Total synthesis of (+/-)-taiwaniaquinol B via a domino intramolecular friedel-crafts acylation/carbonyl alpha-tert-alkylation reaction.
The first synthesis of taiwaniaquinol B, a 6-nor-5(6-->7)abeoabietane-type diterpenoid exhibiting the uncommon fused 6-5-6 tricyclic carbon skeleton, was accomplished in 15 steps. A Lewis acid-promoted tandem intramolecular Friedel-Crafts/carbonyl alpha-tert-alkylation reaction was exploited as the core strategy for the synthesis of the sterically congested 1-indanone-containing tricyclic structure. This multiple carbon-carbon bond forming reaction exploits the unique reactivity of Meldrum's acid. The facile precursor synthesis makes this a useful methodology for the expedient modification and assembly of sterically congested 1-indanone-containing ring systems.
Fillion
Eric
E
Department of Chemistry, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1. efillion@uwaterloo.ca
Fishlock
Dan
D
D000215:Acylation; D000478:Alkylation; D032485:Cryptomeria / Q000737:chemistry*; D004224:Diterpenes / Q000138:chemical synthesis*; D008968:Molecular Conformation; D013237:Stereoisomerism; D013624:Taiwan
D004224:Diterpenes; C505702:taiwaniaquinol B