Reactivity with aryldiazonium cations of hydrazine complexes of ruthenium and osmium

The bis(amine) derivative [Os(NH3)2L4](BPh4)2 (1) formed when bis(hydrazine) complex [Os(NH2NH2)2- L4](BPh4)2 was reacted with aryldiazonium salt [ArN2](BF4) in CH2Cl2 [L = P(OEt)3; Ar = 4-CH3C6H4]. Instead, reaction in (CH3)2CO afforded the bis(hydrazone) derivative [Os{NH2N@C(CH3)2}2L4](BPh4)2 (2). The chloro-amine derivative [RuCl(NH3)L4](BPh4) (3) formed by reaction with [ArN2](BF4) in CH2Cl2 of complex [Ru(NH2NH2)2L4](BPh4)2, whereas amine-carbonyl derivative [Ru(NH3)(CO)L4](BPh4)2 (4) was obtained from [Ru(CO)(NH2NH2)L4](BPh4)2. Treatment of [Ru(NH2NH2)2L4](BPh4)2 with [ArN2](BF4) in (CH3)2CO afforded the bis(hydrazone) derivative [Ru{NH2N@C(CH3)2}2L4](BPh4)2 (5). The complexes were characterised by IR and NMR spectroscopy and by X-ray crystal structur