Self-assembly of N,N′,N″,N‴-tetra(pyridin-4-yl)-1,4,7,10- tetraazacyclododecane-1,4,7,10-tetracarboxamide with Zn2+ or Cd2+ ions
Journal
European Journal of Inorganic Chemistry
Journal Issue
8
Pages
1698-1703
Date Issued
2006
Author(s)
Abstract
Abstract We report the design and synthesis of N , N′ , N″ , N″′ ‐tetra(pyridin‐4‐yl)‐1,4,7,10‐tetraazacyclododecane‐1,4,7,10‐tetracarboxamide ( L ), which contains four N ‐(pyridin‐4‐yl)carboxamide groups as functional appendages, as well as the structural and luminescence properties of its Zn 2+ and Cd 2+ complexes. The reaction of ZnBr 2 with L forms the two‐dimensional coordination polymer [ZnBr 2 ( L ) 1/2 ] n ( 1 ). In the two‐dimensional domain, the 68‐membered metallomacrocycles as well as 12‐membered 1,4,7,10‐tetraazacyclododecane (cyclen) units propagate into two‐dimensional extended structures. Interestingly, the metallomacrocycles are stacked to form one‐dimensional parallelogram channels in the solid state. In addition, the reaction of CdX 2 (X = Br, I) with L forms the isomorphous, three‐dimensional coordination networks [CdX 2 ( L )] n [X = Br ( 2 ), I ( 3 )], which have tubular channels in the solid state. L in 1 – 3 is tetradentate and acts as a versatile connector in the construction of supramolecular coordination networks. The 34‐membered metallomacrocycles and 12‐membered cyclen macrocycles of 2 and 3 also propagate into three‐dimensional extended structures. Unlike those of 1 and 2 , the emission maximum at around 439 nm in the iodo compound 3 can be assigned to a ligand‐to‐metal charge‐transfer (LMCT) transition as the excited state upon photoexcitation. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Type
journal article