Synthesis Two Coumarin Derivatives Using Heterogeneous Catalysist

Abstract

Two coumarin derivatives: 5,7-di Hydroxy-4-Methyl Coumarin (1) and 6-hydroxy-1-methyl-3H-benzo[f]chromen-3-one (2) have been synthesized via Pechmann condensation using Amberlyst-15 as a green catalyst. The coumarin 1 was synthesized by the condensation of phloroglucinol 3 with the ethyl acetoacetate 4, while the coumarin 2 was synthesized from the condensation of β-keto esters 4 with the 1,3-dihydroxy naphthalene 5.The conditions of reactions were as follwing:  (1:1) the molar ration of reagents, (10mol.%, 0.2 g) Amberlyst-15  at 110°C in solvent-free conditions. The yields in this conditions  were (95%) for the compounds 1 and (88%) for the compounds 2. The possibility of recycliny the heterogenus catalyst (amberlyst -15) adds an advantage to the studied reactions. The purified products were  characterized by spectral methods: FT-IR, ¹H-NMR , ¹³C-NMR.