Novel one- and two-dimensional Ag(I) networks generated from double Schiff base ligands with disubstituted quinoxaline diazenes as the terminal binding sites

The new double Schiff base ligand L7 (2,5-bis(2-benzodiazine)-3,4-diaza-2,4-hexadiene) with disubstituted quinoxaline diazenes was synthesized. Four new polymeric Ag(I) complexes based on L7, namely {Ag-3-(L7)(3)(BF4)(3)(CH2Cl2)(3)(H2O)}(n) (1), {Ag-2.5(L7)(1.5)(ClO4)(2.5)(H2O)(2)}(n) (2), {Ag-4(L7)(3)(PF6)(4)}(n) (3), and {Ag-4(L7)(3)(SbF6)(4}n) (4), have been synthesized successfully. They were fully characterized by infrared spectroscopy, elemental analysis, and single-crystal X-ray diffraction. In compound 1, two Ag(I) atoms are held together by two L7 ligands through the inside middle chelating N donors to generate a binuclear "X-shaped" helical secondary building block. In compounds 2-4, three Ag(I) atoms are held together by three L7 ligands through the inside middle chelating N donors to afford a trinuclear crownlike secondary building block. These spontaneous self-organized supramolecular secondary building blocks were further linked together into the higher extended hierarchy through outside N-Ag(I) coordination interactions. Compound 1 features a two-dimensional net containing a molecular cage, and compounds 2-4 feature two- (2 and 3) and one-dimensional (4) molecular crown-containing polymeric complexes in the solid state, respectively.