<scp>Palladium‐Catalyzed</scp> [4 + 4] Cycloaddition of <scp>Homo‐TMM All‐Carbon</scp> 1,<scp>4‐Dipole</scp> Precursors for Construction of Benzofuro[3,2‐<i>b</i>]azocines and Furo[3,2‐<i>b</i>]azocines

Abstract

Comprehensive Summary We developed a novel Pd‐catalyzed [4 + 4] cycloaddition of (benzo)furan‐derived azadienes with homo‐TMM all‐carbon 1,4‐dipoles in situ generated from α ‐allyl malonate derivatives, affording an array of benzofuro[3,2‐ b ]azocines and furo[3,2‐ b ]azocines with good to excellent yields (up to 96%) and exclusive regioselectivities. This methodology featured mild reaction conditions and good functional group tolerance. The synthetic utility was demonstrated by a gram‐scale reaction. Furthermore, the catalytic asymmetric [4 + 4] cycloaddition version has also been explored.

Topics & Concepts