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Synlett 2022; 33(06): 589-583
DOI: 10.1055/s-0041-1737334
letter

Highly Stereoselective Formation of a Spiro Center by a 1,4-Addition/Elimination Reaction of 3,5-Difluorocyclohexa-2,5-dienones

Masao Morita∗
a   Research Foundation ITSUU Laboratory, C1232 Kanagawa Science Park R and D Building, Takatu-ku, Kawasaki 213-0012, Japan
,
Hiroaki Kurouchi
a   Research Foundation ITSUU Laboratory, C1232 Kanagawa Science Park R and D Building, Takatu-ku, Kawasaki 213-0012, Japan
,
Nobuaki Nemoto
b   JEOL RESONANCE Inc., Musashino, Akishima, Tokyo 196-8558, Japan
› Author AffiliationsThis work was generously supported by funding from the Research Foundation ITSUU Laboratory.
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Abstract

Spirocyclic 3,5-difluorocyclohexa-2,5-dienones possessing a triisopropylsiloxy-containing cyclic ether appendage were synthesized by oxidative dearomatization of the corresponding phenols. By group selectivity in the nucleophilic 1,4-addition/elimination reaction, highly stereoselective formation of the spiro center was successfully achieved. This reaction might provide access to total syntheses of (+)-bisdechlorogeodin and (+)-geodin with complete control of the formation of the spirocyclic structure.

Key words

spiro compounds - addition reaction - elimination reaction - stereoselectivity

Supporting Information

    Supporting information for this article is available online at https://doi.org/10.1055/s-0041-1737334.
  • Supporting Information


Publication History

Received: 22 November 2021

Accepted after revision: 29 December 2021

Article published online:
27 January 2022

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