Magnetic Graphitic Carbon Nitride-Catalyzed Highly Efficient Construction of Functionalized 4 H -Pyrans

A high-yielding, practical, efficient, and environmentally benign one-pot multicomponent synthesis of functionalized 2-amino-4 H-pyrans from -dicarbonyl compounds, malononitrile, and aldehydes is presented. Good to excellent yields were obtained under mild reaction condition and with short reaction times by using magnetite-supported graphitic carbon nitride as a truly recyclable catalyst. This efficient and simple technique avoids the use of solvent extraction and column chromatography. In addition, the catalyst can be easily and effectively recovered and reused several times without significant loss of its catalytic activity.