AXIAL LIGAND SUBSTITUTIONS IN TRANS-BIS[1,2-PHENYLENEBIS(DIMETHYLARSINE)] COMPLEXES OF RUTHENIUM(II)

The series of salts trans-[RuCl(pdma)(2)L]PF6[pdma = 1,2-phenylenebis( dimethylarsine); L = MeCN 1, pyridine (py) 2, 1-methylimidazole (mim) 3, benzonitrile 4, 4-ethylpyridine 5, dimethyl sulfoxide 6, pyrazine 7 or PPh(3) 8] were prepared by reaction of trans-[RuCl(pdma)(2)(NO)](2 +) with 1 equivalent of NaN3 in acetone at room temperature followed b y reflux with an excess of L in butan-2-one. Reaction of trans-[RuCl(p dma)(2)(NO)](2+) at room temperature in mim afforded the known complex trans-[RuCl(NO2)(pdma)(2)]. Methylation of 7 with MeI at room tempera ture gave trans-[RuCl(pdma)(2)(mpyz)][PF6](2) 9 (mpyz = N-methylpyrazi nium cation). Treatment of 3 with an excess of NaN3 in refluxing mim-w ater afforded trans-[Ru(N-3)(pdma)(2)(mim)]PF6 10 which is converted i nto trans-[Ru(pdma)(2)(mim)(2)][PF6](2) 11 by reaction with NO2BF4 in acetone at room temperature, followed by heating in mim. Single-crysta l structures of trans-[RuCl(NO2)(pdma)(2)], trans-[RuCl(pdma)(2)(NO)][ PF6](2), 2 . dmf(dmf = dimethylform amide) and 11 have been determined .