Efficient synthesis of 4-hydroxybenzohquinoline-2(1H)-one and some derivatives

摘要

3-(Naphlhyl-1-amino)-3-oxopropanoic acid and N,N'-di(naphthyl-1-yl)malonamide were synthesised by the reaction of 1-naphthylamine with diethyl malonate under reflux. These two compounds were then separately cyclised to 4-hydroxybenzohquinolin-2-(1H)-one in two different reactions in polyphosphoric acid. A series of esters and ethers of the 4-hydroxy group and some 3-substituted derivatives were prepared. The structures of the compounds were confirmed by infra-red NMR spectroscopy and elemental analysis.