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. 2022 Jan 12;144(1):118-122.
doi: 10.1021/jacs.1c12283. Epub 2021 Dec 27.

A Concise Enantioselective Approach to Quassinoids

William P Thomas  1 , Sergey V Pronin  1
Affiliations

A Concise Enantioselective Approach to Quassinoids

William P Thomas et al. J Am Chem Soc. .

Abstract

A synthetic approach to quassinoids is described. The route to the tetracyclic core relies on an efficient and selective annulation between two unsaturated carbonyl components that is initiated by catalytic hydrogen atom transfer from an iron hydride to an alkene. Application of this strategy allows for enantioselective synthesis of quassin, which is prepared in 14 steps from commercially available starting material.

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Conflict of interest statement

The authors declare no competing financial interest.

Figures

Figure 1.
Figure 1.
Representative quassinoids and our approach to the common polycyclic motif.
Scheme 1.
Scheme 1.
Synthesis of γ,δ-Unsaturated Aldehyde 4
Scheme 2.
Scheme 2.
Synthesis of Epoxyquinone 8
Scheme 3.
Scheme 3.
Synthesis of (+)-Quassin (1)
See this image and copyright information in PMC

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