Current Chemistry Letters (Jan 2013)
Synthesis of new heterocyclic compounds using 2-(4,7-dichloro-3,3-dimethyl-indolin-2-ylidene)malonaldehyde
Abstract
1-(2,5-Dichlorophenyl)hydrazine was converted via Fischer synthesis with isopropylmethylketone into 4,7-dichloro-2,3,3-trimethyl-3H-indole. Exposure of the indolenine to the vilsmeier reagent produced amino methylene malondialdehyde which reacted with hydrazine, arylhydrazine, urea, cyanoacetamide and thiourea to give pyrazols, pyrimidones and thiopyrimidone, respectively.