
TY  - JOUR
A1  - Curtis, NF 
A1  - Siriwardena, A 
T1  - Compounds of Cobalt(III) With <I>trans</I>-6,13-Diamino-6,13-dimethyl-1,4,8,11-tetraazacyclotetradecane
JF  - Australian Journal of Chemistry
JO  - Aust. J. Chem.
Y1  - 1991
VL  - 44
IS  - 8
SP  - 1023
EP  - 1040
KW  - 
UR  - https://doi.org/10.1071/CH9911023 
N2  - Compounds are described of cobalt(III) with the macrocycle trans-6,13-diamino-6,13-dimethyl-1,4,8,11-tetraazacyclotetradecane ( diam ) of the types [Co(diam-N6)]3+, with diam in octahedral coordination, with the primary amino substituents coordinated trans; [Co(diam-N5)X]2,3+ and [Co(diamH-N5)X]3,4+, with diam in square pyramidal pentacoordination , with a ligand X,X-coordinated trans to the primary amino substituent and with the non-coordinated amino substituent neutral or monoprotonated, respectively; and trans-[Co(diamH-N4)X2]2+ and trans-[Co(diamH2-N4)X2]3+, with diam in planar tetracoordination, with trans ligands X-, and with one or both amino groups protonated , respectively. The diam and [Co(H2O)6](ClO4)2 in water exposed to the air react to sequentially form [Co( diam )]2+, trans-[{Co(diam-N5)}2(O2)]4+, trans-[Co(diam-N5)(OH)]2+ and [Co(diam-N6)]3+ cations. The &#956;- peroxo or hydroxo compounds can be used to prepare other N5-cations including [Co(diamH-N5)(H2O)]4+, [Co(diamH-N5) Cl ]3+ and [Co(diam-N5) Cl ]2+. [Co(diamH2-N4)]4+ formed by reduction of [Co(diam-N6]3+ with zinc amalgam in hydrochloric acid reoxidizes in air to form trans-[Co(diamH2-N4)Cl2]3+ and a [Co(diamH-N5) Cl ]2+ cation isomeric with that obtained from the hydroxo compound. The N4-tetra- and N5-penta-coordinated forms are stable in acid solution, but in base convert sequentially into the N6-hexacoordinated form in equilibrium with trans-[Co(diam-N5)(OH)]2+. Preparations, spectroscopic properties, and interconversion reactions of compounds of these cations, and some bromo, thiocyanato and acetato analogues are reported. 
ER  -

