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Perchlorylbenzene
Perchlorylbenzene (C6H5ClO3, PhClO3, is an aromatic compound prepared by direct electrophilic perchlorylation of benzene using perchloryl fluoride and aluminum trichloride: The compound is described as a somewhat shock-sensitive oily liquid. It exhibits low chemical reactivity and is inert towards acidic (HCl (aq.)) or reducing (LiAlH4, H2/Pd) conditions. However, it undergoes hydrolysis upon reflux in aqueous KOH to afford phenol, and undergoes aromatic nitration to afford the ''meta''-nitration product, as expected for a strongly –''I'', –''M'' substituent. It and its derivatives have been investigated as novel energetic materials analogous to nitro compounds. See also * Electrophilic aromatic substitution * Aromatic sulfonation * Aromatic nitration In organic chemistry, nitration is a general class of chemical processes for the introduction of a nitro group into an organic compound. The term also is applied incorrectly to the different process of forming nitrate ester ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrophilic Aromatic Substitution
Electrophilic aromatic substitution is an organic reaction in which an atom that is attached to an aromatic system (usually hydrogen) is replaced by an electrophile. Some of the most important electrophilic aromatic substitutions are aromatic nitration, aromatic halogenation, aromatic sulfonation, and alkylation and acylation Friedel–Crafts reaction. Illustrative reactions The most widely practised example of this reaction is the ethylation of benzene. :: Approximately 24,700,000 tons were produced in 1999. (After dehydrogenation and polymerization, the commodity plastic polystyrene is produced.) In this process, acids are used as catalyst to generate the incipient carbocation. Many other electrophilic reactions of benzene are conducted, although on a much smaller scale; they are valuable routes to key intermediates. The nitration of benzene is achieved via the action of the nitronium ion as the electrophile. The sulfonation with fuming sulfuric acid gives benzenesulfonic ac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aromatic Sulfonation
Aromatic sulfonation is an organic reaction in which a hydrogen atom on an arene is replaced by a sulfonic acid functional group in an electrophilic aromatic substitution. Aryl sulfonic acids are used as detergents, dye, and drugs. Stoichiometry and mechanism Typical conditions involve heating the aromatic compound with sulfuric acid: :C6H6 + H2SO4 → C6H5SO3H + H2O Sulfur trioxide or its protonated derivative is the actual electrophile in this electrophilic aromatic substitution. To drive the equilibrium, dehydrating agents such as thionyl chloride can be added. :C6H6 + H2SO4 + SOCl2 → C6H5SO3H + SO2 + 2 HCl Chlorosulfuric acid is also an effective agent: :C6H6 + HSO3Cl → C6H5SO3H + HCl In contrast to aromatic nitration and most other electrophilic aromatic substitutions this reaction is reversible. Sulfonation takes place in concentrated acidic conditions and desulfonation is the mode of action in a dilute hot aqueous acid. The reaction is very useful in protectin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perchloryl Fluoride
Perchloryl fluoride is a reactive gas with the chemical formula . It has a characteristic sweet odor that resembles gasoline and kerosene. It is toxic and is a powerful oxidizing and fluorinating agent. It is the acid fluoride of perchloric acid. In spite of its small enthalpy of formation (Δ''H''f° = −5.2 kcal/mol), it is kinetically stable, decomposing only at 400 °C. It is quite reactive towards reducing agents and anions, however, with the chlorine atom acting as an electrophile. It reacts explosively with reducing agents such as metal amides, metals, hydrides, etc. Its hydrolysis in water occurs very slowly, unlike that of chloryl fluoride. Synthesis and chemistry Perchloryl fluoride is produced primarily by the fluorination of perchlorates. Antimony pentafluoride is a commonly used fluorinating agent: : + 3 HF + 2 → + + 2 reacts with alcohols to produce alkyl perchlorates, which are extremely shock-sensitive explosives. In the presence of a Lewis acid, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitration
In organic chemistry, nitration is a general class of chemical processes for the introduction of a nitro group into an organic compound. The term also is applied incorrectly to the different process of forming nitrate esters between alcohols and nitric acid (as occurs in the synthesis of nitroglycerin). The difference between the resulting molecular structures of nitro compounds and nitrates is that the nitrogen atom in nitro compounds is directly bonded to a non-oxygen atom (typically carbon or another nitrogen atom), whereas in nitrate esters (also called organic nitrates), the nitrogen is bonded to an oxygen atom that in turn usually is bonded to a carbon atom (nitrito group). There are many major industrial applications of nitration in the strict sense; the most important by volume are for the production of nitroaromatic compounds such as nitrobenzene. Nitration reactions are notably used for the production of explosives, for example the conversion of guanidine to nitrog ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
