Platinum-Catalyzed Enantioselective Tandem Alkylation/Arylation Phosphines. Asymmetric Synthesis of Primary P-Stereogenic 1-Phosphaacenaphthenes

Enantioselective tandem alkylation/arylation of primary phosphines with 1-bromo-8-chloromethyl naphthalene catalyzed by Pt(DuPhos) complexes gave P-stereogenic 1-phosphaacenaphthenes (AcePhos) in up to 74% ee. Diastereoselective formation of four P-C bonds in one pot with bis(primary) phosphines gave C-2-symmetric diphosphines, including the o-phenylene derivative DuAcePhos, for which the rac isomer was formed with high enantioselectivity. These reactions, which appear to proceed via an unusual metal-mediated nucleophilic aromatic substitution pathway, yield a new class of heterocycles with potential applications in asymmetric catalysis.