Volumen XXXVIII, Fasciculus 11 (1955) -No. 4445. 393 sierte es aus Chloroform-Athanol, wobei Kristalle vom Smp. 216-224O erhalten wurden. Zur Analyse wurde 1 Std. bei loon im Hochvakuum getrocknet.

The kinetics of substitution reactions of trithionate ion, S3062-, have been studied spectrophotometrically in 50 wt % methanol-water at 20.4°and 0.137 Mionic strength. For each of the four nucleophiles examined, a rate law of the formd[Nu]/dí = A.'2[S3062~][Nu] was obtained. It was found that nucleophilic reactivity de-creases in the series thioethoxide > thiophenoxide > triphenylphosphine > cyanide. Mechanisms have been formulated which involve substitution at the bridge sulfur with consequent displacement of sulfite ion. The relative reactivities are discussed in terms of the HSAB principle. It is concluded that divalent sulfur in trithionate is a softacid center which responds principally to polarizability of the nucleophile, with basicity playing a secondary role.

Die Kinetik von Substitutionsreaktionen mit vier Nucleophilen am Trithionat‐ Ion wird spektrophotometrisch in Methanol‐Wasser untersucht.