Reactions of [RuCl2(NO)(terpy)](+) (terpy=2,2 ' : 6 ',2 ''-terpyridine) with mono anions such as NO2-, Br- and N-3(-), and structural studies on terpyridineruthenium having a nitrosyl ligand

[RuCl2(NO)(terpy)]PF6([1]PF6) has been synthesized by the reaction of K-2[R uCl5(NO)] with terpy and characterized by single-crystal X-ray crystallogra phy. [I]PF6 has a structure in which the two chloro ligands are located tra ns to each other with the nitrosyl ligand on the plane of the terpy ligand. Reactions of [I]PF6 with mono anions such as NO2-, Br- and N-3(-) have bee n investigated. Its reactions with NO2- in H2O and CH3OH afford nitrosylter pyridine-ruthenium complexes, [Ru(OH)(NO2)(NO)(terpy)]PF6([2]PF6) and [RuCl (OCH3)(NO)(terpy)]PF6([3]PF6). respectively, whose geometrical configuratio ns differ from that of [1](+). The Br-substituted complex of [1](+), [RuBr2 -(NO)(terpy)]PF6([4]PF6), and two solvated complexes, [RUCl2(CH3CN)(terpy)] ([5]) and [RuCl(CH3CN)(2)(terpy)]PF6([6]PF6), have been formed in its reac tions with Br- and N-3(-). Structures of [2]PF6, [3]PF6 and [4]PF6 have bee n determined by singal-crystal X-ray crystallography and compared with each other.