Preparation of Arylpropynamides and Their Reaction with Malonyl Acid Derivatives

Synthesis of arylpropynamides and their reactions with different malonic acid derivatives is described. Treatment of arylpropynamides with unsubstituted malonyl chloride furnished N -(3-arylprop-2-ynoyl)-6-chloro-4-hydroxy-2-oxo-2 H -pyran-3-carboxamides; monosubstituted malonyl chlorides or their derivatives, (chlorocarbonyl)ethylketenes, reacted with arylpropynamides to give 4-hydroxy-2-(phenylethynyl)-6 H -1,3-oxazin-6-ones; and the reaction of arylpropynamides with disubstituted malonyl chlorides furnished open-chain arylpropenamides exclusively.