In situ construction of two substituent-related dinuclear zinc(II) azaheterocyclic complexes from two simple Schiff base ligands with pyridyl terminal groups.

Two interesting dinuclear Zn(II)-compounds Zn 2 L 3 Cl 4 ( 1 ) and Zn 2 L 4 Cl 4 ( 2 ) were synthesized through the in situ zinc-induced reaction of simple pyridyl terminated (L 1 /L 2 )Schiff base ligands with ZnCl 2 in the mixture solvents of DMF and pyridine at 80 °C for three days (where L 1 = N-(2-pyridyl-methyl)-pyridine-2-carbaldimine, L 2 = 1-(pyridin-2-yl)-N-(pyridin-2-yl-methylene)ethanamine, L 3 = 2,3,5,6-tetra-(pyridin-2-yl)pyrazine, L 4 = 1,2-di(pyridin-2-yl)-bis(1-(pyridin-2-yl)-ethylidene)ethane-1,2-diamine). The elemental analysis (EA) and IR results reveal that in situ formation of one new ligand L 3 in 1 involves two C C coupling reactions from two molecular L 1 featuring H atom in α -carbon of C N moiety, while in situ formation of another new ligand L 4 in 2 involves one C C coupling reaction from L 2 featuring –CH 3 group in α -carbon of C N moiety. Obviously, different molecular structures between 1 and 2 closely related to the different substituents in simple Schiff base ligands. Moreover, the fluorescent properties of compounds 1 and 2 were also studied. [ABSTRACT FROM AUTHOR]