Reactivity of osmium(VI) nitrides with the azide ion

A variety of reactions occur between trans-[Os-VI(tpy)(Cl)(2)(N)](+) (1) (tpy=2,2':6',2''-terpyridine) or [Os-VI(tpm)(Cl)(2)(N)](+) (2) (tpm=tris(1-pyrazolyl)methane) and N-3(-). The reaction between 2 and N-3(-) gives the stable dinitrogen complex Os-II(tpm)(Cl)(2)(N-2), but with 1 the chemistry is solvent dependent. One-electron reduction to give trans,trans-(tpy)(Cl)(2)Os-II(N-2)Os-II(Cl)(2)(tpy) occurs in nonpolar solvents. 1 and 2 react with N-3(-) in the presence of CS2 to give the thionitrosyls [Os-II(L-3)(Cl)(2)(NS)](+) (L-3=tpy,tpm), SCN-, and N-2. A reaction between 1 and excess N-3(-) in CH3CN occurs to give the first Os-III-5-CH3-tetrazolate complex, and it has been characterized by X-ray crystallography (structure shown).