Popis: |
A series of binuclear metallosupramolecular helices [Ni2L3]4+ has been synthesized from Ni(II) salts and bis(bidentate) pyridyltriazole or aminomethyltriazole ligands, separated by ortho- (o-xpt and o-xamt, respectively), meta- (m-xpt, m-xamt), and para-xylylene (p-xpt, p-xamt) spacers. All complexes were characterized by elemental analysis, ESI-MS, and in four cases, the structures confirmed by X-ray crystallography. The xpt and xamt ligands, derived by “click” reactions, exhibit similar bonding behavior regardless of modifications in their coordination pockets and spacer groups, forming triple-helical binuclear complexes with pseudo-octahedral geometry at Ni. The crystallographically characterized complexes show shorter Ni···Ni separations with the ortho spacer ([Ni2(o-xpt)3]4+, 9.332(2); [Ni2(o-xamt)3]4+, 8.9718(10) A) than with the para spacer ([Ni2(p-xpt)3]4+, 11.574(2); [Ni2(p-xamt)3]4+, 11.899(2), 11.924(2) A). |