Affordable Access

Publisher Website

Studies toward the total synthesis of di- and sesterterpenes with a dicyclopenta[a,d]cyclooctane skeleton. Construction of a versatile A/B ring building block via a ring-closing metathesis reaction and carbocationic rearrangement

Authors
Journal
Tetrahedron Letters
0040-4039
Publisher
Elsevier
Publication Date
Volume
46
Issue
7
Identifiers
DOI: 10.1016/j.tetlet.2004.12.077
Keywords
  • Terpenoids
  • Total Synthesis
  • Mukaiyama Reaction
  • Tsuji Alkylation
  • Ring-Closing Metathesis
  • Carbocationic Rearrangements

Abstract

Abstract The cyclopentacyclooctane derivative 1 , chosen as the key building block in a synthesis of terpenoid ophiobolates and fusicoccins, has been prepared from 2-methylcyclo-pent-2-en-1-one 5 . Cyclization of the intermediate 1,9-diene of l, u configuration 10 under metathesis conditions (Grubbs’ catalyst 15 ) afforded the eight-membered ring product 13 , whereas cyclization of the l, l diastereomer 9 produced a seven-membered ring analog 12 . Cationic rearrangement of epoxide 26 occurred with methyl group migration to give ketone 27 as the major product.

There are no comments yet on this publication. Be the first to share your thoughts.