Clean and efficient synthesis of flavanone in sub-critical water

Subcritical water (SbcW) is one of the environmentally benign medium for organic chemical reactions, especially for acid/base catalyzed reactions without using acid or base. However, problems such as low reaction rates and poor selectivity that greatly hinder the application of this attractive technique in industrially interesting processes. Synthesis of flavanones was studied in water at subcritical temperature (250 °C). SbcW was found to be a very promising solvent. The highest flavone product yield in subcritical water was 64% in 60 min at 250 °C. Any side reactions or by-products were did not observed under these conditions.