Total Synthesis of 2-Isocyanoallopupukeanane: Construction of Caged Skeleton by Intramolecular Alkylation of Bromonitriles

Org Lett. 2022 Sep 9;24(35):6407-6411. doi: 10.1021/acs.orglett.2c02434. Epub 2022 Aug 26.

Abstract

A new method for constructing the bicyclo[3.2.1]octane skeleton was developed by the intramolecular alkylation of a nitrile-side-chain-containing cyclohexanone derivative. The cyclization precursors were prepared via the stereoselective bromination of the triisopropylsilyl enol ethers of 4-substituted cyclohexanones. Upon treatment with LiNEt2, the bromonitriles underwent a stereoselective intramolecular SN2 reaction to afford bicyclo[3.2.1]octane derivatives with a cyano group on the convex face. The total synthesis of 2-isocyanoallopupukeanane (6.5% yield) from methyl vinyl ketone was accomplished via a 17-step transformation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alkylation
  • Cyclization
  • Molecular Structure
  • Octanes*
  • Skeleton*
  • Stereoisomerism

Substances

  • Octanes