Superheated Water as Solvent in Microwave Assisted Organic Synthesis of Compounds of Valuable Pharmaceutical Interest

According to the Green Chemistry principles, water is the first choice solvent to reduce chemical waste and environmental impact of chemical industry. Reaction in water can be improved when microwave irradiation is applied to a synthetic procedure due to the possibility to reach temperatures higher than the boiling point. This is especially true when reactions are carried out in superheated/subcritical conditions (over 100 degrees C). In this paper, several synthetic procedures that use superheated or subcritical water as solvent in sealed vials under microwave irradiation as heating system, are reviewed. Noteworthy, the targets of these synthesis are valuable compounds of pharmaceutical interest.