Lipase Catalyzed One-Pot Synthesis of 3-Methyl-4-(Hetero) Arylmethyleneisoxazole-5(4H)-Ones under Aqueous Conditions

Present work reports an efficient and environmentally benign approach for the synthesis of isoxazole-5(4H)-ones derivatives using lipase as biocatalyst. The one-pot multicomponent reaction of aldehyde, ethyl acetoacetate, and hydroxylamine hydrochloride at room temperature gives a 3-methyl-4-(hetero) arylmethylene isoxazole-5(4H)-ones derivatives using water as a solvent. The present protocol has many advantages such as shorter reaction time, excellent yields of products, easy work-up procedure, wide substrate scope tolerance, economical, etc. Moreover, the catalyst (lipase) was recovered and can be reused (up to four to five cycles) without significant loss of its catalytic activity. [GRAPHICS] .