Axial ligand substitutions in trans-bis[1,2-phenylenebis(dimethylarsine)] complexes of ruthenium(II)

Abstract

The series of salts trans-[RuCl(pdma)₂L]PF₆[pdma = 1,2-phenylenebis(dimethylarsine); L = MeCN 1, pyridine (py)2, 1-methylmidazole (mim)3, benzonitrile 4, 4-ethylpyridine 5, dimethyl sulfoxide 6, pyrazine 7 or PPh₃8] were prepared by reaction of trans-[RuCl(pdma)₂(NO)]²⁺ with 1 equivalent of NaN₃ in acetone at room temperature followed by reflux with an excess of L in butan-2-one. Reaction of trans-[RuCl(pdma)₂(NO)]²⁺ at room temperature in mim afforded the known complex trans-[RuCl(NO₂)(pdma)₂]. Methylation of 7 with MeI at room temperature gave trans-[RuCl(pdma)₂(mpyz)][PF₆]₂9(mpyz =N-methylpyrazinium cation). Treatment of 3 with an excess of NaN₃ in refluxing mim–water afforded trans-[Ru(N₃)(pdma)₂-(mim)]PF₆10 which is converted into trans-[Ru(pdma)₂(mim)₂][PF₆]₂11 by reaction with NO₂BF₄ in acetone at room temperature, followed by heating in mim. Single-crystal structures of trans-[RuCl(NO₂)(pdma)₂], trans-[RuCl(pdma)₂(NO)][PF₆]₂, 2·dmf (dmf = dimethylformamide) and 11 have been determined.