A New General Method for the Construction of Angular Triquinanes from 4-Allylcyclobutenones. Rearrangement of Linear Triquinanes to the Angular Isomers
Rearrangements of Linear Triquinanes to the Angular Isomers
摘要:
Warming substituted linear triquinanes in t-BuOK/t-BuOH resulted in their isomerization to the corresponding angularly fused isomers in good yield (59-84%). An alternate route employs a base-catalyzed intramolecular Michael addition of bicyclo[6.3.0]undecenediones, a class of compounds found to be readily-available from 1-alkenylbicyclo[3.2.0]hepten-7-ones via a "one-pot" sequence of reactions. This method is complementary to the isomerization reaction since it provides access to angular triquinanes not readily available from their linear isomers.