Abstract
A distinct approach for the synthesis of 1,3,3-trisubstituted 4,5-dioxopyrrolidines and 1,3,4,5-tetrasubstituted 1,2,3,6-tetrahydropyrimidines has been discovered, in the form of a three-component reaction of nitroarenes, formaldehyde, and dialkyl acetylenedicarboxylates using indium in dilute aqueous HCl at room temperature. The molar ratios of these substrates are 1:1:4 and 2:1:4 for the preparation of dioxopyrrolidines and tetrahydropyrimidines, respectively. The reactions involve the reduction of nitro compounds to amines, which are simultaneously attacked by dialkyl acetylenedicarboxylates and formaldehyde. The products are formed in good to high yields.