Interesting Synthetic Approaches Towards [1]Benzopyrano[4,3-b]quinolines via Intramolecular Reaction of Nitrilium Salts
Abstract
The o-allyloxybenzanilides 2a,b,d and o-propargyloxybenzanilides 3a–f are prepared and converted to the corresponding dihydro[1]benzopyrano[4,3-b]quinolinium hexachloroantimonate 6a and [1]benzopyrano[4,3-b]quinolines 9a–e, 10 upon treatment with PCl5 followed by SbCl5.