Diastereoselective Synthesis of Stable Phosphorus Yields by a Three-Component Reaction between Ph3P and Acetylenic Esters in the Presence of Hydrazine Derivatives

In this work, stable crystalline phosphorus yields are obtained in good yields from the 1:1:1 addition reactions between hydrazine derivatives and dialkyl acetylenedicarboxylates in the presence of triphenylphosphine at room temperature in dichloromethane. This synthetic method has merits of high yields, mild reaction conditions, and simple experimental and work-up conditions. The obtained yields exist in solution as a mixture of two geometric isomers. This is because of the restricted rotation around the carbon-carbon partial double bond resulting from conjugation of the yields moiety with the adjacent carbonyl group.