Organyltriphenylphosphonium Dicyanoargentates [Ph3PCH2СH=CHCH2PPh3]2+[Ag(CN)2]\(_{2}^{ - }\) and [Ph3PR]+[Ag(CN)2]– (R = Et, CH=CMe2): Synthesis and Structure

Abstract

The ionic Ag(I) complexes [Ph₃PCH₂СH=CHCH₂PPh₃]²⁺[Ag(CN)2]\(_{2}^{ - }\) (I) and [Ph₃PR]⁺[Ag(CN)₂]^–, where R = Et (II), CHCMe₂ (III), have been synthesized by the reaction between potassium dicyanoargentate and alkyltriphenylphosphonium chlorides in an aqueous solution. The IR spectra of complexes I–III have the absorption bands of CN groups at 2131–2137 cm^–1. In X-ray diffraction studies, alkyltriphenylphosphonium cations were found to have a distorted tetrahedral configuration: the CPC angles are 105.6(3)°–112.8(3)° (I), 108.0(3)°–110.6(4)° (II), and 106.77(11)°–113.74(11)° (III), and the P–С bonds are 1.790(6)–1.810(6) (I), 1.774(8)–1.806(7) (II), and 1.745(3)–1.806(2) Å (III). In the [Ag(CN)₂]^– anions, the СAgC angles are 168.4(3)° (I), 175.5(3)° (II), and 180.000(2)° (III), and the Ag–C distances are 2.039(10)–2.093(10) Å. The formation of crystals for complexes I–III is generally caused by the weak hydrogen bonds N⋅⋅⋅Н–С (2.37–2.74 Å) between the hydrogen atoms of cations and the nitrogen atoms of anions.