Abstract: An environmentally benign protocol for the one-pot,
three-component synthesis of Triazolo[1,2-a]indazole-1,3,8-trione
derivatives by condensation of dimedone, urazole and aromatic
aldehydes catalyzed by HClO4/SiO2 NPS as an ecofriendly catalyst
with high catalytic activity and reusability at 100ºC under solventfree
conditions is reported. The reaction proceeds to completion
within 20-30 min in 77-86% yield.
Abstract: An efficient and green protocol for the synthesis of α-
aminonitriles derivatives by one-pot reaction of different aldehydes
with amines and trimethylsilyl cyanides has been developed using
natural alumina, alumina sulfuric acid (ASA), nano-γ-alumina, nanoalumina
sulfuric acid (nano-ASA) under microwave irradiation and
solvent-free conditions. The advantages of methods are short reaction
times, high yields, milder conditions and easy work up. The catalysts
can be recovered for the subsequent reactions and reused without any
appreciable loss of efficiency.