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A Gilman reagent is a lithium and copper (diorganocopper) reagent compound, R2CuLi, where R is an organic radical. These are useful because they react with organic chlorides, bromides, and iodides to replace the halide group with an R group. This is extremely useful in creating larger molecules from smaller ones. These reagents were discovered by Henry Gilman. Lithium dimethylcopper (CH3)2CuLi can be prepared by adding copper(I) iodide to methyllithium in tetrahydrofuran at −78 °C. In the reaction depicted below,〔''Modern Organocopper Chemistry, '' N. Krause Ed. Wiley-VCH, 2002.〕 the Gilman reagent is a methylating reagent reacting with an alkyne in a conjugate addition, and the negative charge is trapped in a nucleophilic acyl substitution with the ester group forming a cyclic enone. Gilman reagents have complicated structures in crystalline form and in solution. Lithium dimethylcuprate is a dimer in diethyl ether forming an 8-membered ring with two lithium atoms coordinating between two methyl groups. Similarly, lithium diphenylcuprate forms a dimeric etherate, ()2, in the solid state. If the Li+ ions are rendered inert by complexation with the crown ether 12-crown-4, the isolated diorganylcuprate anions that remain adopt a linear coordination geometry at copper. ==See also== * Organolithium reagent * Organocopper * Grignard reagent 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「Gilman reagent」の詳細全文を読む スポンサード リンク
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