Ni(II) Precatalysts Enable Thioetherification of (Hetero)Aryl Halides and Tosylates and Tandem C-S/C-N Couplings

Ni-catalyzed C-S cross-coupling reactions have received less attention compared with other C-heteroatom couplings. Most reported examples comprise the thioetherification of most reactive aryl iodides with aromatic thiols. The use of C-O electrophiles in this context is almost uncharted. Here, we describe that preformed Ni(II) precatalysts of the type NiCl(allyl)(PMe2Ar') (Ar'=terphenyl group) efficiently couple a wide range of (hetero)aryl halides, including challenging aryl chlorides, with a variety of aromatic and aliphatic thiols. Aryl and alkenyl tosylates are also well tolerated, demonstrating, for the first time, to be competent electrophilic partners in Ni-catalyzed C-S bond formation. The chemoselective functionalization of the C-I bond in the presence of a C-Cl bond allows for designing site-selective tandem C-S/C-N couplings. The formation of the two C-heteroatom bonds takes place in a single operation and represents a rare example of dual electrophile/nucleophile chemoselective process.

Automated summary

This study describes a new Ni-catalyzed C-S cross-coupling reaction that efficiently couples a wide range of (hetero)aryl halides, including challenging aryl chlorides, with various aromatic and aliphatic thiols. Additionally, it was found that aryl and alkenyl tosylates can also serve as competent electrophilic partners in the reaction.