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4-nitrotoluene
4-Nitrotoluene or ''para''-nitrotoluene is an organic compound with the formula CH3C6H4NO2. It is a pale yellow solid. It is one of three isomers of nitrotoluene. Synthesis and reactions Together with other isomers, 4-nitrotoluene is prepared by nitration of toluene, commonly using titanium(IV) nitrate. It undergoes the reactions typical for nitrobenzene derivatives, e.g. hydrogenation gives ''p''-toluidine. Oxidation of the methyl substituent of 4-nitrotoluene has been extensively investigated. Depending on the conditions, oxidation yields 4-nitrobenzaldehyde diacetate, 4-nitrobenzenoic acid, and 4,4'-dinitrobibenzyl. Treatment of 4-nitrotoluene with bromine gives the 4-nitrobenzyl bromide. Applications The principal application involves its sulfonation to give the 4-nitrotoluene-2-sulfonic acid (with the –SO3H group adjacent to methyl). This species can be oxidatively coupled to produce stilbene derivatives, which are used as dyes. Representative derivatives include ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Disodium 4,4'-dinitrostilbene-2,2'-disulfonate
Disodium 4,4′-dinitrostilbene-2,2′-disulfonate is an organic compound with the formula (O2NC6H3(SO3Na)CH)2. This salt is a common precursor to a variety of textile dyes and optical brighteners Preparation and reactions The synthesis of disodium 4,4′-dinitrostilbene-2,2′-disulfonate begins with sulfonation of 4-nitrotoluene. This reaction affords 4-nitrotoluene-2-sulfonic acid. Oxidation of this species with sodium hypochlorite yields the disodium salt of 4,4′-dinitrostilbene-2,2′-disulfonic acid. The product is useful as its reaction with aniline derivatives results in the formation of azo dyes. Commercially important dyes derived from this compound include Direct Red 76, Direct Brown 78, and Direct Orange 40. Reduction gives 4,4′-diamino-2,2′-stilbenedisulfonic acid, which is a common optical brightener. History Arthur Green and André Wahl first reported the formation of disodium 4,4'-dinitrostilbene-2,2'-disulfonate using sodium hypochlorite Sodium h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Toluidine
There are three isomers of toluidine, which are organic compounds. These isomers are ''o''-toluidine, ''m''-toluidine, and ''p''-toluidine, with the prefixed letter abbreviating, respectively, ''ortho''; ''meta''; and ''para''. All three are aryl amines whose chemical structures are similar to aniline except that a methyl group is substituted onto the benzene ring. The difference between these three isomers is the position where the methyl group (–CH3) is bonded to the ring relative to the amino functional group (–NH2); see illustration of the chemical structures below. The chemical properties of the toluidines are quite similar to those of aniline, and toluidines have properties in common with other aromatic amines. Due to the amino group bonded to the aromatic ring, the toluidines are weakly basic. The toluidines are poorly soluble in pure water but dissolve well in acidic water due to formation of ammonium salts, as usual for organic amines. ''ortho''- and ''meta' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrotoluene
Mononitrotoluene or nitrotoluene (MNT or NT), is any of three organic compounds with the formula C6H4(CH3)(NO2). They can be viewed as nitro derivatives of toluene or as methylated derivatives of nitrobenzene. Mononitrotoluene comes in three isomers, differing by the relative position of the methyl and nitro groups. All are pale yellow with faint fragrances: * ''ortho''-nitrotoluene (ONT), ''o''-nitrotoluene, or 2-nitrotoluene. m.p. = -10.4 °C * ''meta''-nitrotoluene (MNT), ''m''-nitrotoluene, or 3-nitrotoluene. m.p. = 16 °C * ''para''-nitrotoluene (PNT), ''p''-nitrotoluene, or 4-nitrotoluene. m.p. = 44.5 °C Typical use of nitrotoluene is in production of pigments, antioxidants, agricultural chemicals, and photographic chemicals. ''Ortho''-mononitrotoluene and ''para''-mononitrotoluene can be also used as detection taggants for explosive detection. See also * Toluene * Dinitrotoluene * Nitrobenzene * Trinitrotoluene Trinitrotoluene (), more comm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Compound
In chemistry, organic compounds are generally any chemical compounds that contain carbon-hydrogen or carbon-carbon bonds. Due to carbon's ability to catenate (form chains with other carbon atoms), millions of organic compounds are known. The study of the properties, reactions, and syntheses of organic compounds comprise the discipline known as organic chemistry. For historical reasons, a few classes of carbon-containing compounds (e.g., carbonate salts and cyanide salts), along with a few other exceptions (e.g., carbon dioxide, hydrogen cyanide), are not classified as organic compounds and are considered inorganic. Other than those just named, little consensus exists among chemists on precisely which carbon-containing compounds are excluded, making any rigorous definition of an organic compound elusive. Although organic compounds make up only a small percentage of Earth's crust, they are of central importance because all known life is based on organic compounds. Liv ... [...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 nitrogua ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Toluene
Toluene (), also known as toluol (), is a substituted aromatic hydrocarbon. It is a colorless, water-insoluble liquid with the smell associated with paint thinners. It is a mono-substituted benzene derivative, consisting of a methyl group (CH3) attached to a phenyl group. As such, its systematic IUPAC name is methylbenzene. Toluene is predominantly used as an industrial feedstock and a solvent. As the solvent in some types of paint thinner, permanent markers, contact cement and certain types of glue, toluene is sometimes used as a recreational inhalant and has the potential of causing severe neurological harm. History The compound was first isolated in 1837 through a distillation of pine oil by the Polish chemist Filip Walter, who named it ''rétinnaphte''. In 1841, French chemist Henri Étienne Sainte-Claire Deville isolated a hydrocarbon from balsam of Tolu (an aromatic extract from the tropical Colombian tree '' Myroxylon balsamum''), which Deville recognized as simil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Titanium(IV) Nitrate
Titanium nitrate is the inorganic compound with formula Ti(NO3)4. It is a colorless, diamagnetic solid that sublimes readily. It is an unusual example of a volatile binary transition metal nitrate. Ill defined species called titanium nitrate are produced upon dissolution of titanium or its oxides in nitric acid. Preparation Similarly to its original method, Ti(NO3)4 is prepared by the nitration of titanium tetrachloride using dinitrogen pentoxide or chlorine nitrate: :TiCl4 + 4 N2O5 → Ti(NO3)4 + 4 ClNO2 Hydrated titanium nitrate, the nitrate salt of the aquo complex i(H2O)6sup>3+, is produced upon dissolution of titanium compounds in nitric acid. Structure The complex has D2d symmetry, with four bidentate nitrate ligands. The N-O distances are 1·29 Å and 1·185 Å (noncoordinated). Physical properties In the infrared spectrum, it absorbs strongly at 1635 cm−1, assigned to a N-O vibrational mode. It is soluble in nonpolar solvents silico ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrogenation
Hydrogenation is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst such as nickel, palladium or platinum. The process is commonly employed to reduce or saturate organic compounds. Hydrogenation typically constitutes the addition of pairs of hydrogen atoms to a molecule, often an alkene. Catalysts are required for the reaction to be usable; non-catalytic hydrogenation takes place only at very high temperatures. Hydrogenation reduces double and triple bonds in hydrocarbons. Process Hydrogenation has three components, the unsaturated substrate, the hydrogen (or hydrogen source) and, invariably, a catalyst. The reduction reaction is carried out at different temperatures and pressures depending upon the substrate and the activity of the catalyst. Related or competing reactions The same catalysts and conditions that are used for hydrogenation reactions can also lead to isomerization of the alkenes fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 protecting th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sulfonic Acid
In organic chemistry, sulfonic acid (or sulphonic acid) refers to a member of the class of organosulfur compounds with the general formula , where R is an organic alkyl or aryl group and the group a sulfonyl hydroxide. As a substituent, it is known as a sulfo group. A sulfonic acid can be thought of as sulfuric acid with one hydroxyl group replaced by an organic substituent. The parent compound (with the organic substituent replaced by hydrogen) is the parent sulfonic acid, , a tautomer of sulfurous acid, . Salts or esters of sulfonic acids are called sulfonates. Preparation Aryl sulfonic acids are produced by the process of sulfonation. Usually the sulfonating agent is sulfur trioxide. A large scale application of this method is the production of alkylbenzenesulfonic acids: :RC6H5 + SO3 -> RC6H4SO3H In this reaction, sulfur trioxide is an electrophile and the arene is the nucleophile. The reaction is an example of electrophilic aromatic substitution. Alkylsulfonic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stilbene
Stilbene may refer to one of the two stereoisomers of 1,2-diphenylethene: * (''E'')-Stilbene (''trans'' isomer) * (''Z'')-Stilbene (''cis'' isomer) See also * Stilbenoid Stilbenoids are hydroxylated derivatives of stilbene. They have a C6–C2–C6 structure. In biochemical terms, they belong to the family of phenylpropanoids and share most of their biosynthesis pathway with chalcones. Most stilbenoids are prod ...s, a class of molecules found in plants * 1,1-Diphenylethylene {{Chemistry index ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salt (chemistry)
In chemistry, a salt is a chemical compound consisting of an ionic assembly of positively charged cations and negatively charged anions, which results in a compound with no net electric charge. A common example is Salt, table salt, with positively charged sodium ions and negatively charged chloride ions. The component ions in a salt compound can be either inorganic compound, inorganic, such as chloride (Cl−), or organic chemistry, organic, such as acetate (). Each ion can be either monatomic ion, monatomic, such as fluoride (F−), or polyatomic ion, polyatomic, such as sulfate (). Types of salt Salts can be classified in a variety of ways. Salts that produce hydroxide ions when dissolved in water are called ''alkali salts'' and salts that produce hydrogen ions when dissolved in water are called ''acid salts''. ''Neutral salts'' are those salts that are neither acidic nor basic. Zwitterions contain an anionic and a cationic centre in the same molecule, but are not considered s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
