Efficient Green Procedure For The Synthesis Of 3, 4-Dihydropyrimidinone And Aldoxime Derivatives

Green chemistry addresses the environmental impact of both chemical products and the processes by which they are produced.Green chemistry eliminates waste at source,i.e.it is primary pollution prevention rather than waste remediation(end-of-pipe solutions). Prevention is better than cure.we shall be concerned with designing a green process for its production.The straightforward synthesis of substituted aldoxime using some solid catalysts has been accomplished under solvent-free heating,grinding and ultrasound irradiation conditions, respectively.Compared to catalysts using in the known methods,these catalysts provides as easy access to various substituted aldoximes in good to excellent yields with short reaction times.Application of ultrasound shows significant rate enhancement for the synthesis of aldoxime in the presence of the solid catalysts.The synthesis of 3,4-Dihydropyrimidin-2(1H)-ones(DHPMs) is of paramount importance in organic synthesis due to their wide range of biological activities.Herein we report our results for the synthesis of DHPMs using environmental benign solid catalysts under solvent-free heating,grinding and ultrasound irradiation conditions,respectively.The low cost catalyst has exhibited remarkable reactivity,which catalyzed one-pot condensation of aryl aldehydes,urea and ketones derivatives rapidly affords substituted 3,4-dihydropyrimidin-2(1H)-ones in good to excellent yields with short reaction times and high purity.