Thesis (M.Sc.)--Chulalongkorn University, 2008

Screening for metal halides disclosed that copper(II) chloride could catalyze the Pechmann condensation of resorcinol with ethyl acetoacetate to afford 7-hydroxy-4methylcoumarin as a major product and 4-(2,4-dihydroxyphenyl)-7-hydroxy-4-methylchroman-2-one as a minor product. In the case of chromium(III), chromium(III) chloride hexahydrate could catalyze Pechmann condensation of resorcinol with ethyl acetoacetate to obtain 7-hydroxy-4methylcoumarin in high yield. The optimum conditions for the condensation of resorcinol with ethyl acetoacetate including amount and type of catalyst, reaction temperature, amount and type of solvent were conducted. Utilizing the developed optimum conditions for the Pechmann condensation ofresorcinol with ethyl acetoacetate, other selected chemical model: pyrogallol, 3-methoxyphenol, phloroglucinol, m-cresol, 2-naphtol, 2-methylresorcinol, orcinol and 3-aminophenol could be transformed to the corresponding coumarins in moderate to excellent yield.