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Butyllithium
Butyllithium may refer to one of 5 isomeric organolithium reagents of which 3 are commonly used in chemical synthesis: * ''n''-Butyllithium, abbreviated BuLi or nBuLi * ''sec''-Butyllithium, abbreviated ''sec''-BuLi or sBuLi, has 2 stereoisomers, but is commonly used as racemate *isobutyllithium * ''tert''-Butyllithium, abbreviated ''tert''-BuLi or tBuLi {{Chemistry index ... [...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 (l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sec-Butyllithium
''sec''-Butyllithium is an organometallic compound with the formula CH3CHLiCH2CH3, abbreviated ''sec''-BuLi or ''s''-BuLi. This chiral organolithium reagent is used as a source of ''sec''-butyl carbanion in organic synthesis.. Synthesis ''sec''-BuLi can be prepared by the reaction of ''sec''-butyl halides with lithium metal: Properties Physical properties ''sec''-Butyllithium is a colorless viscous liquid. Using mass spectrometry, it was determined that the pure compound has a tetrameric structure. It also exists as tetramers when dissolved in organic solvents such as benzene, cyclohexane or cyclopentane. The cyclopentane solution has been detected with 6Li-NMR spectroscopy to have a hexameric structure at temperatures below −41 °C. In electron-donating solvents such as tetrahydrofuran, there exists an equilibrium between monomeric and dimeric forms. Chemical properties The carbon-lithium bond is highly polar, rendering the carbon basic, as in other organolithium reag ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
