A nano silver-xerogel (Ag nps@modified TEOS) as a newly developed nanocatalyst in the synthesis of benzopyranopyrimidines (with secondary and primary amines) and gem-bisamides.

Silver nanoparticles have been prepared from a chemical reduction approach and supported on modified TEOS (tetraethylorthosilicate) xerogels to be studied as a nanocatalyst in the conversions of benzopyranopyrimidines (with primary as well as secondary amines along with the mechanism by trapping the imine intermediate) and also in the synthesis of gem-bisamides. Different conditions for the performance of the nanocatalyst have been screened and tolerance with respect to variable functionalities has been observed, resulting in excellent yields; and confirmation of products synthesized has been done using studies like ¹H NMR, ¹³C NMR and mass analysis. Also, SEM-EDX and TEM of the nanocatalyst have been performed to know the internal and external morphology, size and elemental composition. UV and XRD analysis to confirm the silver nanoparticles’ and xerogel's presence, TGA to study the thermal stability and FTIR to study the modification pattern of the nanocatalyst have been undertaken and presented in this work. [ABSTRACT FROM AUTHOR]