Synthesis of α‐Aminonitriles and 5‐Substituted 1 HH ‐Tetrazoles Using an Efficient Nanocatalyst of Fe ₃3 O ₄4 @SiO ₂2 –APTES‐supported Trifluoroacetic Acid

摘要

> Fe ₃ O ₄ @SiO ₂ –APTES‐supported trifluoroacetic acid nanocatalyst was used for the one‐pot synthesis of α‐aminonitriles via a three‐component reaction of aldehydes (or ketones), amines, and sodium cyanide. This method produced a high yield of 75–96% using only a small amount of the catalyst (0.05?g) in EtOH at room temperature. The catalyst was also employed for the synthesis of 5‐substituted 1 H ‐tetrazoles from nitriles and sodium azide in EtOH at 80°C. The tetrazoles were produced with good‐to‐excellent yields in a short reaction time of 4?h. Both synthetic methods were carried out in the absence of an organic volatile solvent. Because the supported trifluoroacetic acid generated a solid acid on the surface, thus the acid corrosiveness was not a serious challenge. This heterogeneous nanocatalyst was magnetically recovered and reused several times without significant loss of catalytic activity.