The organometallic double metal cyanide [(Me2Sn)3{Co(CN)6}2·6H2O]. A three-dimensional framework of infinite, stapled ribbons

The admixture of aqueous Me2SnCl2–Me3SnCl solutions to solutions of K3[Co(CN)6] in the molar ratios 3:0:2 and 1:1:1, respectively, affords precipitates of [(Me2Sn)3{Co(CN)6}2·6H2O] (1) and [(Me2Sn)(Me3Sn)Co(CN)6] (2). Another synthesis of 2 is based upon the bromination of [(Me3Sn)3Co(CN)6] in MeOH. The crystal structure analysis of 1 reveals stacks of infinite planar ribbons built up of trans-Me2Sn(μ-NC)4 and trans-Me2Sn(μ-NC)2(OH2)2 units as well as of trans-Co(CN)2 fragments with terminal CN-ligands. Sn←OH2⋯(NC)2 hydrogen bonds interlink adjacent ribbons. Multinuclear (13C, 15N, 59Co, 119Sn) CPMAS solid-state NMR studies of 1 suggest some intra-ribbon dynamics, and help in proposing both a plausible architecture for anhydrous 2 and a better understanding of the nature of another precipitate 5 resulting from the admixture of a Me2SnCl2/Me3SnCl solution to a solution of K4[Fe(CN)6] (1:2:1).