Structural-chemical aspects of complexation in metal halide–macrocyclic polyether systems

The Autoionization of [TiF4] by Cation Complexation with [15]Crown‐5 To Give [TiF2([15]crown‐5)][Ti4F18] Containing the Tetrahedral [Ti4F18]2− Ion

“…Examples include the autoionization of alkali metals M on reaction with crown ethers to give complexed M + as well as alkalides and electrides, [2] and the autoionization of main-group and transition-metal chlorides to give cationic crown ether complexes and metal chloro anions. [3] We report herein the reaction of TiF 4 and [15]crown-5 to give [TiF 2 ([15]crown-5)][Ti 4 F 18 ]·0.5 MeCN (1). This is, as far as we are aware, the first autoionization of a metal fluoride on reaction with a crown ether, and suggests that this is a viable preparative route to other related binary fluoro metal anions.…”

Titanium(III, IV)-Containing Catalytic Systems for Production of Ultrahigh Molecular Weight Polyethylene Nascent Reactor Powders, Suitable for Solventless Processing—Impact of Oxidation States of Transition Metal

“…Thus, in entry 8, conducted under the same quantities of cocatalysts but with large amounts of THF, the system activity decreased almost threefold. This can be explained, for example, by the formation of inactive or much less active heterometallic magnesium complexes with anions [TiCl6−n·THFn] −x , similar to that previously described [23,24].…”

“…The precise composition of such complexes depends on the oxidation state of Group 4 metals and differences in acidity of electron-deficient molecules that are introduced to the system. Thus, the authors [22,23] have shown that titanium (or zirconium) in the formal +4 oxidation state in the presence of magnesium compounds is always included in the anion: [Mg(CH 3 CN) 2 [24]. The above-mentioned behavior of titanium compounds in different oxidation states, in our view, is of fundamental importance to understanding the mechanism of system I ( Figure 1) in terms of catalytically active site formation.…”

The Autoionization of [TiF4] by Cation Complexation with [15]Crown‐5 To Give [TiF2([15]crown‐5)][Ti4F18] Containing the Tetrahedral [Ti4F18]2− Ion

“…Crown ethers1 promote the autoionization of elements and compounds leading to novel anions, driven by the complexation energy of the corresponding cation. Examples include the autoionization of alkali metals M on reaction with crown ethers to give complexed M + as well as alkalides and electrides,2 and the autoionization of main‐group and transition‐metal chlorides to give cationic crown ether complexes and metal chloro anions 3. We report herein the reaction of TiF 4 and [15]crown‐5 to give [TiF 2 ([15]crown‐5)][Ti 4 F 18 ]⋅0.5 MeCN ( 1 ).…”