Safe Entry to Ag(I)/Ag(III) Mixed Valence Salts Containing the Homoleptic Ag(III) Anion [Ag(CF3)4]−

Abstract

AbstractThe synthesis of Naumann's AgI/AgIII mixed valence salt [AgI]+[AgIII(CF3)4]− (Ag‐1) is revisited. Ag‐1 is now safely available in half gram scale upon 2e− oxidation of AgF in presence of CF3SiMe3 and ambient air. In addition to its unprecedented crystallographic characterization, the use of Ag‐1 to build the novel AgI/AgIII salts [Ag(bpy)2]‐1, [Ag(18‐crown‐6)2]‐1, [Ag‐crypt‐222]‐1 and [Ag(PCy3)2]‐1 is herein reported, alongside their characterization by NMR, single crystal X‐ray diffraction (Sc‐XRD) and elemental analysis (EA). The utility of the currently affordable Ag‐1 in gold(I) catalysis was demonstrated by the excellent catalytic activity displayed by [{Au(PPh3)}2(μ‐Cl)]‐1 and [Au(PPh3)]‐1 in the 5‐exo‐dig cyclization of N‐propargylbenzamide (2). These cationic AuI catalysts are accessible from (PPh3)AuCl and Ag‐1, and outperform the activity of the well‐known benchmark catalyst (PPh3)AuNTf2.