A Facile Method for the Synthesis of Binary Tungsten Iodides

Abstract

The preparation of tungsten iodides in large quantities is a challenge because these compounds are not accessible using an easy synthesis method. A new, remarkably efficient route is based on a halide exchange reaction between WCl6 and SiI4. The reaction proceeds at moderate temperatures in a closed glass vessel. The new compounds W3I12 (W3I8 ⋅2 I2) and W3I9 (W3I8 ⋅½I2) containing the novel [W3I8] cluster are formed at 120 and 150 °C, and remain stable in air. W3I12 is an excellent starting material for the synthesis of other metal-rich tungsten iodides. At increasing temperature these trinuclear clusters undergo self-reduction until an octahedral tungsten cluster is formed in W6I12 . The synthesis, structure, and an analysis of the bonding of compounds containing this new trinuclear tungsten cluster are presented.

Alkaline Earth Cluster Compounds AE[W6I14] and the Solvate [Ca(C2H6SO)6][W6I14]

“…[14][15][16] A 2 [W 6 I 14 ] compounds with A = alkaline metal are usually obtained from solid-state reactions of mixtures of a binary iodide (e.g. W 3 I 12 [17] or W 6 I 12 [18] ) and AI in appropriate proportions at elevated temperatures. At this point of state, it is likely to assume that alkaline earth (AE) compounds with the formula AE[W 6 I 14 ] can be prepared by the same way of synthesis, as testified in this report.…”

Ligand Influence on the Photophysical Properties and Electronic Structures of Tungsten Iodide Clusters

“…Practical experience has shown that the straightforward solid‐state reaction of the elements in fused silica does not proceed in an easy way and requires careful handling, and the corresponding reaction for tungsten is ineffective. [18b] This prompted us to develop new methods for the preparation of W 6 I 12 and Mo 6 I 12 for subsequent ligand‐substitution reactions. At this point, we designed new compounds containing [M 6 I 8 L 6 ] 2– clusters (M = W, Mo) with various ligands (L).…”

Cluster Helix Structure of the Binary Compound W5I12

“…Recently, a halide exchange reaction was developed by us, based on a facile reaction of WCl 6 with SiI 4 . The main product of this reaction is the tungsten iodide W 3 I 8 · 2I 2 7. This compound can be used to generate more tungsten iodide compounds that have not yet been reported in the literature.…”