The synthesis, Na+ binding properties of new coumarin-crown ethers

Abstract

o-Dihydroxy-3-(methylphenyl)-chromenones (coumarins; 3a-3c) were synthesized from trimethoxy-benzaldehydes through a reaction with the corresponding methylphenyl-acrylonitrile in pyridine center dot HCl and then H3O+. Dihydroxycoumarins reacted with the ditosylate or dichloride derivatives of tri-or tetraethyleneglycols in the presence of CH3CN/Na2CO3 and macrocyclic ethers with a coumarin moiety were obtained. The chromatographically purified new coumarin-crown ethers (5a-5f) were identified by IR, H-1 NMR, and Mass spectrometry. The binding constants of Na+ with the coumarin-crown ethers were determined in an 80 % dioxane/water binary solvent system at 25 degrees C from conductance measurements.