Popis: |
Treatment of ‘RuCl 3 · 3H 2 O’ with Ph 2 AsCH 2 AsPh 2 (dpam) in hot EtOH gives either trans -[RuCl 2 (dpam-As,As′)(dpam-As) 2 ] ( 1 ), or cis -[RuCl 2 (dpam-As,As′) 2 ] ( 2 ), depending on the mole ratio. On exposure to light, solutions of 2 isomerise to trans -[RuCl 2 (dpam-As,As′) 2 ] ( 3 ). Treatment of [RuCl 2 (PPh 3 ) 3 ] with two equivalents of dpam in CH 2 Cl 2 gave a mixture of two products, from which trans -[RuCl 2 (PPh 3 ) (dpam-As,As′)(dpam-As)] ( 4 ) was isolated by recrystallisation. The crystal structures of 1–4 are reported. Complexes 1 – 3 in CH 2 Cl 2 undergo electrochemical oxidation to Ru(III), and the Ru(III) form of 2 undergoes isomerisation on the voltammetric timescale to the Ru(III) form of 3 . |