Ionic liquid/silica sulfuric acid promoted fast synthesis of a Biginelli-like scaffold reaction

Abstract

Biginelli-like scaffolds were synthesized in good yields by a three-component condensation reaction of 5,5dimethyl-1,3-cyclohexanedione, an aldehyde and urea, N-methylurea or thiourea in 1-butyl-3-methylimidazolium bromide ([bmim]Br) as ionic liquid (IL) in the presence of silica sulfuric acid (SSA) as solid acid catalyst at 100 °C within less than 2 hours. © 2007 Bentham Science Publishers Ltd.