A Barbier reaction-Heck arylation sequence from α-bromomethylbutenolide to fused tri and tetracyclic lactones has been developed. The first step involving a Barbier reaction enabled installing -bromoaromatics in α-ylidene γ-lactones. The latter substrates were subjected to intramolecular Heck reaction conditions which selectively afforded 6,5,5 or 6,6,5 fused ring systems depending on the nature of the base employed.

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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6149967PMC
http://dx.doi.org/10.3390/molecules22122171DOI Listing

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