DalPhos/Nickel-Catalyzed C2-H Arylation of 1,3-Azoles Using a Dual-Base System.

We report a versatile method for C2 functionalization of (benz)oxazoles and (benzo)thiazoles employing a tert -butylimino-tri(pyrrolidino)phosphorane/sodium trifluoroacetate (BTPP/NaTFA) "dual-base" system in combination with an air-stable Ni(II) precatalyst containing either CyPAd-DalPhos or PhPAd-DalPhos. These catalyst systems enable access to a reaction scope that encompasses a range of challenging oxidative addition partners, including (hetero)aryl chlorides as well as pivalates, tosylates, and other related phenol derivatives. The utility of this method is demonstrated through the derivatization of an active pharmaceutical ingredient and 5 mmol synthesis of a thiazole derivative.