Transition-metal free, radical oxidation of 1,6-enyne cyclopropanation: synthesis of aza-bicyclo[4.1.0]heptane derivatives

Abstract

A straightforward transition-metal-free sustainable methodology for oxidative cyclopropanation of aza-1,6-enynes has been devised, enabling the synthesis of valuable, functionalized azabicyclo[4.1.0]heptane-2,4,5-triones, via four bond formation in a single step under mild conditions. Control experiments and real-time mass data monitoring using online ESI-MS spectroscopy support the pathway proposed for this reaction. The synthesized products have been utilized in diverse product transformations. Key advantages of this reaction include its operational ease, transition metal-free nature, rapid completion, and compatibility with a wide range of functional groups and substrates.