LAUSR

We have developed green, efficient and powerful protocols for the preparation of 2,4,6-triarylpyridines and 1,8-dioxodecahydroacridines in the presence of Fe3O4@TiO2@O2PO2(CH2)2NHSO3H as a sulfonic acid-functionalized titana-coated magnetic nanoparticle catalyst under mild and solvent-free reaction conditions. These protocols furnished the desired products in short reaction times with good to high yields (20–40 min and 80–86% in the case of 2,4,6-triarylpyridines; 15–90 min and 80–93% in the case of 1,8-dioxodecahydroacridines). The final step of the mechanistic route in the synthesis of 2,4,6-triarylpyridines proceeds via an anomeric-based oxidation. Also, the nanomagnetic core–shell catalyst can be recycled and reused in both cases of the scrutinized one-pot multicomponent reactions with high turnover number and turnover frequency.