17028-61-4

2-Hydroxy-3-methoxy-5-nitrobenzaldehyde is used for the syntheses of zinc-selective spiropyran-based fluorescent and photoregenerable receptor, (E)-2,4-dihydroxy-N?-(2-hydroxy-3-methoxy-5-nitrobenzylidene)benzohydrazide dihydrate, ethyl 4-(8-methoxy-3?,3?-dimethyl-6-nitrospiro[chromene-2,2?-indoline]-1?-yl)butanoate and 1-(3-carbomethoxypropyl)-3-3-dimethyl-8-methoxy-6-nitrospiro[2H-1]-benzopyran-2,2-indoline.

General procedure for the synthesis of 2-hydroxy-3-methoxy-5-nitrobenzaldehyde from o-vanillin: o-vanillin (94 mg, 1 mmol) was dissolved in 3 mL of glacial acetic acid in a 50 mL test tube. Subsequently, solid Y(NO3)3-6H2O (383 mg, 1 mmol) was added to the solution and the reaction mixture was shaken continuously for 10 min at room temperature. The reaction process was monitored by thin layer chromatography (TLC) and the unfolding agent was petroleum ether with 10% ethyl acetate. Upon completion of the reaction, 30 mL of ice-cold water was added to the reaction mixture and allowed to stand for 15 min. The precipitated solid product was collected by filtration and washed with cold water. The solid product obtained was used directly for analysis without further purification. Detailed experimental methods for the synthesis of compounds 2a-2e are described in Supporting Information.

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