A Simple Synthesis of (E) 5-Arylidene 5,6-Dihydro Uracils and (E) 5-Arylidene 2-Thioxo 5,6-Dihydro Uracils

Abstract

The reaction of (E) methyl 3-aryl 2-isopropyl aminomethyl 2 propenoates with phenylisocyanate or phenyl isothiocyanate followed by a treatment with sodium hydroxide under phase transfer conditions leads to (E) 5-arylidene 5,6-dihydrouracils or (E) 5-arylidene 2-thioxo 5,6-dihydro uracils. No isomerisation of the double bond occurs during the reactions.