1,4-Bis(4-nitrosophenyl)piperazine: novel bridging ligand in dinuclear complexes of rhodium(III) and iridium(III).

Wirth, Stefan; Barth, Florian and Lorenz, Ingo-Peter (2012): 1,4-Bis(4-nitrosophenyl)piperazine: novel bridging ligand in dinuclear complexes of rhodium(III) and iridium(III). In: Dalton Transactions, Vol. 41, No. 7: pp. 2176-2186

Abstract

The synthesis, spectroscopic characterization and crystal structures of the first 1,4-bis(4-nitrosophenyl)piperazine (BNPP) (4) bridged dinuclear complexes of rhodium(III) and iridium(III) are presented. The reaction of the μ2-halogenido-bridged dimers [(η5-C5Me5)IrX2]2 [X = Cl (5a), Br (5b), I (5c)] and [(η5- C5Me5)RhCl2]2 (6a) with 4 yields the dinuclear complexes [(η5-C5Me5)IrX2]2-BNPP (7a–c) and [(η5-C5Me5)RhCl2]2-BNPP (8a). All new compounds were characterized by their NMR, IR and mass spectra. The X-ray structure analyses of the obtained half-sandwich complexes revealed a slightly distorted pseudo-octahedral configuration (“three-legged pianostool”) for the metal(III) centers. The bridging BNPP ligand is σ-N coordinated by both nitroso groups and shows different conformations of the piperazine ring depending on the solvent used for crystallization. Moreover the crystal structures of 1,4-bis(4-nitrosophenyl)piperazine (4) and its precursor 1,4-diphenylpiperazine (3) are reported.

• Item Type: Journal article
• Form of publication: Publisher's Version
• Faculties: Chemistry and Pharmacy > Department of Chemistry
• Subjects: 500 Science > 540 Chemistry
• Alliance/National Licence: This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.
• Language: English