MICROWAVE AND ULTRASOUND ASSISTED SYNTHESIS AS ECOLOGICALLY FRIENDLY METHODS IN NITROGEN HETEROCYCLIC CHEMISTRY

On the last few years, microwave and ultrasound irradiation has become a successful tool in modern medicinal and organic chemistry especially (but not only) because in many cases synthesis became ecologically friendly. As part of our ongoing efforts in the field of nitrogen heterocyclic derivatives, we present herein some core results obtained by our group in the field of N-alkylation and 3+2 cycloadditions reactions applied in the nitrogen heterocycles series, by using microwave and ultrasound irradiation. Comparative with conventional thermal heating, undeniable advantages of using microwave and ultrasound irradiation was observed in terms of higher yields, better selectivity, milder reaction conditions, decreasing of the amount of used solvent comparative with thermal heating, a dramatically decrease of the reaction time from days to minutes, decreasing of the consumed energy, etc. As a result, these reactions under microwave and ultrasound irradiation could be considered environmentally friendly.