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Alpha cleavage, (α-cleavage) in organic chemistry, refers to the act of breaking the carbon-carbon bond, adjacent to the carbon bearing a specified functional group.〔 〕 == Mass spectrometry == Generally this topic is discussed when covering tandem mass spectrometry fragmentation and occurs generally by the same mechanisms. For example of a mechanism of alpha cleavage, an electron is knocked off an atom (usually by electron collision) to form a radical cation. Electron removal generally happens in the following order: 1) lone pair electrons, 2) pi bond electrons, 3) sigma bond electrons. One of the lone pair electrons moves down to form a pi bond with an electron from an adjacent (alpha) bond. The other electron from the bond moves to an adjacent atom (not one adjacent to the lone pair atom) creating a radical. This creates a double bond adjacent to the lone pair atom (oxygen is a good example) and breaks/cleaves the bond from which the two electrons were removed. : In molecules containing carbonyl groups, alpha cleavage often competes with McLafferty rearrangement. 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「alpha cleavage」の詳細全文を読む スポンサード リンク
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