New route to N‐aryl and N‐heteroaryl derivatives of 4‐hydroxy‐3‐quinolinecarboxamides

The synthesis of N‐aryl and N‐heteroaryl substituted 4‐hydroxy‐3‐quinolinecarboxamides 1 is described. The attack of dianions 12 of N‐aryl substituted acetamides on the C‐4 carbonyl of 4H‐3,1‐benzoxazin‐4‐ones 11 gave rise to ketoamides 13, which smoothly cyclised in the presence of bases to afford quinolinecarboxamides 1. By this method, a large number of 2‐substituted 4‐hydroxyquinolinecarboxamides can be prepared.