Cyano-bridged extended heteronuclear supramolecular architectures with hexacyanoferrates(II) as building blocks

Two cyano-bridged heteronuclear coordination polymers [{Cu(bipn)}(3)Fe(CN)( 6)](n)(ClO4)(2n). 4nH(2)O (bipn = bis(3-aminopropyl)amine) (1) and [{Cd(tet )}(2)Fe(CN)(6)](n). 3nH(2)O (tet = triethylenetetramine) (2) were synthesiz ed and their structures determined. Both complexes were obtained from the a ssembly reactions of [MLn](2+) (M = Cu, Cd; n = 1, 2) and [Fe(CN)(6)](4-) i n aqueous solutions. Complex 1 exhibits a honeycomb structure with twisty r ings formed by Cu(II), Fe(II), and cyanides. The anions ClO4- weakly coordi nate to Cu(II) and form hydrogen bonds with amino groups of bipn, while wat er molecules link to the 2D network via hydrogen bonds. In complex 2, the n eutral polymer [{Cd(tet)}(2)Fe(CN)(6)](n) forms zigzag chains. The water mo lecules insert between chains and pull them together to form a layered stru cture via a series of interchain hydrogen bonds. Thermal analyses over the temperature range 30-700 degrees C show both complexes decompose completely above 460 degrees C. (C) 2000 Elsevier Science S.A. All rights reserved.