One-pot synthesis of stable phosphonium ylides using 2-mercaptopyrimidine derivatives

Abstract

The reaction of dialkyl acetylenedicarboxylates with 2-mercaptopyrimidine and 2-mercapto-4,6-dimethylpyrimidine in the presence of triphenylphosphine leads to stable phosphorus ylides in excellent yields. These stable ylides exist in solution as a mixture of two geometrical isomers as a result of restricted rotation around the carbon-carbon partial double bond resulting from conjugation of the ylide moiety with the adjacent carbon group.

Keywords:

• Acetylenic esters
• Stable phosphorus ylides
• Triphenylphosphine
• 2-mercaptopyrimidine
• 2-mercapto-4,6-dimethylpyrimidine
• Geometrical isomers

Acknowledgements

We gratefully acknowledge financial support from the Research Council of the University of Sistan & Balouchestan and Payame Nour University of Khoy.