Competent partners: π-Allyl–nickel precatalysts supported by dialkylterphenyl phosphines efficiently couple a wide range of electrophiles including aryl iodides/bromides/chlorides and, for the first time, aryl and alkenyl tosylates with aromatic and aliphatic thiols. In addition, tandem C−S and C−N coupling of multi-electrophile/nucleophile combinations is achieved in a completely chemoselective manner leading to highly functionalized products. More information can be found in the Full Paper by A. Prieto, M. C. Nicasio, et al. (DOI: 10.1002/chem.202101906).

In this study, three new terphenyl-substituted NPN ligands bearing pyridyl groups, two phosphonites and one diaminophosphine, were synthesized and fully characterized. Their coordination chemistry with copper(I) was investigated using CuBr and [Cu(NCMe)₄]PF₆ as metal precursors, affording six mononuclear Cu(I) complexes, which were characterized using NMR spectroscopy and, in selected cases, single-crystal X-ray diffraction (SCXRD) analysis. The NPN ligands adopt a κ³-coordination mode, stabilizing the copper centers in distorted tetrahedral geometries. The catalytic performance of these complexes in the S-arylation of thiols with aryl iodides was evaluated. Under optimized conditions, complexes 2a and 2b exhibited excellent activity and broad substrate scope, tolerating both electron-donating and electron-withdrawing groups, as well as sterically hindered and heteroaryl substrates. The methodology also proved effective for aliphatic thiols and demonstrated high chemoselectivity in the presence of potentially reactive functional groups. In contrast, aryl bromides and chlorides were poorly reactive under the same conditions. These findings highlight the potential of well-defined Cu(I)–NPN complexes as efficient and versatile precatalysts for C–S bond formation.