Access to arylmethylidene-isoxazol-5(4H)-ones and benzylidenemalononitriles promoted by imidazole as an efficient organocatalyst

Synthesis of Arylmethyledene-isoxazole-5(4H)-ones have been achieved via one pot reaction of various aromatic aldehydes, hydroxylamine hydrochloride and ethyl acetoacetate promoted by imidazole as an efficient organocatalyst in ethanol: water medium. In mild basic condition, this protocol is useful for easy access to arylmethylidene-isoxazol-5(4H)-ones, which are having potential utility in the field of medicinal chemistry. Encouraged by this, the same protocol has been utilized for the synthesis of benzylidenemalononitriles by the Knoevenagel condensation reaction between various aldehydes and malonitrile. Both the protocols offer cost effectiveness and operational simplicity for the synthesis of isoxazoles and benzylidenemalononitriles in environment-friendly reaction conditions.