ChemInform Abstract: Synthetic Studies on Indoles and Related Compounds. Part 45. A New Route for the Tricyclic Indole System: A Useful Intermediate for Ergot Alkaloids.

✍ Scribed by Y. YOKOYAMA; H. MATSUSHIMA; M. TAKASHIMA; T. SUZUKI; Y. MURAKAMI

• Publisher: John Wiley and Sons
• Year: 2010
• Weight: 41 KB
• Volume: 29
• Category: Article
• ISSN: 0931-7597
• DOI: 10.1002/chin.199819043

✦ Synopsis

Synthetic Studies on Indoles and Related Compounds. Part 45. A New Route for the Tricyclic Indole System: A Useful Intermediate for Ergot Alkaloids.

-4-Bromoindole derivatives bearing α,β-unsaturated esters or aldehydes in the C 3 -side chain [cf. (IV), (VI), (IX)] are prepared and subjected to intramolecular Pd-catalyzed cyclization (Heck reaction) and radical induced cyclization reactions. Interestingly, the course of the reaction depends on the length of the side chain and the method used to achieve the cyclization. A cyclohepta [c,d]indole system [cf. (V)] is obtained using the Heck reaction, while a cyclohexa [c,d]indole system is formed by the radical reaction [cf. (VII), (X)].