Nickel‐ and Palladium‐Catalyzed Cross‐Coupling Reactions of Organostibines with Organoboronic Acids

A strategy for the formation of antimony-carbon bond was developed by nickel-catalyzed cross-coupling of halostibines. This method has been applied to the synthesis of various triaryl- and diarylalkylstibines from the corresponding cyclic and acyclic halostibines. This protocol showed a wide substrate scope (72 examples) and was compatible to a wide range of functional groups such as aldehyde, ketone, alkene, alkyne, haloarenes (F, Cl, Br, I), and heteroarenes. A successful synthesis of arylated stibine 3 a in a scale of 34.77 g demonstrates high synthetic potential of this transformation. The formed stibines (R3Sb) were then used for the palladium-catalyzed carbon-carbon bond forming reaction with aryl boronic acids [R-B(OH)(2)], giving biaryls with high selectivity, even the structures of two organomoieties (R and R ') are very similar. Plausible catalytic pathways were proposed based on control experiments.