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Reinhard Schwesinger

Publications and source records attributed to Reinhard Schwesinger.

3 recordsLinked to original sources

Extremely base-resistant organic phosphazenium cations.

A series of peralkylated polyaminophosphazenium cations exhibiting extraordinary base resistance under phase-transfer conditions were efficiently synthesized from readily available starting materials. Their half lives under these conditions exceed those of the most stable conventional organic cations by factors of up to 3000.

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Anhydrous phosphazenium fluorides as sources for extremely reactive fluoride ions in solution.

Several peralkylated polyaminophosphazenium cations were evaluated for the generation of novel anhydrous F- salts. Two of them have been characterized by X-ray analysis and are particularly soluble, even in apolar aprotic solvents like benzene or THF, one of them even at -30 degrees C. Such solutions probably represent the most basic metal-free and stable media known to date. Comparison of these fluorides with known F- sources demonstrates that they are of unprecedented reactivity and selectivity in E2 elimination reactions.

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Acid-Base Equilibria in Nonpolar Media. 1. A Spectrophotometric Method for Acidity Measurements in Heptane.

A UV-vis spectrophotometric method for measurements of relative acidities in heptane has been developed. The phosphazene base t-BuP(4) is used as the deprotonating agent. Its protonated form is a good counterion for the anions of the acids because it is bulky, has delocalized charge, and therefore does not have specific interactions with the anions. A self-consistent scale of relative acidities in heptane spanning for 3 pK(a) units has been constructed.

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