(SNAr)-Ar-H Reaction of Pyridines with Bis(polyfluoroalkyl)phosphonates Assisted by Electron-Deficient Acetylenes

摘要

The (SNAr)-Ar-H reaction of pyridines with bis(polyfluoroalkyl)phosphonates assisted by benzoylphenylacetylene (equimolar reactants ratio, 70-75 degrees C, 3.5-7 h, catalyst- and solvent-free) has led to bis(polyfluoroalkyl)pyridinylphosphonates in yield up to 51%. In the presence of phenylcyanoacetylene, pyridine has reacted with bis(2,2,2-trifluoroethyl)phosphonate at room temperature to regio- and stereoselectively form Z-(cyanophenylethenyl)-1,4-dihydropyridin-4-ylphosphonate, the (SNAr)-Ar-H reaction kinetic product, in high yield.