Aplicação de diferentes fontes de energia para a síntese de 1,2,3-triazóis funcionalizados

Abstract

This work describes the synthesis of 1,2,3-triazoles using alternative energy sources in order to obtain products in high yields and in a short reaction time. Firstly, arylselanyl-phenyl-1H-1,2,3-triazoles 3a-p were synthesized via 1,3-dipolar cycloaddition from arylselanyl phenylazide 1a-g and terminal alkynes 2a-m in the presence of copper acetate monohydrate and sodium ascorbate, using a mixture of THF and H2O as solvent and microwave irradiation as energy source. The products were obtained in a short reaction time (30 minutes) and excellent yields ranging from 85 to 97%. In a second study, it was synthesized 1,2,3-triazoyl carboxamides 6a-r via organocatalyzed 1,3-dipolar cycloadditions between β-oxo-amides 4a-j and aryl azides 5a-h, in the presence of catalytic amounts of diethylamine (5 mol%), using DMSO as solvent under ultrasound irradiation at room temperature for 15 min provided the corresponding products in yields ranging from 72 to 95%. These described methods using microwave and ultrasound irradiation as alternative energy sources provided an efficient access for the synthesis of a series of 1,2,3-triazoles in good yields and in short reaction times.