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IX. Group Migration

  • Page ID
    23827
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    Acyl, silyl, phosphatoxy, phenyl, and cyano groups all are capable of undergoing group mi­gra­tion. Because in most reactions these groups are stable substituents and often act as protecting groups, migration is an event that depends not only on reaction conditions but also on the substrate having a particular type of structure. Sometimes it is unclear whether group migra­tion is an elementary reaction or a combination of elementary reactions. The silyl group migration pictured in Scheme 7 is thought to be an elementary reac­tion, but it is possible that this process consists of a pair of reactions, β‑frag­mentation and radical cyclization (Scheme 8).44 The group migration shown in eq 5945 appeared at first to be an elementary reaction, but extensive investigation has shown that it consisted of heterolytic fragmentation followed by ionic recombin­ation (Scheme 9).46–48

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    This page titled IX. Group Migration is shared under a All Rights Reserved (used with permission) license and was authored, remixed, and/or curated by Roger W. Binkley and Edith R. Binkley.

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