Novel clay-catalysed cyclisation of salicylaldehyde semicarbazones to 2H-benz[e]-1,3-oxazin-2-ones under microwave irradiation
A microwave-expediated, high yielding, synthesis of 2H-benz[e]-1,3-oxazin-2-ones (2a-j) involving cyclodehydrazination of salicylaldehyde semicarbazones (1a-j) on montmorillonite K 10 clay in solvent-free conditions is reported.