Direct catalytic synthesis of β-(C3)-substituted pyrroles: a complementary addition to the Paal-Knorr reaction

The synthesis of beta-(C3)-functionalized pyrroles is a challenging task and requires a multistep protocol. An operationally simple direct catalytic synthesis of beta-substituted pyrroles has been developed. This one-pot multicomponent method combined aqueous succinaldehyde as 1,4-dicarbonyl, primary amines, and isatins to access hydroxyl-oxindole beta-tethered pyrroles. Direct synthesis of the beta-substituted free NH-pyrrole is the central intensity of this work. DFT-calculations and preliminary mechanism investigation support the possible reaction pathway.

Automated summary

The study developed a simple multicomponent method for synthesizing beta-substituted pyrroles, using aqueous succinaldehyde, primary amines, and isatins. The research delved into the direct synthesis of beta-substituted free NH-pyrrole, and DFT calculations and preliminary mechanism investigation supported a possible reaction pathway.