Über die Reaktivität von [(CH₃)₂N]₆W₂ (W≡W) gegenüber CS₂/S₈ und CS₂/Se₈. Röntgenstrukturanalyse von [(CH₃)₂NCS₂]₂W(S)(S₂) / Reactivity of [(CH₃)₂N]₆W₂ (W≡W) Towards CS₂/S₈ and CS₂/Se₈. X-Ray Structure Analysis of [(CH₃)₂NCS₂]₂W(S)(S

Abstract

<jats:title>Abstract</jats:title><jats:p> In this paper we report two improved preparation methods for [(CH<jats:sub>3</jats:sub>)<jats:sub>2</jats:sub>N]<jats:sub>6</jats:sub>W<jats:sub>2</jats:sub> (W≡W) (1), one starting from WCl<jats:sub>4 </jats:sub>(yield 51%), and a second one starting from W<jats:sub>2</jats:sub>C<jats:sub>16</jats:sub>(THF)<jats:sub>4</jats:sub> (ca. 60% yield). We have studied the reactions of 1 with different nucleophiles, among them triphenylalkylidenphosphoranes (like Ph<jats:sub>3</jats:sub>P=CH<jats:sub>2</jats:sub> and Ph<jats:sub>3</jats:sub>P=CHPh·LiCl; Ph = phenyl), sulfur and CS<jats:sub>2</jats:sub> .</jats:p><jats:p>1 reacts with S<jats:sub>8</jats:sub> and CS<jats:sub>2</jats:sub> in hexane to yield the two new compounds (Me<jats:sub>2</jats:sub>NCS<jats:sub>2</jats:sub>)<jats:sub>2</jats:sub>WS(S<jats:sub>2</jats:sub>) (4) and W(CS<jats:sub>2</jats:sub>H)(Me<jats:sub>2</jats:sub>NCS<jats:sub>2</jats:sub>)<jats:sub>2</jats:sub> (5), both containing dithiocarbamato ligands formed by insertion of CS<jats:sub>2</jats:sub> into the W-N bond. The two mononuclear compounds were characterized spectroscopically, in the case of 4 an X-ray diffraction structure analysis was performed. The reaction of 1 with Se and CS<jats:sub>2</jats:sub> , leads to the compounds 4, (Me<jats:sub>2</jats:sub>NCS<jats:sub>2</jats:sub>)<jats:sub>2</jats:sub>W<jats:sub>2</jats:sub>S<jats:sub>4</jats:sub> (6) and [(Me<jats:sub>2</jats:sub>N)<jats:sub>2</jats:sub>C]CS<jats:sub>2</jats:sub> (7), which were also characterized spectroscopically. No Se-containing compounds could be isolated.</jats:p><jats:p>4 crystallizes monoclinically, C<jats:sup>5</jats:sup><jats:sub>2h</jats:sub>-P2<jats:sub>1</jats:sub>/n, with a = 648.6(3), b = 1346.7(6) and c = 1745.9(7) pm, β = 91.85(3)°, V = 1524x10<jats:sup>6</jats:sup> pm<jats:sup>3</jats:sup> , Z = 4. The structure of the seven-coordinate tungsten compound is discussed and compared to complexes with similar ligands and geometry.</jats:p>

A reversible molecular oxygen binding system: pentacyanocobaltate(3-) inside zeolite Y

“…The preparation of CsOHCo(CN)-Y from CsOHCo-Y was repeated under Ar in an attempt to increase the concentration Co(CN)5OH3" + CN" -Co(CN)63" + OH" (5) The rates of these reactions in solution are accelerated as much as 60 times by the presence of alkali-metal cations, and cesium has been shown20 to have the greatest effect. The cause of this increase is unknown, but its magnitude does not parallel the degree of hydration or the acidity of the metal ion.…”