Copper-Catalyzed Asymmetric 1,4-Aryl/Alkynylation of 1,3-Enynes to Access Axially Chiral Tetrasubstituted Allenes

The asymmetric 1,4-difunctionalization of 1,3-enynes represents a concise and highly efficient strategy for the preparation of chiral allenes. Herein, we developed a copper-catalyzed three-component asymmetric radical 1,4-aryl/alkynylation of 1,3-enynes by employing inexpensive, readily available, and highly reactive diaryliodonium salts as precursors to generate aryl radicals. The success of this reaction relied on the use of iminophenyl oxazolinylphenylamines (IPOPA) as chiral ligands. The reaction exhibited good compatibility with various alkynes, 1,3-enynes, and diaryliodonium salts, providing an effective method for constructing highly enantioselective tetrasubstituted axially chiral allene compounds.

Automated summary

We have developed a copper-catalyzed three-component asymmetric radical 1,4-aryl/alkynylation of 1,3-enynes using inexpensive and readily available diaryliodonium salts as precursors. The reaction relies on the use of IPOPA as chiral ligands to generate aryl radicals. This reaction exhibits good compatibility and provides an efficient method for constructing highly enantioselective tetrasubstituted axially chiral allene compounds.