Preparation and Characterization of Cobalt(III) Complexes Containing 4,7-Diphenyl-4,7-diphosphadecane-1,10-diamine and 4,8-Diphenyl-4,8-diphosphaundecane-1,11-diamine, NH2(CH2)3P(C6H5)(CH2)nP(C6H5)(CH2)3NH2 (n=2,3)

Article abstract of DOI:10.1246/bcsj.64.2372

Twelve new cobalt(III) complexes of the types, cisα-^p+ (L=2,4-pentanedionate (acac) and oxalate (ox) ions) (four complexes) and cisβ-^p+ (eight complexes) were prepared and characterized by ¹H NMR and absorption spectra, where rac(P)- and meso(P)-323NPPN denote rac(P)- and meso(P)-NH2(CH2)mP(C6H5)(CH2)nP(C6H5)(CH2)mNH2 with m=3 and n=2, and 333NPPN the ligand with m=3 and n=3.Reactivities of the complexes towards hydrochloric acid were examined and compared with those of the corresponding 222NPPN (m=2, n=2) and 232NPPN (m=2, n=3) complexes.All the cisα isomers yield the cisα-dichloro complexes, the 333NPPN and 222NPPN complexes being more reactive than the 232NPPN and 323NPPN complexes in which five- and six-membered chelate rings of NPPN are involved.For the cisβ isomers, the acac complexes afford +)>²⁺ except the rac(P)- and meso(P)-333NPPN complexes which give the trans-dichloro complexes, while all the ox complexes liberate the ox ion to yield the dichloro complex of the cisα, cisβ, or trans configuration.For both cisβ-acac and -ox isomers, the 222NPPN and 232NPPN complexes are more reactive than those of 323NPPN and 333NPPN, and the meso(P)-complexes are more reactive than the rac(P)-complexes.