Microwave-enhanced Goldberg reaction:: a novel route to N-arylpiperazinones and N-arylpiperazinediones

An unprecedented microwave-enhanced Goldberg reaction constitutes the key strategic step in the synthesis of N-arylpiperazinones, N-arylpiperazinediones and N-aryl-3,4-dihydroquinolinones. Microwave irradiation greatly accelerates the Goldberg reaction using NMP as solvent. Alkylation at the 3-position of the formed N-aryl-2-piperazinones furnishes new N-aryl-3-alkyl-2-piperazinones, (C) 2002 Elsevier Science Ltd. All rights reserved.