Synfacts 2021; 17(03): 0237
DOI: 10.1055/s-0040-1720298
Synthesis of Natural Products and Potential Drugs

Total Synthesis of (–)-Berkelic Acid

Contributor(s):
Erick M. Carreira
,
Moritz J. Classen
Cheng H.-G, Yang Z, Chen R, Cao L, Tong W.-Y, Wei Q, Wang Q, Wu C, Qu S, *, Zhou Q. * Wuhan University and Hunan University, Changsha, P. R. of China
A Concise Total Synthesis of (–)-Berkelic Acid.

Angew. Chem. Int. Ed. 2021;
DOI: 10.1002/anie.202014660.
 

Significance

Qu, Zhou, and co-workers report a concise total synthesis of (–)-berkelic acid, which was isolated in 2006 from an extremophilic Penicillium species. Their synthesis relies on a Catellani ­reaction followed by an oxa-Michael addition performed in a one-pot operation and a late-stage Ni-catalyzed reductive coupling.


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Comment

The synthesis commences with the preparation of enone B, which is accessed from ­ketone A in four steps. A Catellani reaction/oxa-­Michael cascade gives rise to F. Benzyl deprotection followed by spiroacetalization gives ketal G in good yield and excellent diastereoselectivity, setting four stereocenters from only one existing chiral center. Iodide H is then coupled with acid chloride J in a Ni-catalyzed reductive coupling to give methyl ester K. (–)-Berkelic acid is obtained by selective saponification in the presence of (Bu3Sn)2O.


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Publication History

Publication Date:
16 February 2021 (online)

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