石杉碱甲及其类似物吡啶稠合手性双环[3.3.1]壬烷骨架的不对称构建

A concise strategy for the enantioselective construction of the pyridine-fused chiral bicyclo[3.3.1]nonane skeleton of (+)-huperzine A and its nanlogues was reported. The key features of this strategy are the catalytic asymmetric hydrogenation of an exocyclic γ, δ-unsaturated β-ketoester via dynamic kinetic resolution combined with an intramolecular arylation as the key steps to constuct the pyridine-fused chiral bicyclo[3.3.1]nonane skeleton. This strategy provides a concise and rapid approach to the chiral core structure of huperzine A and its nanlogues from the known starting materials (5 steps and 17.4% overall yield).