Nano-Fe3O4@ZrO2-SO3H as Highly Efficient Recyclable Catalyst for the Green Synthesis of Fluoroquinolones

Nano-Fe3O4@ZrO2-SO3H (n-FZSA), was utilized as a magnetic catalyst for the synthesis of various fluoroquinolone compounds. These compounds were prepared by the direct amination of 7- halo-6-fluoroquinolone-3-carboxylic acids with piperazine derivatives and (4aR,7aR)-octahydro-1Hpyrrolo[ 3,4-b] pyridine in water. The results showed that n-FZSA exhibited high catalytic activity towards the synthesis of fluoroquinolone derivatives, giving the desired products in high yields. Furthermore, the catalyst was recyclable and could be used at least seven times without any discernible loss in its catalytic activity. Overall, this new catalytic method for the synthesis of fluoroquinolone derivatives provides rapid access to the desired compounds in refluxing water following a simple work-up procedure, and avoids the use of organic solvents.