RESUMO
Using 4-(4'-pyridyl)aniline as a simple organic building block in combination with three different aldehyde components together with metal(II) salts gave three different Fe8 Pt6 -cubes and their corresponding Zn8 Pt6 analogues by employing the subcomponent self-assembly approach. Whereas the use of zinc(II) salts gave rise to diamagnetic cages, iron(II) salts yielded metallosupramolecular cages that show spin-crossover behaviour in solution. The spin-transition temperature T1/2 depends on the incorporated aldehyde component, giving a construction kit for the deliberate synthesis of spin-crossover compounds with tailored transition properties. Incorporation of 4-thiazolecarbaldehyde or N-methyl-2-imidazole-carbaldehyde yielded cages that undergo spin-crossover around room temperature whereas the cage obtained using 1H-4-imidazolecarbaldehyde shows a spin-transition at low temperatures. Three new structures were characterized by synchrotron X-ray diffraction and all structures were characterized by mass spectrometry, NMR and UV/Vis spectroscopy.
RESUMO
Tetrakis(chloromethyl)phosphonium chloride monohydrate, C(4)H(8)Cl(4)P(+) x Cl(-) x H(2)O or P(CH(2)Cl)(4)(+) x Cl(-) x H(2)O, is the first crystal structure determination of a tetrakis(halogenomethyl)phosphonium compound to date. The only comparable structures known so far are of phosphonium ions containing just one halogenomethyl group. The solvent water molecule interacts with the Cl(-) anion via hydrogen bonds, with O...Cl distances of 3.230 (2) and 3.309 (2) A. The structure also contains several C-H...Cl(-) and C-H...O contacts, though with longer D...A distances [D.A 3.286 (3)-3.662 (2) A] or bent D-H...A angles. For these reasons, the C-H...Cl(-) and C-H...O interactions should not be considered as strong hydrogen bonds.