6,8-dibromo-4-chloroquinoline-3-carbaldehyde as a synthon in the development of novel 1,6,8-triaryl-1H-pyrazolo[4,3-c]quinolines

Article abstract of DOI:10.1016/j.tet.2012.10.103

2-Amino-3,5-dibromoacetophenone undergoes Vilsmeier reaction with a phosphoryl chloride-dimethylformamide mixture to afford 6,8-dibromo-4- chloroquinoline-3-carbaldehyde. The latter was reacted with arylhydrazine hydrochlorides in ethanol in the presence