Cross-Coupling of Primary Amides to Aryl and Heteroaryl Partners Using (DiMelHept~(CI))Pd Promoted by Trialkylboranes or B(C_6F_5)_3

摘要

Boron-derived Lewis acids have been shown to effectively promote the coupling of amide nucleophiles to a wide variety of oxidative addition partners using Pd-NHC catalysts. Through a combination of NMR spectroscopy and control studies with and without oxygen and radical scavengers, we propose that boron-imidates form under the basic reaction conditions that aid coordination of nitrogen to Pd(II), which is rate limiting, and directly delivers the intermediate for reductive elimination.