First Pentanuclear Molybdenum Iodide Cluster (Bu4N)[Mo5OI13]: Synthesis and Structure

Abstract

The first iodide cluster of molybdenum with the metal cage in the form of a tetragonal pyramid (Bu4N)[Mo5OI13]·THF (I) and cocrystallizate (Bu4N){[Mo5OI13]0.9[Mo6I14]·THF (II) are synthesized for the first time by heating a LiI–I2–Mo mixture in a temperature range of 300–400°С followed by the extraction of the product. Complexes I and II are studied by X-ray diffraction analysis (CIF files CCDC nos. 2063029 (I) and 2063030 (II)). The molybdenum atoms in [Mo5OI13]– form a square pyramid with Mo–Mo distances of 2.67 Å between the basal molybdenum atoms and the Mo–Mo distances equal to 2.72 Å between the apical and basal molybdenum atoms. The oxygen atom is coordinated to the pyramid base (Mo–μ4-O 2.10 Å). The cluster anion [Mo5OI13]– can be presented as the octahedral cluster anion [Mo6I14]2– in which the position of the {MoI}– fragment (d0, 6e) is occupied by the isoelectronic oxygen atom (s2p4, 6e). In the structure of compound II, the [Mo5OI13]– and [Mo6I14]2– cluster anions occupy close atomic positions.

Improved Synthesis of (TBA)2[W6Br14] Paving the Way to Further Study of Bromide Cluster Complexes

“…The anion 5a can be visually represented as anion 5c , in which one vertex of the W–Br a octahedron has been removed. A similar example of cocrystallization for five-nuclear molybdenum cluster complexes (TBA)­[Mo 5 I 13 ]/(TBA)­[Mo 5 I 13 O] is known in the literature . The bond lengths W–W [2.6075(4)–2.6482(4) Å] and W–Br [2.5318(8)–2.6222(8) Å] are in good agreement with the corresponding lengths for the known compound W 5 Br 12 ·SbBr 3 : W–W [2.6081(9)–2.674(1) Å] and W–Br [2.509(1)–2.692(1) Å] .…”

“…A similar example of cocrystallization for five-nuclear molybdenum cluster complexes (TBA)[Mo 5 I 13 ]/(TBA)[Mo 5 I 13 O] is known in the literature. 72 The bond lengths W−W [2.6075(4)−2.6482( 4) Å] and W−Br Photodecomposition of the Nitrate Cluster Complex. Photostability is one of the advantages of most octahedral cluster complexes.…”