Convergent Access to Polycyclic Cyclopentanoids from α,β-Unsaturated Acid Chlorides and Alkynes through a Reductive Coupling, Nazarov Cyclization Sequence

Reductive coupling of α,β-unsaturated acid chlorides A with alkynoyls B provides convergent access to Nazarov cyclization precursors, α-carboxy divinyl ketones C. Cyclization of C gives an intermediate oxyallyl cation intermediate D, which can be trapped with tethered arenes (Ar). The resultant products can be further cyclized through nucleophilic displacement of suitable leaving groups X by tethered OH groups to give lactones (in a subsequent step). Where X is a suitable chiral auxiliary (e.g., oxazolidinone) this strategy affords access to homochiral cyclopentanoids.

α,β-不饱和酰氯A与炔酰类化合物B的还原偶联反应，可通过汇聚式合成路径便捷获取Nazarov环化（Nazarov cyclization）前体——α-羧基二乙烯基酮C。化合物C经环化得到氧烯丙基正离子中间体D，该中间体可被锚连芳环（Ar）捕获。所得产物可通过锚连羟基（OH）对合适离去基团X的亲核取代进一步环化，于后续步骤中得到内酯类产物。若X为合适的手性助剂（如恶唑烷酮（oxazolidinone）），该策略可用于制备手性纯环戊烷类化合物。