Convergent access to polycyclic cyclopentanoids from α,β-unsaturated acid chlorides and alkynes through a reductive
Jason H Chaplin1, Kristal Jackson, Jonathan M White
1Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University , 381 Royal Parade, Parkville, Victoria 3052, Australia.
Abstract:
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.
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