Some cyclic tetra-amines and their metal-ion complexes. Part II. Complexes of cobalt(III) with two isomeric hexamethyl-1,4,8,11-tetra-azacyclotetradecanes and monodentate ligands
Abstract
Cobalt(III) derivatives of two isomeric cyclic tetra-amines (hexamethyl-1,4,8,11-tetra-azacyclotetradecane—teta and tetb), are prepared by oxidation of equimolar amounts of the amine and a cobalt(II) salt, in aqueous ethanol buffered to pH∼6. The trans derivatives [Co(teta)(H2O)2]3+, [Co(teta)XY]+, (X = Y = OH–, Cl–, Br–, NCS–, NO2–, CN–; X = NO2–, Y = OH–; X = Cl–, Y = N3–), [Co(teta)(H2O)(NO2)]2+, and [Co(tetb)X2]+(X = Cl–, CN–, N3–, NO2–) are described.