METHODS WITHOUT USING METAL CATALYST AND HYDROGEN GAS FOR SELECTIVE REDUCTION OF ALDEHYDE GROUP TO METHYL GROUP IN VARIOUS SUBSTITUTED FURANS Russian patent published in 2024 - IPC C11C3/12 C07D307/36 C10L1/02 

FIELD: chemistry.

SUBSTANCE: invention relates to a method for selective reduction of an aldehyde group to a methyl group in substituted furans to obtain 5-methyl-substituted furans of general formula (I), where R¹ is selected from the group consisting of the following: a hydrogen atom, hydroxymethyl, alkyl, hydroxy group, aldehyde group, halogen atom, ester group, carboxyl, nitro group, amino group, amide, substituted amino group, alkoxy/ether bridges, sulphur derivatives, phosphorus derivatives, and an aryl and heteroaryl functional group; and R² and R³ are selected from the group consisting of the following: a hydrogen atom, alkyl and aryl, where said method comprises the steps of: i) reacting an amine compound and an inorganic base with a substituted furfural of formula (II) in a solvent to obtain in situ the corresponding imine compound; ii) in situ reduction of the generated imine from step (i) under basic conditions in a solvent to obtain 5-methyl-substituted furans of general formula (I); iii) extraction of methyl-substituted furans of general formula (I).

EFFECT: proposed method is convenient, efficient and scalable.

13 cl, 9 ex