In Situ Formation of Cationic π-Allylpalladium Precatalysts in Alcoholic Solvents: Application to C–N Bond Formation

• DOI: 10.1021/acscatal.1c04641
• Publication Date: 2021-12-20T20:13:36Z
• Authors: Philippe Steinsoultz; Aurélien Bailly; Patrick Wagner; Estefania Oliva; Martine Schmitt; Laurence Grimaud; Frédéric Bihel
• Keywords: Cationic polymerization; Coupling reaction

We report an efficient Buchwald–Hartwig cross-coupling reaction in alcoholic solvent, which a low catalyst loading showed excellent performance for coupling aryl halides (I, Br, and Cl) with broad set of amines, amides, ureas, carbamates under mild conditions. Mechanistically speaking, protic polar medium, extremely bulky biarylphosphine ligands interact the dimeric precatalyst [Pd(π-(R)-allyl)Cl]2 to form corresponding cationic complexes [Pd(π-(R)-allyl)(L)]Cl situ spontaneously. The resulting further evolves basic conditions into L-Pd(0) catalyst, is commonly employed reactions. This mechanistic study highlights prominent role solvents formation active catalyst.