Preparation and Stereochemistry of Cobalt(III) Complexes Containing 1,1,11,11-Tetraphenyl-4,8-diaza-1,11-diphosphaundecane or (3S,9S)-3,9-Dimethyl-1,1,11,11-tetraphenyl-4,8-diaza-1,11-diphosphaundecane, (C6H5)2PCH2CHRNHCH2CH2CH2NHCHRCH2P(C6H5)2 (R=H or CH3)

Article abstract of DOI:10.1246/bcsj.61.3503

Two new quadridentate phosphine ligands 1,1,11,11-tetraphenyl-4,8-diaza-1,11-diphosphaundecane (pp-232PNNP) and (3S,9S)-3,9-dimethyl-1,1,11,11-tetraphenyl-4,8-diaza-1,11-diphosphaundecane (SS(C)-pp-232PNNP), and several their cobalt(III) complexes were prepared and characterized.The RS(N) isomers of trans-(1+) were formed by oxidation of cobalt(II) complexes of these ligands in dichloromethane with chlorine, while the RR,SS(N), and RR(N) isomers of the pp-232PNNP and SS(C)-pp-232PNNP complexes, respectively, were derived from the corresponding carbonato complexes and hydrochloric acid.The (n+) (O-O=CO3(2-), C2O4(2-), C5H7O2(1-)) complexes yielded only a cisβ isomer.The stereochemistry of the complexes was discussed on the basis of the absorption, circular dichroism and NMR spectra.