An eco-friendly procedure for the synthesis of new phosphates using KF/Al2O3 under solventless conditions and their antifungal properties

Abstract

A versatile and environmentally friendly method for the synthesis of various organophosphorus compounds have been developed under microware conditions. We have synthesized a series of the trifluoromethyl phosphonates via Phospha-Brook rearrangement between dialkylphosphite and 3-(trifluoroacetyl)coumarins using KF/Al2O3 as a highly efficient solid catalyst under solventless conditions. Catalyst reuse, ease of separation of the pure product, and high yields are some of the unique features of this process. In addition, the mycelial growth rate method was used to examine the in vitro antifungal activities of the phosphates 4a-o against Phytophthora capsici, Fusarium oxysporum vasinfectum, Bipolaris maydis and Alternaria solani at 500 µg/mL. The results showed that compound 4n exhibited significant anti-Phytophthora capsici activity with inhibitory index of 86%.

Keywords

• Green synthesis
• Trifluoromethyl phosphonates
• Without solvent
• Phospha-Brook rearrangement