Complexes with other Tetramine Ligands

In contrast to the complexes with trien, complexes with 3,7-diaza-l,9-nonanediamine, NH2CH2CH2NHCH2CH2CH2NHCH2CH2NH2 (2,3,2-tet) markedly prefer the tram geometry. Aerial oxidation synthesis produced only tram complex aqueous 

The ligand 4,7-diaza-l,10-decanediamine, NH2CH2CH2CH2NHCH2CH2NHCH2-CH2CH2NH2 (3,2,3-tet) coordinates to cobalt(III) preferably with tram geometry the air oxidation synthesis gives tram (RR, SS racemate)-[CoCl2(3,2,3-tet)] CIO4. 

The stereochemistry of dianionocobalt III) complexes with methyl-sul tituted trienor with 2,3,2-tet derivatives - have been extensively elucidated by Yoshikawa and co-workers. 

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Other studies have dealt with the aquation rates of some diacido cobalt(III) tetramine complexes containing asymmetric tetramine ligands, activation parameters for the aquation of frans-[Co(pn)2Cl2] , polyelectrolyte catalysis in the aquation of [Co(ox)3] in binary mixtures... 

The tripodal compounds 6, 7, 8 and 9 are known to coordinate to lanthanides as well as anions however, it would be interesting to see if they coordinate to transition metals too. There are examples of trigonal bipyramidal cobalt complexes in which one apical and three equatorial coordination sites are provided by a tripodal tetramine ligand with the other apical position being occupied by a counterion. Indeed, when a solution of compound 9 in chloroform is shaken with... 

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