We have synthesized 2-(4-chlorophenyl)-8-(methylthio)-6-imino-4-phenyl-2,6,9,9a-tetrahydropyrimido[2,1-b][1,3]oxazine-7-carbonitrile (3) by the reaction of 6-(4-chlorophenyl)-4-phenyl-6H[1,3]oxazin-2-amine (2) with 2-(bis (methylthio)methylene)malononitrile in the presence of catalytic amount of potassium carbonate in DMF under reflux condition. The aminooxazine was prepared by the reaction of chalcone (1) with urea in the presence of ethanol and sodium hydroxide under reflux condition. The synthesized compounds were characterized by spectral methods. The compound (3) possesses replaceable methylthio (-SCH3) group at 8 position. The compound (3) react with various nucleophiles like substituted aromatic amines, aromatic phenols, hetarylamines and active methylene compounds to give 2-(4-chlorophenyl)-8-(substituted)-6-imino-4-phenyl-2,6,9,9a-tetrahydropyrimido[2,1-b][1,3]oxazine-7-carbonitriles in good yields.
Key words: Claisen-Schmidt condensation, Michael addition reaction, 2-(bis (methylthio) methylene)malononitrle, urea.
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