Fluorine reaction with methane

Ring fluorination is observed in reactions of protected aniline derivatives, with the ojp ratio of the products, e.g. 11-13, being dependent on the substituent 5 nitrobenzene is unreactive towards electrophilic substitution. The polymerization process may be studied by di-fluorobis(fluoroxy)methane reactions with variousfluoro-substituted benzene derivatives (hexa-... 

METHANE TETRABROMHJE (558-13-4) Violent reaction with fluorine, hexylcyclo-hexyldilead, oxygen, potassium, potassium acetylene-1,2-dioxide, sodium azide, uranium(III) hydride. Mixtures with finely divided aluminum, lithium, magnesium, potassium-sodium alloy, titanium, zinc can form a friction- or shock-sensitive explosive material. Incompatible with decaborane. Attacks active metals. 

Violent explosions occur when fluorine directly contacts liquid hydrocarbons, even at —210 with anthracene or turpentine, or solid methane at — 190°C with liquid fluorine. Many lubricants ignite in fluorine [1,2]. Contact and reaction under carefully controlled conditions with catalysis can now be effected smoothly [3], Gaseous hydrocarbons (town gas, methane) ignite in contact with fluorine, and mixtures with unsaturated hydrocarbons (ethylene, acetylene) may explode on exposure to sunlight. Each bubble of fluorine passed through benzene causes ignition, but a rapid stream may lead to explosion [4],... 

Fluorination of tris(fluorosulfonyl)methane (10) with xenon difluoride in dichlorodifluoro-methane solution gives fluorotris(fluorosulfonyl)methane in quantitative yield.24 In contrast, no fluorination product has been obtained in the reaction of tris(trifluoromethylsulfonyl)meth-ane with xenon difluoride.25... 

Bromofluoromenthane has been prepared in high yield using a one-step reaction with bromine, hydrogen fluoride and methane in the presence of an aluminum trifluoride fluidized bed or fluorinated aluminum catalysts optionally containing cobalt or nickel between 450 and 500°C.20... 

Finally, fluorinated carboxylic acids react with epoxides (trimethylaluminum-catalyzed).- and conveniently with diazo conipounds. Cycloaddition is observed with diazo-methane. Reaction of compound 7 with trifluoroacetic acid alone is relatively slow (Freon 113, reflux, 12 h, for completion of reaction) however, catalytic amounts of copper(ll) perchlorate increase the rate of formation of ester 8 (rt, 5 min). ... 

Methane does not react with iodine at all. With fluorine it reacts so vigorously that, even in the dark and at room temperature, the reaction must be carefully controlled the reactants, diluted with an inert gas, are mixed at low pressure. We can, therefore, arrange the halogens in order of reactivity. 

Another highly fluorinated rare earth y9-diketonate, 21 (Ln = Pr, Eu, Ho dppm = di(perfluoro-2-propoxypropionyl)methanate), showed itself to be a delicate reagent, not only for accomplishing high chemoselectivity in Mukaijama aldol reactions with aldehydes and ketene silyl acetals (KSA) [123], for it was attributed with a mode of stereomodulating catalysis in the aldol reaction of alkoxy aldehydes with KSA (eqs. (12) and (13)). 

An example of a chain reaction is the reaction of methane with fluorine to give CH3F and HF ... 

In order to compare the C-H bonds, AMI wavefunctions were calculated for methane and for the hydrofluoromethanes, orientating each molecule such that a C-H bond lay along the z-axis. Localised molecular orbitals were produced using the population localisation method and values of >4b(—1) calculated (see Table 6). The AMI calculations reproduce the experimental observation that the C-H bond length is insensitive to increasing fluorination. Nevertheless, the C-H bonds in these molecules do show a marked variation in chemical reactivity. This is evident from the rate constants and from the activation energies for H-atom abstraction by free radicals. The reaction with OH is of particular... 

By-products. The presence in the products of small quantities of compounds which would arise from combination of free radical intermediates can provide evidence for a free radical process. For example, the explosive reaction of methane with fluorine gives mainly hydrogen fluoride and a mixture of mono-, di-, tri- and tetrafluoromethanes, but small quantities of fluorinated ethanes, including C2F6, are also produced. These two-carbon products cannot be readily explained on the basis of possible molecular reactions (see reaction 6.16), but would arise naturally as combination products of the fluorinated methyl radicals produced in a radical chain reaction sequence (reaction 6.17). 

Small-signal gain measurements have also been conducted for an HF chemical laser by Gensel et al. 12°). The reaction of fluorine atoms with methane has been used to pump the HF amplifier. Thus the inversion is produced exclusively by... 

PHENYL METHANE (108-88-3) CtH, CjHsCHj Forms explosive mixture with air [explosion limits in air (vol %) 1.4 to 6.7 flash point 39°F/4°C cc autoignition temp 896°F/480°C Fire Rating 3]. Violent reaction with strong oxidizers, bromine, bromine trifluoride, chlorine, hydrochloric acid-sulfuric acid mixture, l,3-dichloro-5,5-dimethyl-2,4-imidazolididione, dinitrogen tetraoxide, fluorine, nitric acid (cone.). 

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