908588-60-3Relevant academic research and scientific papers
Ruthenium tris(pyrazolyl)borate diazo complexes: Preparation of aryldiazenido, aryldiazene, and hydrazine derivatives
Albertin, Gabriele,Antoniutti, Stefano,Bortoluzzi, Marco,Castro-Fojo, Jesus,Garcia-Fontán, Soledad
, p. 4511 - 4522 (2008/10/09)
Tris(pyrazolyl)borate aryldiazenido complexes [RuTpLL′(ArN 2)](BF4)2 (1-3) [Ar = C6H 5, 4-CH3C6H4; Tp = hydridotris(pyrazolyl)borate; L = P(OEt)3 or PPh(OEt)2, L′ = PPh3; L = L′ = P(OEt)3] were prepared by allowing dihydrogen [RuTp(η2-H2)LL′]+ derivatives to react with aryldiazonium cations. Spectroscopic characterization (IR, 15N NMR) using the 15N-labeled derivatives strongly supports the presence of a linear [Ru]-N≡N-Ar aryldiazenido group. Hydrazine complexes [RuTp(RNHNH2)LL′]BPh4 (4-6) [R = H, CH3, C6H5, 4-NO2C 6H5, 4-NO2C6H4; L = P(OEt)3 or PPh(OEt)2, L′ = PPh3i L = L′ = P(OEt)3] were also prepared by reacting the [RuTp(η2-H2)LL′]+ cation with an excess of hydrazine. The complexes were characterized spectroscopically (IR and NMR) and by X-ray crystal structure determination of the [RuTp(CH 3NHNH2){P(OEt)3}(PPh3)]BPh 4 (4d) derivative. Tris(pyrazolyl)borate aryldiazene complexes [RuTp(ArN=NH)LL′]BPh4 (7-9) (Ar = C6H5, 4-CH3C6H4) were prepared following three different methods: (i) by allowing hydride species RuHTpLL′ to react with aryldiazonium cations in CH2Cl2; (ii) by treating aryldiazenido [RuTpLL′(ArN2)](BF4)2 with LiBHEt3 in CH2Cl2; (iii) by oxidizing arylhydrazine [RuTp(ArNHNH2)LL′]BPh4 complexes with Pb(OAc)4 in CH2Cl2 at -30 °C. Methyldiazene complexes [RuTp(CH3N=NH)LL′]BPh4 were also prepared by the oxidation of the corresponding methylhydrazine [RuTp(CH 3NHNH2)LL′]BPh4 with Pb(OAc)4.
