The synthesis and characterization of novel vicinal dioxime and its cobalt(III) complexes containing 17-membered macrocyclic ionophores

A novel (E, E)-dioxime (LH(2)) containing triaza-dioxa macrocyclic ionophores has been synthesized from the reaction of 2,3-(4'-aminobenzo)-1,4-dioxa-6,16-dioxo-11-azamethyl-7,15- diazacycloheptadecane-2-ene (4) which has been prepared from 2,3-(4'nitrobenzo)-1,4-dioxa-6, 16-dioxo-11-azamethyl-7,15-diazacycloheptadecane (3) and (E, E)-dichloroglyoxime (5). The cobalt(III) complex of LH(2) has been obtained with L' = pyridine and chloride ion as axial ligands. The BF2+-capped cobalt(III) complex is achieved by reacting the hydrogen bridged cobalt(III) complex with boron trifluoride etherate. The structures of the dioxime and its complexes are proposed according to elemental analysis, H-1 and C-13 NMR, IR and mass spectral data. Copyright (C) 1996 Elsevier Science Ltd