A crystalline Sm(III)-containing antimonotungstate with efficient catalytic activity in three-component reaction for isoindolinones synthesis

The development of the three-component catalytic system for constructing isoindolinones from simple feedstocks is both significant and challenging. In this study, a unique tartrate-linked dimeric samarium-antimonotungstate [Sm2(H2O)6(tar)(Sb2W21O72)]220- (Sm4tar2, H4tar = tartaric acid) was synthesized via a one-step method at room temperature using an acetate buffer solution. The dimeric polyanion of Sm4tar2 shows a centrosymmetric structure with a parallelogram-like arrangement and comprises two enantiomeric {Sm2(H2O)6(Sb2W21O72)} moieties connected by two enantiomeric tar ligands. Sm4tar2 demonstrates efficient catalytic activity in the three-component reaction involving 2-acylbenzoic acids, primary amines, and phosphine oxides to form 3,3-disubstituted isoindolinones. This finding enables an effective molecular fragment assembly strategy for synthesizing isoindolinone drug precursor skeletons.