Synthesis of Pentacyclic Framework of Herquline A
- 30 September 2021
- journal article
- research article
- Published by Wiley in Chemistry – An Asian Journal
- Vol. 16 (23), 3882-3885
- https://doi.org/10.1002/asia.202101004
Abstract
The highly strained bowl-shaped pentacyclic structure of herquline A has rendered it one of the most difficult problems in organic synthesis yet to be solved. The challenges associated with the synthesis of herquline A have been well documented in four Ph.D. dissertations and in multiple reports regarding syntheses of its structurally simpler congeners. Herein, we report the construction of the pentacyclic core of herquline A that contains both N10–C2 and C3–C3′ bonds. The key for success was the development of the tandem aza-Michael addition/enolate capture protocol that set the stage for subsequent palladium catalyzed C3(sp2)-C3′(sp2) coupling reaction. Ensuing oxidative dearomatization of the left aryl ring allowed the formation of the pentacyclic diketone core of herquline A.Keywords
Funding Information
- POSCO TJ Park Foundation
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