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

摘要

An 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 ~(13)C 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 Sr~(2+) and exhibits obvious discoloration. Fe~(2+) quenches the fluorescence of the ligand 3-methyl-4-(2,3,4- trihydroxybenzylidene)isoxazol-5(4H)-one, and exhibits an obvious color change.