Intramolecular Amido Transfer Leading to Structurally Diverse Nitrogen-Containing Macrocycles

Reported herein is the development of rhodium-catalyzed intramolecular amido transfer as an efficient route to nitrogen-containing macrocycles starting from acetophenone ketoximes tethered with either aryl or alkyl azides. Facile generation of rhodacycles and metal imido intermediates was the key to success in this mechanistic scaffold to represent the first example of an intramolecular inner-sphere C-H amination. While substrates bearing aryl azides underwent a monomeric ring formation in high yields, a dimeric double cyclization took place exclusively with alkyl-azide-tethered ketoximes, thus affording up to 36-membered azamacrocyclic products.