A Palladium-Catalyzed Carbo-oxygenation: The Bielschowskysin Case
نویسندگان
چکیده
An asymmetric synthesis of an advanced tetracyclic intermediate toward the synthesis of bielschowskysin (1) is described. A biomimetic [2 + 2]-photocyclization was used to establish the cyclobutane core of bielschowskysin. Macrocyclization under Heck conditions led to an unprecedented carbo-oxygenation of a 1,1-disubstituted double bond.
منابع مشابه
Use of a palladium(II)-catalyzed oxidative kinetic resolution in synthetic efforts toward bielschowskysin.
Progress toward the cyclobutane core of bielshowskysin is reported. The core was thought to arise from a cyclopropane intermediate via a furan-mediated cyclopropane fragmentation, followed by a 1,4-Michael addition. The synthesis of the cyclopropane intermediate utilizes a Suzuki coupling reaction, an esterification with 2-diazoacetoacetic acid, and a copper catalyzed cyclopropanation. An alcoh...
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