Seven‐ and Eight‐Membered Carbocycles

Ynol Ethers as Ketene Equivalents in Rhodium-Catalyzed Intermolecular [5 + 2] Cycloaddition Reactions

“…In contrast, ynol ethers are electron-rich and easily prepared by alkylation of the parent metal alkoxyacetylide . However, their use in metal-catalyzed cycloadditions is largely unexplored and potentially problematic due to their reported “instability” in the presence of cationic rhodium complexes. , Beyond their mechanistic interest, the study of ynol ethers as 2C components in [5 + 2] cycloadditions is further motivated by the potential use of such a process in accessing diverse targets. , Numerous natural (estimated at >3000) and non-natural products, including many of research and therapeutic importance, incorporate functionalities derivable from cycloheptan-1,4-diones (CHDs). , Yet few methods exist for the direct construction of such systems . We have now found that the metal-catalyzed cycloaddition of ynol ethers and VCPs provides a solution to this problem.…”