ChemInform Abstract: Cobalt- Catalyzed [4 + 2 + 2] Cycloadditions of Bicyclo[2.2.2]octadienes.

✍ Scribed by Rattana Kiattansakul; John K. Snyder

• Publisher: John Wiley and Sons
• Year: 2010
• Weight: 35 KB
• Volume: 30
• Category: Article
• ISSN: 0931-7597
• DOI: 10.1002/chin.199922086

✦ Synopsis

Cobalt-Catalyzed [4 + 2 + 2] Cycloadditions of Bicyclo[2.2.2]octadienes.

-Norbornadiene (I) and the benzobarrelenes (IV) undergo cobalt-catalyzed [4 + 2 + 2] cycloaddition with the dienes (II) or (VI) to give the corresponding adducts. In contrast, analogous reaction of the bicyclo[3.2.1]octadeine (VIII) affords only the [4 + 2] adduct in low yield. Benzobarrelene (IVa) also produces the [2 + 2 + 2] adduct (XII). Nickon opening of the cyclopropyl ring in (Va) forms (XIV) as the kinetic product, which rearranges to the thermodynamic product (XV) (