The Heteroleptic Cluster Cation [(W₆I₈)I₃(CH₃CN)₃]⁺

Abstract

The iodide‐rich compound [(W6I8)I3(CH3CN)3]I9 was synthesized solvothermally from W6I22 and I2 in acetonitrile. The refined crystal structure reveals the presence of the novel heteroleptic cluster cation [(W6I8)I3(CH3CN)3]+ containing the [W6I8]4+ cluster with an octahedral tungsten cluster core, coordinated by three apical iodido and three acetonitrile ligands via cluster vertices. The iodide‐rich starting material W6I22 with the addition of I2, produces the heptaiodide ion (I7)– that is present in the structure of [(W6I8)I3(CH3CN)3](I7)·I2. The novelty of this compound is based on the cationic nature of the [(W6I8)I3(CH3CN)3]+ cluster after anionic [(W6I8)I6]2– clusters and their ligand (L) substituted derivatives [(W6I8)L6]2– have been widely reported for their versatile photophysical properties.

The Remarkably Robust, Photoactive Tungsten Iodide Cluster [W6I12(NCC6H5)2]

“…The synthesis of the title compound was first achieved in an approach analogous to that reported for the cationic cluster species [W 6 I 11 (CH 3 CN) 3 ]I 7 ⋅ I 2 featuring acetonitrile as a ligand, departing from W 6 I 22 [15b] . Reactions starting from the soluble cluster species W 6 I 22 under solvothermal conditions in benzonitrile, performed in a fused quartz ampoule yielded [W 6 I 12 (NCC 6 H 5 ) 2 ] ( 1 , Figure 1, left side) as black cube‐shaped crystals (Figure 1, middle).…”

“…Four iodide and two benzonitrile ligands in these positions represent a heteroleptic cluster species. The only other reported crystal structure of an heteroleptic tungsten iodide cluster is [W 6 I 11 {CH 3 CN} 3 ]I 7 ⋅ I 2 [15b] . [W 6 I 12 (NCC 6 H 5 ) 2 ] crystallizes in the monoclinic space group P 2 1 /c , with the clusters oriented in layers in the bc plane (Figure 2, left side).…”