posted on 2020-03-17, 21:29authored byHuaiyuan Hu, Ashley M. Gilliam, Fengrui Qu, Kevin H. Shaughnessy
Enolizable
ketones have been identified as effective activators
for palladium(II) precatalysts in the coupling of aryl bromides and
aniline. N-arylation reactions catalyzed by [(DTBNpP)PdCl2]2 (DTBNpP = (bis(tert-butyl)neopentylphosphine)
and PEPPSI-IPr precatalysts are activated by the addition of acetone,
mesityl oxide, and 3-pentanone. 3-Pentanone was the most effective
activator. Mechanistic studies show that acetone, 3-pentanone, and
mesityl oxide reduce [(DTBNpP)PdCl2]2 in the
presence of NaO-t-Bu to Pd0(DTBNpP)2.