As diacyl olefin derivatives are known to be very reactive toward nucleophiles, and those with Z-configuration seem easy to change into E-isomers, we planned to protect the olefin part as a Diels-Alder adduct with cyclopentadiene and to regenerate it by retro Diels-Alder reaction at a final stage. Thus the enone L which is easily obtained by Dieis-Aider reaction of p-quinone with cyclopentadiene was chosen as a starting material. Triethylamine ...
[Alder; Stein Justus Liebigs Annalen der Chemie, 1931 , vol. 485, p. 215 Justus Liebigs Annalen der Chemie, 1933 , vol. 501, p. 253 Full Text Show Details Diels; Alder Justus Liebigs Annalen der Chemie, 1928 , vol. 460, p. 98 Justus Liebigs Annalen der Chemie, 1930 , vol. 478, p. 141]