Preparation and Characterization of Cobalt(III) Complexes Containing 3,7-Diphenyl-3,7-diphosphanonane-1,9-diamine, NH2CH2CH2P(C6H5)CH2CH2CH2P(C6H5)CH2CH2NH2

Article abstract of DOI:10.1246/bcsj.63.2051

New cobalt(III) complexes with the titled ligand and its analog, cisα-n+ (L=2,4-pentanedionate (acac) and oxalate (ox) ions, and ethylenediamine (en)), cisβ-n+ (L=acac and ox) and cisα-2+ and cisβ-2+ were prepared and characterized by 1H- and 13C-NMR, and absorption spectra, where rac(P)- and meso(P)-232NPPN and -222NPPN denote racemic(P)- and meso(P)-NH2CH2CH2P(C6H5)(CH2)nP(C6H5)CH2CH2NH2 with n=3 and 2, respectively.All the cisα isomers except the en complex react with concd hydrochloric acid at room temperature to yield the corresponding cisα-dichloro complexes.For the cisβ isomers, the acac complexes dissociate one amino group of NPPN reversibly depending on the acidity of solution, yielding 3+, while the ox complexes of rac(P)- and meso(P)-232NPPN yield the cisα and trans-dichloro complexes, respectively in hydrochloric acid.All the cisβ isomers except + decompose slowly in concd hydrochloric acid to give Co(II) species.