Butane‐1‐sulfonic acid immobilized on magnetic Fe3O4@SiO2 nanoparticles: A novel and heterogeneous catalyst for the one‐pot synthesis of barbituric acid and pyrano[2,3‐d] pyrimidine derivatives in aqueous media

Abstract

Butane‐1‐sulfonic acid immobilized on magnetic Fe3O4@SiO2 nanoparticles (Fe3O4@SiO2‐Sultone) was easily prepared via direct ring opening of 1,4‐butanesultone with nanomagnetic Fe3O4@SiO2. The prepared reagent was characterized and used for the efficient promotion of the synthesis of barbituric acid and pyrano[2,3‐d] pyrimidine derivatives. All reactions were performed under mild and completely heterogeneous reaction conditions affording products in good to high yields. The catalyst is easily isolated from the reaction mixture by magnetic decantation and can be reused at least eight times without significant loss in activity.