Copper-Catalyzed Ring-Opening (3+2) Annulation of Cyclopropenones with Ketoxime Acetates: Access to 1,2-Dihydro-pyrrol-3-ones Bearing a Quaternary Carbon Center

A Cu(I)-catalyzed ring-opening (3+2) annulation of cyclopropenones with ketoxime acetates has been developed. In disclosed protocol, ketoxime acetates are selected as C-N splicing unit to participate in the transformation process, furnishing a sequence of highly functional 1,2-dihydro-pyrrol-3-one derivatives in good isolated yields. Besides, scale-up reaction is conducted to demonstrate the practicability of developed methodology and a tentative mechanism for (3+2) annulation is also proposed.

Automated summary

A Cu(I)-catalyzed ring-opening (3+2) annulation of cyclopropenones with ketoxime acetates has been developed, leading to highly functional 1,2-dihydro-pyrrol-3-one derivatives in good isolated yields. The scalability of the reaction has been demonstrated, and a tentative mechanism for the (3+2) annulation has been proposed.