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|Section2= |Section3= |Section7= |Section8= }} ''n''-Butyllithium (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%, 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 1800 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 (lithium hydride) is deposited and the color changes to orange.〔http://www.sigmaaldrich.com/catalog/product/fluka/20160?lang=en®ion=GB〕〔 ==Structure and bonding== (詳細はcyclohexane). The cluster is a distorted cubane structure with Li and ''C''H2R groups at alternating vertices. An equivalent description describes the tetramer as a Li4 tetrahedron interpenetrated with a tetrahedron ()4. Bonding within the cluster is related to that used to describe diborane, but more complex since eight atoms are involved. Reflecting its "electron-deficient character," ''n''-butyllithium is highly reactive toward Lewis bases. Due to the large difference between the electronegativities of carbon (2.55) and lithium (0.98), the C-Li bond is highly polarized. The charge separation has been estimated to be 55-95%. For practical purposes, n-BuLi can often be considered to react as the butyl anion, ''n''-Bu−, and a lithium cation, Li+. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「N-Butyllithium」の詳細全文を読む スポンサード リンク
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