A Novel Three Component Reaction: The Synthesis of Stable, Highly Functionalized 1,4-Diionic Nitrogen Betaines

Abstract

The protonation of a highly reactive 1,4-dipole generated in the reaction between pyridine or isoquinoline and dialkyl acetylenedicarboxylates by the acidic C-H group of (ethoxycarbonylmethyl) triphenylphosphonium bromide leads to a vinyl pyridinium cation derivatives, which undergo a carbon-centered Michael type addition with the conjugate base of the CH-acid to produce highly functionalized stable 1,4-diionic nitrogen betaines.

Keywords:

• 1,4-diionic nitrogen betaines
• dialkyl acetylenedicarboxylates
• isoquinoline
• pyridine

Acknowledgments

We gratefully acknowledge the financial support from the Research Council of Shahid Beheshti University, Tehran, Iran.