The gold-catalyzed reaction between benzofuroxans, functioning as nitrene transfer reagents, and N-allylynamides leads to 3-azabicyclo[3.1.0]hexan-2-imines. This highly selective annulation proceeds smoothly under mild conditions (5 mol % Ph3PAuNTf2, PhCl, 60 °C) and exhibits high functional group tolerance (21 examples, ≤96% yields). The obtained cyclopropanated products represent a useful synthetic platform with an easily modulated substitution pattern as illustrated by their postmodifications. Intramolecular cyclopropanation of gold α-imino carbene intermediates is suggested as a key step of the catalytic cycle.
Shcherbakov, N. V., Dar’In, D. V., Kukushkin, V. Y., & Dubovtsev, A. Y. (2021). Gold-Catalyzed Nitrene Transfer from Benzofuroxans to N-Allylynamides: Synthesis of 3-Azabicyclo[3.1.0]hexanes. Journal of Organic Chemistry, 86(18), 12964–12972. https://doi.org/10.1021/acs.joc.1c01654