Decorated Cyclopentadienes from Acetylene and Ketones in Just Two Steps
Elena Yu Schmidt1, Ivan A Bidusenko1, Igor' A Ushakov1
1A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch, Russian Academy of Sciences , 1 Favorsky Str., 664033 Irkutsk, Russia.
Abstract:
The products of the one-pot assembly of acetylene and ketones in the KOH/DMSO system, 7-methylene-6,8-dioxabicyclo[3.2.1]octanes, undergo an acid-catalyzed (CF3COOH, room temperature) rearrangement to rarely substituted cyclopentadienes in good-to-excellent yields. The mechanism of the rearrangement has been supported by the isolation and corresponding transformations of two intermediates.
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