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1-bromobutane
1-Bromobutane is the organobromine compound with the formula CH3(CH2)3Br. It is a colorless liquid, although impure samples appear yellowish. It is insoluble in water, but soluble in organic solvents. It is a primarily used as a source of the butyl group in organic synthesis. It is one of several isomers of butyl bromide. Synthesis Most 1-bromoalkanes are prepared by free-radical addition of hydrogen bromide to the 1-alkene. These conditions lead to the anti-Markovnikov addition, i.e. give the 1-bromo derivatives. 1-Bromobutane can also be prepared from butanol by treatment with hydrobromic acid: :CH3(CH2)3OH + HBr → CH3(CH2)3Br + H2O Reactions As a primary haloalkane, it is prone to SN2 type reactions. It is commonly used as an alkylating agent. When combined with magnesium metal in dry ether, it gives the corresponding Grignard reagent A Grignard reagent or Grignard compound is a chemical compound with the general formula , where X is a halogen and R is an organ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2-Bromobutane
2-Bromobutane is an isomer of 1-Bromobutane, 1-bromobutane. Both compounds share the molecular formula C4H9Br. 2-Bromobutane is also known as ''sec''-butyl bromide or methylethylbromomethane. Because it contains bromine, a halogen, it is part of a larger class of compounds known as alkyl halides. It is a colorless liquid with a pleasant odor. Because the carbon atom connected to the bromine is connected to two other carbons the molecule is referred to as a secondary alkyl halide. 2-Bromobutane is Chirality (chemistry), chiral and thus can be obtained as either of two Enantiomer, enantiomers designated as (''R'')-(−)-2-bromobutane and (''S'')-(+)-2-bromobutane. 2-Bromobutane is relatively stable, but is toxic and flammable. When treated with a strong base, it is prone to undergo an E2 reaction, which is a bimolecular elimination reaction, resulting in (predominantly) 2-butene, an alkene (double bond). 2-Bromobutane is an irritant, and harmful if ingested. It can irritate and b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
N-Butyllithium
''n''-Butyllithium C4H9Li (abbreviated ''n''-BuLi) is an organolithium reagent. It is widely used as a polymerization initiator in the production of elastomers such as polybutadiene or styrene-butadiene-styrene (SBS). Also, it is broadly employed as a strong base (superbase) in the synthesis of organic compounds as in the pharmaceutical industry. Butyllithium is commercially available as solutions (15%, 25%, 1.5 M, 2 M, 2.5 M, 10 M, etc.) in alkanes such as pentane, hexanes, and heptanes. Solutions in diethyl ether and THF can be prepared, but are not stable enough for storage. Annual worldwide production and consumption of butyllithium and other organolithium compounds is estimated at 2000 to 3000 tonnes. Although butyllithium is colorless, ''n''-butyllithium is usually encountered as a pale yellow solution in alkanes. Such solutions are stable indefinitely if properly stored,. but in practice, they degrade upon aging. Fine white precipitate (li ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
N-Propyl Bromide
1-Bromopropane (''n''-propylbromide or nPB) is an organobromine compound with the chemical formula CH3CH2CH2Br. It is a colorless liquid that is used as a solvent. It has a characteristic hydrocarbon odor. Its industrial applications increased dramatically in the 21st century due to the phasing out of chlorofluorocarbons, perchloroethylene, and chloroalkanes such as 1,1,1-Trichloroethane under the Montreal Protocol. Preparation Industrial routes to 1-bromopropane involve free-radical additions to the corresponding alkenes. In this way, the anti-Markovnikov product is obtained.David Ioffe, Arieh Kampf "Bromine, Organic Compounds" in Kirk-Othmer Encyclopedia of Chemical Technology 2002 by John Wiley & Sons. . A laboratory synthesis involves treating propanol with a mixture of hydrobromic and sulfuric acids: :CH3CH2CH2OH + HBr → CH3CH2CH2Br + H2O Alternate synthetic routes include treating propanol with phosphorus tribromide. or via a Hunsdiecker reaction with but ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrobromic Acid
Hydrobromic acid is a strong acid formed by dissolving the diatomic molecule hydrogen bromide (HBr) in water. "Constant boiling" hydrobromic acid is an aqueous solution that distills at and contains 47.6% HBr by mass, which is 8.77 mol/L. Hydrobromic acid has a p''K''a of −9, making it a stronger acid than hydrochloric acid, but not as strong as hydroiodic acid. Hydrobromic acid is one of the strongest mineral acids known. Uses Hydrobromic acid is mainly used for the production of inorganic bromides, especially the bromides of zinc, calcium, and sodium. It is a useful reagent for generating organobromine compounds. Certain ethers are cleaved with HBr. It also catalyzes alkylation reactions and the extraction of certain ores. Industrially significant organic compounds prepared from hydrobromic acid include allyl bromide, tetrabromobis(phenol), and bromoacetic acid. HBr almost uniquely participates in anti-Markovnikov hydrohalogenation of alkenes. The resulting 1-b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Springer-Verlag
Springer Science+Business Media, commonly known as Springer, is a German multinational publishing company of books, e-books and peer-reviewed journals in science, humanities, technical and medical (STM) publishing. Originally founded in 1842 in Berlin, it expanded internationally in the 1960s, and through mergers in the 1990s and a sale to venture capitalists it fused with Wolters Kluwer and eventually became part of Springer Nature in 2015. Springer has major offices in Berlin, Heidelberg, Dordrecht, and New York City. History Julius Springer founded Springer-Verlag in Berlin in 1842 and his son Ferdinand Springer grew it from a small firm of 4 employees into Germany's then second largest academic publisher with 65 staff in 1872.Chronology ". Springer Science+Business Media. In 1964, Springer expanded its business international ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grignard Reagent
A Grignard reagent or Grignard compound is a chemical compound with the general formula , where X is a halogen and R is an organic group, normally an alkyl or aryl. Two typical examples are methylmagnesium chloride and phenylmagnesium bromide . They are a subclass of the organomagnesium compounds. Grignard compounds are popular reagents in organic synthesis for creating new carbon-carbon bonds. For example, when reacted with another halogenated compound in the presence of a suitable catalyst, they typically yield and the magnesium halide as a byproduct; and the latter is insoluble in the solvents normally used. In this aspect, they are similar to organolithium reagents. Pure Grignard reagents are extremely reactive solids. They are normally handled as solutions in solvents such as diethyl ether or tetrahydrofuran; which are relatively stable as long as water is excluded. In such a medium, a Grignard reagent is invariably present as a complex with the magnesium atom co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diethyl Ether
Diethyl ether, or simply ether, is an organic compound in the ether class with the formula , sometimes abbreviated as (see Pseudoelement symbols). It is a colourless, highly volatile, sweet-smelling ("ethereal odour"), extremely flammable liquid. It is commonly used as a solvent in laboratories and as a starting fluid for some engines. It was formerly used as a general anesthetic, until non-flammable drugs were developed, such as halothane. It has been used as a recreational drug to cause intoxication. Production Most diethyl ether is produced as a byproduct of the vapor-phase hydration of ethylene to make ethanol. This process uses solid-supported phosphoric acid catalysts and can be adjusted to make more ether if the need arises. Vapor-phase dehydration of ethanol over some alumina catalysts can give diethyl ether yields of up to 95%. Diethyl ether can be prepared both in laboratories and on an industrial scale by the acid ether synthesis. Ethanol is mixed with a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnesium
Magnesium is a chemical element with the symbol Mg and atomic number 12. It is a shiny gray metal having a low density, low melting point and high chemical reactivity. Like the other alkaline earth metals (group 2 of the periodic table) it occurs naturally only in combination with other elements and it almost always has an oxidation state of +2. It reacts readily with air to form a thin passivation coating of magnesium oxide that inhibits further corrosion of the metal. The free metal burns with a brilliant-white light. The metal is obtained mainly by electrolysis of magnesium salts obtained from brine. It is less dense than aluminium and is used primarily as a component in strong and lightweight alloys that contain aluminium. In the cosmos, magnesium is produced in large, aging stars by the sequential addition of three helium nuclei to a carbon nucleus. When such stars explode as supernovas, much of the magnesium is expelled into the interstellar medium where it m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alkylating Agent
Alkylation is the transfer of an alkyl group from one molecule to another. The alkyl group may be transferred as an alkyl carbocation, a free radical, a carbanion, or a carbene (or their equivalents). Alkylating agents are reagents for effecting alkylation. Alkyl groups can also be removed in a process known as dealkylation. Alkylating agents are often classified according to their nucleophilic or electrophilic character. In oil refining contexts, alkylation refers to a particular alkylation of isobutane with olefins. For upgrading of petroleum, alkylation produces a premium blending stock for gasoline. In medicine, alkylation of DNA is used in chemotherapy to damage the DNA of cancer cells. Alkylation is accomplished with the class of drugs called alkylating antineoplastic agents. Nucleophilic alkylating agents Nucleophilic alkylating agents deliver the equivalent of an alkyl anion ( carbanion). The formal "alkyl anion" attacks an electrophile, forming a new covalent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SN2 Reaction
The SN2 reaction is a type of reaction mechanism that is common in organic chemistry. In this mechanism, one bond is broken and one bond is formed in a concerted way, i.e., in one step. The name SN2 refers to the Hughes-Ingold symbol of the mechanism: "SN" indicates that the reaction is a nucleophilic substitution, and "2" that it proceeds via a bi-molecular mechanism, which means both the reacting species are involved in the rate-determining step. The other major type of nucleophilic substitution is the SN1, but many other more specialized mechanisms describe substitution reactions. The SN2 reaction can be considered as an analogue of the associative substitution in the field of inorganic chemistry. Reaction mechanism The reaction most often occurs at an aliphatic sp3 carbon center with an electronegative, stable leaving group attached to it (often denoted X), which is frequently a halide atom. The breaking of the C–X bond and the formation of the new bond (often den ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haloalkane
The haloalkanes (also known as halogenoalkanes or alkyl halides) are alkanes containing one or more halogen substituents. They are a subset of the general class of halocarbons, although the distinction is not often made. Haloalkanes are widely used commercially. They are used as flame retardants, fire extinguishants, refrigerants, propellants, solvents, and pharmaceuticals. Subsequent to the widespread use in commerce, many halocarbons have also been shown to be serious pollutants and toxins. For example, the chlorofluorocarbons have been shown to lead to ozone depletion. Methyl bromide is a controversial fumigant. Only haloalkanes that contain chlorine, bromine, and iodine are a threat to the ozone layer, but fluorinated volatile haloalkanes in theory may have activity as greenhouse gases. Methyl iodide, a naturally occurring substance, however, does not have ozone-depleting properties and the United States Environmental Protection Agency has designated the compound a non-ozo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Butanol
Butanol (also called butyl alcohol) is a four-carbon alcohol with a formula of C4 H9 O H, which occurs in five isomeric structures (four structural isomers), from a straight-chain primary alcohol to a branched-chain tertiary alcohol; all are a butyl or isobutyl group linked to a hydroxyl group (sometimes represented as BuOH, ''n''-BuOH, ''i''-BuOH, and ''t''-BuOH). These are ''n''-butanol, 2 stereoisomers of sec-butanol, isobutanol and ''tert''-butanol. Butanol is primarily used as a solvent and as an intermediate in chemical synthesis, and may be used as a fuel. Biologically produced butanol is called biobutanol, which may be ''n''-butanol or isobutanol. Isomers The unmodified term ''butanol'' usually refers to the straight chain isomer with the alcohol functional group at the terminal carbon, which is also known as ''n''-butanol or 1-butanol. The straight chain isomer with the alcohol at an internal carbon is ''sec''-butanol or 2-butanol. The branched isomer with the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
