Asymmetric access to β-funebrene via a trans-selective annulation of allenylsilane-enes

The construction of trans-fused 5/5 ring systems constitutes a substantial challenge because of their highly strained scaffolds. In this issue of Chem, Li and co-workers present an intramolecular [3 + 2] annulation reaction of allenylsilane-enes, leading to the efficient preparation of multi-functionalized trans-fused 5/5 rings and a concise asymmetric total synthesis of (+)-β-funebrene. The construction of trans-fused 5/5 ring systems constitutes a substantial challenge because of their highly strained scaffolds. In this issue of Chem, Li and co-workers present an intramolecular [3 + 2] annulation reaction of allenylsilane-enes, leading to the efficient preparation of multi-functionalized trans-fused 5/5 rings and a concise asymmetric total synthesis of (+)-β-funebrene. Intramolecular [3 + 2] annulation of allenylsilane-enes: Direct synthesis of highly strained trans-fused 5/5 ring systemsLv et al.ChemSeptember 15, 2023In BriefThe asymmetric total synthesis of β-funebrene, containing a highly strained trans-fused 5/5 ring system, has been achieved. The synthetically challenging, multi-functionalized trans-fused 5/5 ring systems were diastereoselectively and efficiently constructed by the first intramolecular [3 + 2] annulation reaction of allenylsilane-enes. This is the first stereoselective means for the direct synthesis of trans-fused 5/5 ring systems from acyclic precursors. Thus, this approach could be extended to the total synthesis of other bioactive molecules with such ring systems, expanding the horizons of biological research. Full-Text PDF