An Efficient Synthesis of 4,5-Dihydro-3(2H)-pyridazinone Derivatives

Abstract

Reaction of hydrazine with 5-(2-aryl-2-oxo-ethan-1-yl)-5-R Meldrum's acids 3 gives 4,6-disubstituted 4,5-dihydropyridazin-3(2H)-ones 4 at room temperature. The method is simple and the yield is good. The production of the starting material 3 also is discussed.