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The Grignard reaction (pronounced ) is an organometallic chemical reaction in which alkyl, vinyl, or aryl-magnesium halides (Grignard reagents) add to a carbonyl group in an aldehyde or ketone.〔(Chapter 19: Carboxylic Acids ). Organic Chemistry 4e Carey. mhhe.com〕 This reaction is an important tool for the formation of carbon–carbon bonds. The reaction of an organic halide with magnesium is ''not'' a Grignard reaction, but provides a Grignard reagent.〔IUPAC. Compendium of Chemical Terminology, 2nd ed. (the "Gold Book"). Compiled by A. D. McNaught and A. Wilkinson. Blackwell Scientific Publications, Oxford (1997). ISBN 0-9678550-9-8. .〕 : Grignard reactions and reagents were discovered by and are named after the French chemist François Auguste Victor Grignard (University of Nancy, France), who was awarded the 1912 Nobel Prize in Chemistry for this work. Grignard reagents are similar to organolithium reagents because both are strong nucleophiles that can form new carbon–carbon bonds. ==Reaction mechanism== The Grignard reagent functions as a nucleophile, attacking the electrophilic carbon atom that is present within the polar bond of a carbonyl group. The addition of the Grignard reagent to the carbonyl typically proceeds through a six-membered ring transition state. However, with hindered Grignard reagents, the reaction may proceed by single-electron transfer. Similar pathways are assumed for other reactions of Grignard reagents, e.g., in the formation of carbon–phosphorus, carbon–tin, carbon–silicon, carbon–boron and other carbon–heteroatom bonds. 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「Grignard reaction」の詳細全文を読む スポンサード リンク
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