CoII and CuII Fluorescent Complexes with Acridine-Based Ligands

The condensation reaction of salicylaldehyde or 2-hydroxynaphthaldehyde with a diamino organic group (Acridine Yellow or diaminoacridine) resulted in the Schiff-base ligands ACRI-1, ACRI-2 and ACRI-3, with the last two hitherto unknown. Fluorescent ACRI-1, ACRI-2 and ACRI-3 were designed to provide iminophenolic binding pockets for two transition metals and ferromagnetic exchange between the metals. Following our report on the complex [Co2(ACRI-1)2] (1Co), we report herein the reactions of ACRI-1, ACRI-2 and ACRI-3 with CoII and CuII salts, which afforded the new fluorescent complexes [Cu2(ACRI-1)2] (1Cu), [Co2(ACRI-2)2] (2Co), [Cu2(ACRI-2)2] (2Cu), [Co2(ACRI-3)2(H2O)4] (3Co) and [Cu2(ACRI-3)2] (3Cu).