A new method for the synthesis of 4H-1,3,5-oxadiazine derivatives

A new, simple method for the synthesis of 4 -1,3,5-oxadiazine derivatives was developed based on the dehydrogenation reaction of -amidoalkylated thioureas with dicyclohexylcarbodiimide. The reaction was carried out in acetonitrile under reflux for 50–60 min. The precipitated products were easily purified by crystallization from acetonitrile or ethanol. The yields were 30–70%. The structure of the synthesized compounds was determined by IR, H NMR, C NMR, MS and X-ray crystallography.