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43.8.2.3.3 Method 3: Base-Catalyzed Rearrangement of Internal Alkynes

DOI: 10.1055/sos-SD-043-00415

Krueger, A.Science of Synthesis, (200843506.

In the case of functionalized or branched internal alkynes, the rearrangement to isomeric internal alkynes can be used preparatively as well. Branching hinders the migration of the triple bond to the terminal carbon atom owing to the lack of the necessary proton at the branching points (see also Section 43.8.2.3.2).[‌150‌] Some functional groups, such as carboxy and ester groups, also favor the formation of internal isomers. Usually, the triple bond migrates away from electron-withdrawing groups.[‌145‌]

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