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A green and efficient method for the construction of functionalized 2,3-dihydrothiophene derivatives in water was reported. In this work, Novozym 435 acted as a remarkable biocatalyst in catalyzing the four-component reaction of aldehydes, malonitrile or ethyl cyanoacetate, 1,3-thiazolidinedione, and amines under mild conditions. Excellent yields (85–95%) of all the corresponding products could be obtained in reasonable reaction time. Moreover, Novozym 435 could be reused for six cycles with a yield of at least 80%. The rationality of this multicomponent reaction mechanism was also verified via control experiments. [ABSTRACT FROM AUTHOR]

In this study, supercritical carbon dioxide (ScCO2), which is a sustainable and green solvent, was used as a reaction medium in the lipase‐catalyzed synthesis of anthrone‐functionalized benzylic amines for the first time. We synthesized the target compounds via a lipase‐catalyzed multicomponent cascade reaction of aldehydes, sulfonamides, and anthrones in ScCO2. The reaction can be accomplished in good‐to‐excellent yields (77 %–95 %) and can exhibit good functional group tolerance. In brief, the reaction was characterized by step economy, metal‐free conditions, environmentally friendly solvents, and biocatalysts. [ABSTRACT FROM AUTHOR]

• Hemin is used as a highly efficient catalyst for the controlled synthesis of α-aminonitriles and α-iminonitriles. • High yields of the desired products were obtained with good functional group tolerance. • This work extends the application of Hemin in organic synthesis. We report an efficient and controlled oxidative cyanation approach for the synthesis of α-aminonitriles and α-iminonitriles in MeOH using Hemin (1 mol %) as a nontoxic and natural catalyst under room temperature. This work is the first report on the incorporation of a natural iron porphyrin complex as a redox catalyst for the oxidation of secondary amines. The significant features of this biomimetic strategy for the preparation of α-aminonitriles and α-iminonitriles include the use of MeOH as green and attractive solvent in an organic reaction, the use of ethyl cyanoformate as a benign cyanide source due to its mild conditions, environmentally friendly, the use of a biodegradable catalyst, no moisture sensitivity, simple workup procedure, and controllable, which all together make the current method attractive for academic research as well as industrial applications. [Display omitted] [ABSTRACT FROM AUTHOR]