Vitamin B1‐Catalyzed Multicomponent Reaction for Efficient Synthesis of an Isoxazolone Compound by Using Ultrasound in a Water and Its Selective Identification of Metal Ions

Abstract

AbstractAn efficient synthesis of 3‐methyl‐4‐(arylmethylene)isoxazol‐5(4H)‐ones are developed via cyclocondensation in 84–94 % yields starting from aromatic aldehydes, hydroxylamine with ethyl acetoacetate vitamin B1 is catalyzed under ultrasound radiation, and are characterized by HR‐MS, FT‐IR and 1H and 13C NMR spectroscopy. The reaction has simple operation, metal‐free catalysis, acid or base free catalysis. As a green catalyst, vitamin B1 is found to possess favorable catalytic activity and reusability for the condensation reaction. 5‐(2‐Hydroxy‐3‐methoxybenzylidene)‐3‐methylisoxazol‐5(4H)‐one as a metal ion fluorescent probe, has excellent selectivity to Sr2+ and exhibits obvious discoloration. Fe2+ quenches the fluorescence of the ligand 3‐methyl‐4‐(2,3,4‐trihydroxybenzylidene)isoxazol‐5(4H)‐one, and exhibits an obvious color change.