoid inactivation enhanced cannabinergic activity and ameliorated cellular disturbances associated with excitotoxicity. Modulating the endocannabinoid system in this way also prevented excitotoxic behavioral abnormalities including memory impairment. Collectively, these results indicate that increasing endocannabinoid responses by inhibiting the endocannabinoid transported and/or the inhibiting FAAH leads to molecular, cellular, and functional protection against excitotoxic insults like stroke and traumatic brain injury.

A dielectric gaseous compound which exhibits the following properties: a boiling point in the range between about ?20° C. to about ?273° C.; non-ozone depleting; a GWP less than about 22,200; chemical stability, as measured by a negative standard enthalpy of formation (dHf0); a toxicity level such that when the dielectric gas leaks, the effective diluted concentration does not exceed its PEL; and a dielectric strength greater than air.

Processes for preparing hexafluoroisobutene epoxide (HFIBO) from CH2=C(CF3)2 (HFIB) are provided. The processes can be carried out in substantial absence of oxidation catalysts.

A new synthetic procedure for the preparation of perfluorinated ketones from nonfiuorinated sec-alcohols was developed. A key step in the synthetic route was a liquid-phase direct fluorination reaction with elemental fluorine. Direct fluorination of a partially fluorinated ester, which was prepared from a nonfiuorinated sec-alcohols and a perfluorinated acyl fluoride, followed by thermal elimination, gave a perfluorinated ketone and the starting perfluorinated acyl fluoride, which could be recycled. Application to the synthesis of a precursor polyfluoroketone for fluoropolymer resists for 157nm microlithography was also established.

Perfluoro(5-methylene-2,2-dimethyl-1,3-dioxolane) (1) was synthesized by utilizing a direct fluorination reaction. Compound 1 was an entirely novel monomer with difluoromethylene at position 5 on the dioxolane ring as an unprecedented polymerization site. It successfully polymerized with tetrafluoroethylene to afford copolymers, which had Tg values in the range of 60-90 °C. The content of monomer 1 in the obtained polymers was less than 20 mol%, which seemed insufficient for giving various unique properties to polymers. However, each polymer was expected to be a superior material because of their advanced thermal stability. Comparison with copolymers of 2,2-bis(trifluoromethyl)-4,5-difluoro-1,3-dioxole and tetrafluoroethylene is also discussed.

In the presence of copper(I) iodide as catalyst, a variety of carbonyl compounds, such as aldehydes, ketones and acid anhydrous, could be trifluoromethylated with sodium trifluoroacetate to give the corresponding alcohols in moderate to high yields, and a possible mechanism was proposed to explain the roles of catalyst and solvent in the reaction system.

A tetracoordinate 1,2-iodoxetane oxide was prepared, and it oxidized alcohols to the corresponding aldehydes and ketones in good to moderate yields under mild conditions. A tetracoordinate 1,2-iodoxetane was prepared by the fluorination of a tricoordinate 1,2-iodoxetane with xenon difluoride followed by hydrolysis. The tetracoordinate 1,2-iodoxetane oxidized alcohols and a sulfide to the corresponding aldehydes and ketones, and a sulfoxide, respectively, in good to moderate yields under mild conditions.

The present invention provides a process for the preparation of hexafluoroacetone characterized by bringing hexafluoro-1,2-epoxypropane into contact with at least one catalyst selected from the group consisting of titanium oxide catalysts and fluorinated titanium oxide catalysts to isomerize hexafluoro-1,2-epoxypropane; and a process for the preparation of hexafluoroacetone hydrate characterized by absorbing the hexafluoroacetone prepared by the above process into water to produce crude hexafluoroacetone hydrate, neutralizing the crude hexafluoroacetone hydrate with an alkali, and distilling the resulting mixture. According to the invention, high-purity hexafluoroacetone can be obtained by isomerization of hexafluoro-1,2-epoxypropane with little formation of by-products, and substantially acid-free high-purity hexafluoroacetone hydrate can also be obtained.

A process is disclosed for producing (CF3)2C=CH2, CF3CH=CF2, CF2=C(CF3)OCF2CHF2 and C6H5C(CF3)=CF2. The process involves contacting the corresponding fluorocarbon starting material selected from (CF3)2CFCH2F, (CF3)2CHF, (CF3)2CFOCF2CHF2 and C6H5CF(CF3)2, in the vapor phase, with a defluorination reagent selected from carbon, copper, iron, nickel and zinc at an elevated temperature of at least 300 DEG C.

The present invention relates to novel imidazolidine derivatives of formula I, wherein A, E, Z, R1, R2, R3, R4 and R5 have the meanings indicated in the claims. The compounds of formula I are valuable pharmaceutical active compounds which are suitable, for example, for the treatment of inflammatory diseases, including rheumatoid arthritis, or allergic diseases. The compounds of formula I are inhibitors of the adhesion and migration of leukocytes and/or antagonists of the adhesion receptor VLA-4 belonging to the integrins group. They are generally suitable for the treatment of diseases which are caused by an undesired extent of leukocyte adhesion and/or leukocyte migration or are associated therewith or in which cell-cell or cell-matrix interactions which are based on the interactions of VLA-4 receptors with their ligands play a role. The invention furthermore relates to processes for the preparation of the compounds of formula I, their use and pharmaceutical preparations which contain compounds of formula I.

The present invention relates to hydantoins of formula I, in which R is the residue of an amino carboxylic acid or of an amino carboxylic acid derivative, which is obtained formally by removing an NH2 group from an amino carboxylic acid or an amino carboxylic acid derivative, to the preparation thereof and to the use thereof as intermediates, in particular for preparing pharmaceutically active ingredients.

Compounds of the invention, useful as thrombin inhibitors and having therapeutic value in for example, preventing coronary artery disease, have the following structure: or a pharmaceutically acceptable salt thereof, wherein A is

Oxidation of hexafluoropropylene with molecular oxygen in a fixed bed of a catalyst (activated carbon promoted with alkali metal fluorides) was studied.

Ignition delay times have been measured behind reflected shock waves in ethane-oxygenargon mixtures at temperatures between 1150 and 1500 K and pre-ignition pressures between 10 and 14 atm. Delay times have been measured both by pressure rise and OH absorption at 307 nm. Kinetic modelling of the ignition delays has been made using the GRIMech 3.0 mechanism which with addition of several reactions involving HO2 radicals and an increase in the barrier for reaction between C2H5 and O2 can satisfactorily model delays over the studied equivalence ratios of φ= 1.7 to 0.68. Addition of 2H-heptafluoropropane up to 13 mol % (of ethane) had little inhibition effect on stoichiometric ethane-oxygen-argon mixtures but inhibited ignition in a mixture of φ= 1.5. A kinetic mechanism is presented to model the inhibition process. by Oldenbourg Wissenschaftsverlag, Muenchen.

Briefly, in one aspect, this invention provides a catalytic method of preparation of primary and secondary hydrofluoroethers, the process comprising reacting a fluorinated precursor material and an alkylating agent in the presence of a Lewis acid catalyst or a mixture comprising Lewis acid and Bronsted acid catalysts.

The kinetics of the oxidation of 2-propanol, 1,1,1-trifluoro-2-propanol, 1,1,1,3,3,3-hexafluoro-2-propanol, 1-phenyl-2,2,2-trifluoroethanol, 1-(4-methylphenyl)-2,2,2-trifluoroethanol, 1-(3-bromophenyl)-2,2,2-trifluoroethanol, and 1-(3-nitrophenyl)-2,2,2-trifluoroethanol by potassium tetraoxoferrate(VI) have been studied under basic conditions. The products are ketones, formed in almost quantitative yields, iron(III) hydroxide, and dioxygen. The reactions are characterized by substantial enthalpies of activation (40-60 kJ/mol), very unfavorable entropies of activation, large primary deuterium isotope effects, and a positive Hammett p value. Both acid and base catalysis are observed. Acid catalysis is attributed to formation of a more reactive oxidant, HFeO4-, at low pH. Base catalysis is attributed partly to the conversion of the reductants to alkoxide ions at high pH, and partly to the reaction of hydroxide ion with tetraoxoferrate(VI) to give a five-coordinated species, HOFeO43-, that reacts rapidly with nucleophiles. A reaction mechanism involving formation of an intermediate ferrate ester is proposed.

The first perfluoroalkyl hypobromites have been prepared by the reaction of bromine(I) fluorosulfate with perfluorinated tertiary alkoxides of general formula RfC(CF3)2ONa where Rf=CF3 or CF3CF2. These hypobromites are of lower thermal stability but they behave similarly to analogous hypochlorites and decompose rapidly above -20 °C to give CF3C(O) CF3 and either CF3Br or CF3CF2Br. New polyfluoroethers generated from the reaction of perfluoroalkyl hypobromites with fluoroalkenes have been characterized by 19F and 1H NMR spectroscopy, IR spectroscopy and MS.

A new Lewis acid - aluminum chlorofluoride - was demonstrated to be an effective catalyst for the isomerisation of fluoroolefins, polyfluorinated epoxides and cyclopropanes.At ambient temperature this catalyst converts perfluorobutadiene-1,3 into perfluorobutyne-2 and perfluoro(4-methylpentene-2) into perfluoro(2-methylpentene-2) in nearly quantitative yield.At 100 deg C, aluminum chlorofluoride causes the cleavage of perfluorinated tertiary amines. - Keywords: Electrophilic reactions; Fluorocarbons; Aluminum chlorofluoride; Lewis acid; NMR spectroscopy

The reactions of the HO-, CH3S-, CH2S- and CH2=C(CH3)-CH2- ions with three ketones (CF3COR; R=CH3, CF3, C6H5) and three esters of trifluoroacetic acid (CF3CO2R; R=CH3, C2H5 and C6H5) have been studied with use of Fourier Transform Ion Cyclotron Resonance (FT-ICR) mass spectrometry. All four negative ions react exclusively by proton transfer with CF3COCH3. With the other substrates, the HO- ion reacts by various pathways, such as proton transfer, SN2 substitution, E2 elimination and attack on the carbonyl group. The CH3S- ion is unreactive towards CF3COC6H5 but is able to react by hydride transfer, SN2, E2 and/or carbonyl attack with the remaining neutral species. The CH2S- radical anion reacts by electron transfer to afford stable molecular radical anions of CF3COCF3 and CF3COC6H5, whereas the main reaction with the two esters, CF3CO2CH3 and CF3CO2C2H5, is dissociative electron transfer leading to CF3CO2- and CF3- ions. The CH2=C(CH3)-CH2- anion displays a more complex reactivity pattern involving electron transfer, SN2, E2 as well as attack on the carbonyl group. Direct evidence for the occurrence of electron transfer as the initial step in an overall BAC2 type process has not been obtained for the systems studied. The reaction of the CH2S- ion with CF3CO2C6H5 was observed, however, to yield exclusively a CF3COCHS-. radical anion. Based upon the absence of a BAC2 process in the reaction of CH2S- with the methyl and ethyl esters of trifluoroacetic acid in combination with the facile occurrence of electron transfer from this radical anion, it is suggested that the CF3COCHS-. ion is formed by an initial electron transfer followed by coupling between the CH2S molecule and the CF3CO2C6H5- radical anion and subsequent loss of C6H5OH from the collision complex.

This invention relates to analogs of peptidase substrates in which the amide group containing the scissile amide bond of the substrate peptide has been replaced by an activated electrophilic ketone moiety. These analogs of the peptidase substrates provide specific enzyme inhibitors for a variety of proteases, the inhibition of which will have useful physiological consequences in a variety of disease states.

Polyfluorinated oxetanes are prepared in high yields by an electrophilic cycloaddition reaction between hexafluoroacetone and fluorinated ethylenes that is catalyzed by an anhydrous aluminum chlorofluoride Lewis acid.The reaction is regiospecific with hydrofluoroethylenes CHX=CF2 (X = H, F, Cl, Br), whereas halotrifluoroethylenes CFX=CF2 (X = Cl, Br) give nearly equal amounts of the isomeric oxetanes.Hexafluoropropylene oxide, which rapidly rearranges under the reaction conditions, can be substituted for hexafluoroacetone in this new oxetane synthesis.

A method of making hexafluoroacetone from hexafluoroacetone oxime comprising heating hexafluoroacetone oxime (or solvent complex thereof) with a concentrated mineral acid to yield hexafluoroacetone. Also a method of making hexafluoroacetone oxime from hexafluoroisobutyroyl carbanion alkylammonium salts. The oxime can be prepared by reacting the salts in solvent with an alkali or alkaline earth metal nitrite and subsequently decarboxylating and hydrolyzing the reaction product, or alternatively, reacting the salts in a solvent with dinitrogen tri- or tetra-oxide and subsequently decarboxylating and hydrolyzing the reaction product.

Reaction of the title azomethinimine (1) with nitrogen dioxide gives nitric oxide, hexafluoroacetone and 3,3-dimethyl-5,5-bis(trifluoromethyl)-1-pyrazoline (2) in high yield, while with the perfluoronitrosoalkanes RFNO (RF = CF3 and CF2CF2CF3) the products are hexafluoroacetone and the azimines 8a and 8b, respectively.The reactions involve initial cycloaddition involving the N=O bonds, followed by elimination of hexafluoroacetone and niric oxide to give 2 or of hexafluoroacetone to give 8.From reaction of 1 with nitrosyl chloride the major products are nitric oxide, 7-chloro-8,8,8-trifluoro-2-methyl-4,4,7-tris(trifluoromethyl) -5,6-diazaocta-1,5-diene (13) and 5,5-dimethyl-3,3-bis(trifluoromethyl)-1-pyrazolidine (14) formed via decomposition of the 1:1 adduct containing C-chloro and N-nitroso substituents.The oxyl (CF3)2NO. attacks azomethinimine 1 at carbon and the resulting 1:1 adduct decomposes to give hexafluoroacetone, the pyrazoline 2 and (CF3)2N. radicals which are trapped by the oxyl to afford the oxadiazapentane (CF3)2NON(CF3)2 (19).Secondary reaction then takes place involving attack of the oxygen atom of the oxadiazapentane on 1 at carbon to give hexafluoroacetone, N,N-bis(trifluoromethyl)amine and 3-methyl-5,5-bis(trifluoromethyl)-3--1-pyrazoline (21).This is confirmed by treatment of 1 with the oxadiazapentane 19.

Nucleophilic epoxidation of 3-chloropentafluoro-1-propene at PTC conditions afforded 3-chloropentafluoropropene-1,2-oxide, which was reacted with some oxygen and nitrogen nucleophiles to 3-chloro-3,3-difluoropropionic acid derivatives.With antimony pentafluoride, mixture of fluorinated acetones was obtained.

Halogenoalkylphenyl-alcohols, ketones and their hydrates of formula I, wherein R1 to R8 are as defined in the description, are useful as acetylcholinesterase inhibitors.

A synthesis for hexafluoroacetone using elemental fluorine is reported.Previously hexafluoroacetone and other ketones have been difficult to prepare using fluorination based syntheses.

Thermolysis of the azo compound (CF3)2NOC(CF3)2N=NC(CF3)2ON(CF3)2 (1) alone at 140 deg C gives nitrogen, hexafluoroacetone and the hydrazine (CF3)2NN(CF3)2 via (CF3)2N radical coupling in quantitative yield, while from decomposition in the presence of the alkenes CF2=CF2, CF2=CFCl and CF2=CHF (ca. 1:1 molar ratio) the major products are the dimer 2, trimer (CF3)2N(CF2CFCl)2CFClCF2N(CF3)2 and a mixture of tetramers (CF3)2N(C2HF3)4N(CF3)2, respectively.The (CF3)2N radicals generated from 1 can also be trapped with bromine (CF3)2NBr> and nitroso compounds (CF3)2NNRO (R=CF3 and Ph)>, but with ethyne or benzene near-quantitative yields of the amine (CF3)2NH are obtained.

The low temperature reaction of TeF5OCl with the fluorocarbon iodides, CF3I, C2F5I, n-C3F7I, and i-C3F7I results in the formation of RfI(OTeF5)2 adducts.Except for the trifluoromethyl derivative these are stable, colorless compounds.The trifluoromethyl adduct decomposes above -78 deg C to give the previously unknown CF3OTeF5.The perfluoroethyl and n-propyl adducts decompose at 120 deg C or under UV radiation giving C2F5OTeF5 and n-C3F7OTeF5, respectively.These reactions constitute a new synthesis of primary RfOTeF5 compounds.Attempts to extend this synthesis to secondary fluorocarbon iodides were unsuccessful.

A Barbier procedure, under moderate pressure, was used for the trifluoromethylation of various carbonyl compounds, starting from trifluoromethyl bromide and zinc in pyridine.Trifluoromethyl methanols were obtained from aldehydes and trifluoromethyl ketones from activated esters.Ethyl benzoate, or acetone, induced the formation of the solvated trifluoromethylzinc derivatives which did not react with carbonyl cpompounds.Consequently, the Barbier condensation in that case was considered to involve nascent organometallics reacting near the zinc surface.The reaction with sulphur dioxide, leading to trifluoromethanesulphinate, showed striking differences from that of carbonyl compounds.It was shown that the main pathway occcured in solution.This condensation was interpreted by the initial formation of sulphur dioxide radical anion, which reacts with trifluoromethyl bromide by a single-electron-transfer process.Attempts to condense iminium salts failed when a hydrogen atom was lacking in the α position.When the iminium ion can be transformed in situ to an enamine, a reaction occured, leading to α-trifluoromethyl ketones.This condensation was interpreted by a chain mechanism involving trifluoromethyl radicals.

Three 17-electron transition-metal complex negative ions LM(CO)x-1.- ((OC)Fe(NO)2.-, (OC)2Co(NO).-, and (η3-C3H5)Co(CO)2.-) and two parent molecular anion radicals LM(CO)x.- ((C3H5)Co(CO)3.- and CpCo(CO)2.-) were generated by electron impact on the corresponding LM(CO)x complexes in the gas phase. The ion-molecule reactions of these five metal complex negative ions were studied with the neutral molecules PF3, PMe3, NO, SO2, olefins with electron-donating and -withdrawing vinyl substituents, acetone and certain fluorinated derivatives, biacetyl, O2, CO, and CS2. In general, the LM(CO)x-1.- complexes and CpCo(CO)2.- reacted by ligand substitution involving the associative mechanism. In many cases, the product ions of adduct formation and ligand substitution were directly observed in the same reaction. These ligand substitution reactions appear to take advantage of the abbility of the NO, η3-C3H5, and Cp ligands to reduce their hapticities as the neutral ligand bonds to the metal. The reaction of (C3H5)Co(CO)3.- with PF3 occurred by fragmentation of the allyl radical. This latter result was considered to occur by radical β-fragmentation of the excited acyl complex [C3H5C(=O)Co(CO)2(PF3) .-]* formed by CO insertion into the Co-allyl bond. Both parent molecular anion radicals were observed to undergo electron transfer with several of the neutral substrates yielding EA((η3-C3H5)Co(CO)3) = EA(CpCo(CO)2) = 0.62 ± 0.1 eV; EA(η3-C3H5)Co(CO)2) = 0.9 ± 0.2 eV was also measured. The results of the reactions of the parent LM(CO)x.- species with the neutral ligands were consistent with their structures having a 17-electron configuration about the metal with η3-Cp and η1-C3H5 ligands.

Reaction of zinc with bromotrifluoromethane in pyridine gives poorly reactive trifluoromethyl zinc derivatives in the presence of ethyl benzoate whereas the Barbier condensation occurs with activated esters, like ethyl trifluoroacetate or ethyl oxalate, and cyclic anhydrides.

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New methods for the synthesis of bis(trifluoromethyl)sulfine (sulfoxide) (9) are reported.Pyrolysis, photolysis, and hydrolysis of the compound were investigated as well as the typical behaviour in reactions with the thiocarbonyl group (thiophosgene), with anthracene (Diels-Alder addition) and halogens.

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