A green and chemoselective synthesis of coumarins via Pechmann condensation using recoverable heterogeneous catalyst (Au@pSiO₂)

Nano Au@porous SiO 2 as a heterogeneous catalyst was prepared and characterized by Fourier transform infrared, X‐ray powder diffraction, transmission electron microscopy, thermogravimetric analysis and inductively coupled plasma–atomic emission spectroscopy techniques and then used as an efficient catalyst in the condensation of various phenols with ethyl acetoacetate for the preparation of coumarin derivatives through the Pechmann reaction. The...