A stereoselective intramolecular cyclopropanation via a de novo class of push–pull carbenes derived from DMDO-epoxidations of chiral ynamides

This work describes the first examples of diastereoselective intramolecular cyclopropanations of a de novo class of push-pull carbenes derived from DMDO-epoxidations of chiral ynamides. This reaction sequence essentially constitutes a tandem epoxidation-cyclopropanation that effectively gives arise to a series of structurally unique amido-cyclopropanes. A plausible mechanistic model is proposed revealing insights into this novel cyclopropanation process.