In this research, nano-SiO2–H3BO3 is introduced as a novel environmentally benign and recyclable heterogeneous catalyst for the synthesis of aminonaphthols under solvent-free conditions without an additional co-catalyst or additive in air. This synthesis method offers several advantages, such as a green and eco-friendly protocol, operational simplicity, mild reaction conditions, short reaction times, higher yields and easy work-up procedures. The work-up of these very clean reactions involves only recrystallization of the product from ethanol and recovery of the catalyst by filtration. The catalyst can be reused several times without losing activity.
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