A Meso Butterfly-Like\nCe(III)-Containing Antimonotungstate\nwith Catalytic Activity for Synthesizing Isoindolinones

A unique meso Ce(III)-containing antimonotungstate, {Na(OAc)(H<sub>2</sub>O)<sub>2</sub>[Ce<sub>4</sub>(tar)(Htar)<sub>2</sub>(Sb<sub>2</sub>W<sub>21</sub>O<sub>72</sub>)<sub>2</sub>(H<sub>2</sub>O)<sub>7</sub>]}<sub>2</sub><sup>44–</sup> (<b>Ce</b><sub><b>4</b></sub><b>tar</b><sub><b>3</b></sub>; H<sub>4</sub>tar = tartaric acid), consisting of two enantiomeric parts with a\nbutterfly-like configuration, was successfully synthesized by a one-pot\nin situ method and characterized. The coordination of d-\nor l-tar ligands induced the formation of Dawson-like {Ce<sub>2</sub>Sb<sub>2</sub>W<sub>21</sub>} with right or left configurations,\nthereby determining the d/l configurations of {Na(OAc)(H<sub>2</sub>O)<sub>2</sub>[Ce<sub>4</sub>(tar)(Htar)<sub>2</sub>(Sb<sub>2</sub>W<sub>21</sub>O<sub>72</sub>)<sub>2</sub>(H<sub>2</sub>O)<sub>7</sub>]}<sup>22–</sup>. Carboxyl groups link these two enantiomeric\nparts with Ce(III) ions from each other around the symmetric center\nof the <i>P</i>1̅ space group. The three types of\ntar ligands exhibit distinct coordination modes, and all coordinate\nwith at least one W(VI) atom using one carboxylate oxygen atom and\none α-OH. <b>Ce</b><sub><b>4</b></sub><b>tar</b><sub><b>3</b></sub> represents the largest case among those <i>meso</i>-dl-tar-functionalized polyoxometalates. Furthermore, <b>Ce</b><sub><b>4</b></sub><b>tar</b><sub><b>3</b></sub> exhibits excellent catalytic activity for synthesizing isoindolinones\nvia the three-component reaction of 2-acetylbenzoic acids, amines,\nand phosphine oxides.