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. The advantages of this catalytic system include simple feedstocks, green and reusable catalyst, and operational simplicity with water as the sole by-product. This finding enables an effective molecular fragment assembly strategy for synthesizing isoindolinone drug precursor skeletons.

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