Intramolecular condensation via an o-quinone methide: total synthesis of (±)-heliol.
An acid-catalyzed intramolecular [4 + 2] cycloaddition of a non-natural bisabolene is reported. The key cyclocondensation was developed to access cyclic sesquiterpenes from linear phenolic precursors by generating a reactive o-quinone methide intermediate to initiate a cascade reaction. The new method was applied to the first total synthesis of (±)-heliol.
Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106, USA.
Jason C
JC
Green
Eric R
ER
Brown
Thomas R R
TR
Pettus
D002384:Catalysis; D003500:Cyclization; D045563:Indolequinones / Q000737:chemistry*; D015394:Molecular Structure; D012717:Sesquiterpenes / Q000138:chemical synthesis*
D045563:Indolequinones; D012717:Sesquiterpenes; C576138:heliol; C068040:quinone methide