Three-Dimensional Cadmium(II) Cyanide Coordination Polymers with Ethoxy-, Butoxy- and Hexyloxy-ethanol

Abstract

The three novel cadmium(II) cyanide coordination polymers with alkoxyethanols, [Cd(CN)2(C2H5OCH2CH2OH)]n (I), [{Cd(CN)2(C4H9OCH2CH2OH)}3{Cd(CN)2}]n (II) and [{Cd(CN)2(H2O)2}{Cd(CN)2}3·2(C6H13OCH2CH2OH)]n (III), were synthesized and charcterized by structural determination. Three complexes have three-dimensional Cd(CN)2 frameworks; I has distorted tridymite-like structure, and, II and III have zeolite-like structures. The cavities of Cd(CN)2 frameworks of the complexes are occupied by the alkoxyethanol molecules. In I and II, hydroxyl oxygen atoms of alkoxyethanol molecules coordinate to the Cd(II) ions, and the Cd(II) ions exhibit slightly distort trigonal-bipyramidal coordination geometry. In II, there is also tetrahedral Cd(II) ion which is coordinated by only the four cyanides. The hydroxyl oxygen atoms of alkoxyethanol connects etheric oxygen atoms of the neighboring alkoxyethanol by hydrogen bond in I and II. In III, hexyloxyethanol molecules do not coordinate to the Cd(II) ions, and two water molecules coordnate to the octahedral Cd(II) ions. The framework in III contains octahedral Cd(II) and tetrahedral Cd(II) in a 1:3 ratio. The Cd(CN)2 framework structures depended on the difference of alkyl chain for alkoxyethanol molecules.