Intramolecular Diels–Alder reactions of cyclopentadiene systems: Model studies for the total synthesis of the capnellenes
- 1 March 1988
- journal article
- research article
- Published by Canadian Science Publishing in Canadian Journal of Chemistry
- Vol. 66 (3) , 439-448
- https://doi.org/10.1139/v88-077
Abstract
Model studies for a general intramolecular Diels–Alder approach to the tricyclo[6.3.0.02,6]undecene skeleton common to the capnellene marine sesquiterpenes are described. Suitably functionalized cyclopentadiene systems 14 and 21 were synthesized and their cycloaddition reactivity examined. Triene 14 cyclized to the tricyclic adducts 15 and 16. In contrast, the anticipated product 22 from intramolecular cycloaddition of triene 21 was not formed in isolatable yield. Instead the minor adduct (10% yield) possessed an exocyclic double bond and was assigned structure 30 based on its relative stability, as determined by MM2 type calculations, and nuclear magnetic resonance data. X-ray analysis established that the major adduct (40% yield) was a tetracyclic[6.3.1.01,6,01,10]dodecene system corresponding to 32, and which arose from competitive isomerization of the initial diene and cyclization via an exo transition state.This publication has 13 references indexed in Scilit:
- Synthesis of polyquinanes. 2. The total synthesis of (.+-.)-silphinene: the intramolecular Diels-Alder approachJournal of the American Chemical Society, 1985
- The IntramolecularDiels–Alder ReactionPublished by Wiley ,1984
- Total synthesis of the marine natural product .DELTA.9(12)-capnellene. Reversal of regiochemistry in the intramolecular 1,3-diyl trapping reactionJournal of the American Chemical Society, 1983
- Capnellane sesquiterpenes. Total synthesis of epiprecapnelladiene and Δ8(9)-capnelleneJournal of the Chemical Society, Perkin Transactions 1, 1982
- Consecutive Application of the α‐Alkynone Cyclization: Total Synthesis of (±)‐Δ9(12)‐CapnelleneHelvetica Chimica Acta, 1982
- Five-membered ring annulation via thermal rearrangement of β-cyclopropyl α,β-unsaturated ketones. A formal total synthesis of the sesquiterpenoid (±)-zizaeneCanadian Journal of Chemistry, 1982
- Total synthesis of (±)-Δ9(12)-capnellene via iterative intramolecular type-I-“Magnesium-ene” reactionsTetrahedron Letters, 1982
- Terpenoids—LXXII11For part LXXI, see Y.M. Sheikh, G. Singy, M. Kaisin, H. Eggert, C. Djerassi, B. Tursch, D. Daloze and J.C. Braekman, Tetrahedron 32, 1171 (1976).Tetrahedron, 1977
- Terpenoids—LXXITetrahedron, 1976
- CHEMISTRY OF COELENTERATES. III. OCCURRENCE OF ANTIMICROBIAL TERPENOID COMPOUNDS IN THE ZOOXANTHELLAE OF ALCYONARIANS*Transactions of the New York Academy of Sciences, 1962