Synthesis, characterization and structure of the salicylate salt of [RuH(terpy)(PPh3)2]+(terpy = 2,2′ : 6′,2″-terpyridine)

Abstract

The complex [RuH(terpy)(PPh₃)₂][C₇H₅O₃]1 has been synthesised from 2,2′ : 6′,2″-terpyridine (terpy) and [RuH(C₇H₅O₃)(PPh₃)₃] where C₇H₅O₃ is salicylate. It shows ν(RuH) at 1960 cm^–1 and a hydridic ¹H triplet at δ–6.30, J= 26.2 Hz. The crystal structure of 1 has been determined: space group Pnam, a= 14.705(7), b= 15.380(6), c= 22.667(9)Å, and Z= 4. The PPh₃ ligands are mutually trans about the Ru atom which, with the terpy ligand, lies on a mirror plane. The Ru–N distance trans to the hydride ligand is relatively long. The salicylate ion is internally hydrogen bonded. The complex displays a metal-to-ligand charge transfer transition (480 nm) and an irreversible metal oxidation Ru^II→ Ru^III at ca. 0.6 V.