Background: Aminolysis of lactones is an important reaction for the synthesis of hydroxy
amides. This reaction generally requires rather harsh conditions, such as high pressure and temperature
or strong alkali metal catalysts. Microwave-assisted reactions have provided a great impetus to organic
synthesis, especially for accelerating the reactions. The combination of microwave heating and solventfree
conditions is a particularly attractive methodology in modern organic synthesis because it leads to
enhanced conversion rates, easier work-up, higher yields and in general cleaner reactions.
Methods: A simple, efficient and eco-friendly procedure was developed for the preparation of hydroxy
amides from a variety of amines and lactones using microwave irradiation under solvent- and catalystfree
Results: In the synthesis of hydroxy amides described herein, the reactions were conducted using microwave
irradiation at temperatures of 130 °C and reaction times of 30-60 min. We investigated reactions
of lactones with amines of different nucleophilic character and steric hindrance. Primary, secondary,
aliphatic, aromatic and cyclic amines (2 equiv.) were used in the reactions with γ-butyrolactone or
γ-valerolactone (1 equiv.). The yields of the purified products were generally very good and varied according
to the amine used in most cases. An important feature is that despite no additive/catalyst is used
the reaction times were shorter compared to all the works described so far. Neither an inert atmosphere
nor solvent and additives/catalysts are required in this microwave irradiation procedure.
Conclusion: In summary, we have demonstrated a simple and efficient method for the preparation of
hydroxy amides, employing a green methodology. Simple work-up procedure and high yields obtained
using MW irradiation, under solvent-, support and catalyst-free conditions show the superiority of this
work over the existing methods.