Homoleptic Phosphaalkyne Complexes of Silver(I)

Abstract

By employing silver salts with a weakly coordinating anion Ag[A] ([A]=[FAl{OC12F15}3], [Al{OC(CF3)3}4]), two phosphaalkynes could be coordinated side‐on to a bare silver(I) center to form the unprecedented homoleptic complexes [Ag(η2‐P≡CtBu)2][FAl{OC12F15}3] (1) and [Ag(η2‐P≡CtBu)2][Al{OC(CF3)3}4] (2). DFT calculations show that the perpendicular arrangement in 1 is the minimum energy structure of the coordination of the two phosphaalkynes to a silver atom, whereas for 2 a unique square‐planar coordination mode of the phosphaalkynes at Ag+ was found. Reactions with donor molecules yield the trigonally planar coordinated silver salts [((CH3)2CO)Ag(η2‐P≡CtBu)2][FAl{OC12F15}3] (3) and [(C7H8)2Ag(η2‐P≡CtBu)][FAl{OC12F15}3] (4). All of the compounds were comprehensively characterized in solution and in the solid state.