2,3,5-Trimethylpyridine → 3,5-Dimethylpyridine-2-carbaldehyde

Participants

Reaction Conditions

Reaction Steps

In dichloromethane (15.0 ml), 2,3,5-trimethyl-pyridine (manufactured by Tokyo Kasei Kogyo Co., Ltd.) (1.29 g) was dissolved. After having been cooled to 0° C., the reaction solution was added with m-chloroperbenzoic acid (2.53 g), followed by stirring at room temperature for 1.5 hours. The reaction solution was added with a 1 mol/l sodium hydroxide aqueous solution and then subjected to extraction with chloroform. Subsequently, the organic layer was washed with a saturated saline solution and dried with anhydrous sodium sulfate. The drying agent was filtrated out and the solvent was then distilled off, followed by dissolving the resultant residue in dichloromethane (25.0 ml). The reaction solution was added with trifluoroacetic anhydride (2.8 ml) and the whole was refluxed under heating for 3.5 hours. After the reaction solution was cooled to room temperature, the solvent was distilled off. The resultant residue was dissolved in methanol (60.0 ml). After having been cooled to 0° C., the reaction solution was added with a 12.5% sodium methoxide/methanol solution to adjust the solution to pH 10, and the whole was stirred at room temperature for 16.5 hours. After the solvent was distilled off, the residue was added with distilled water and subjected to extraction with chloroform. The organic layer was washed with a saturated saline solution and dried with anhydrous sodium sulfate. The drying agent was filtrated out and the solvent was then distilled off, followed by dissolving the residue in chloroform (30.0 ml). The reaction solution was added with manganese dioxide (chemically processed product) (6.10 g) and then stirred at room temperature for 18 hours. The reaction solution was filtrated through Celite. The solvent in the filtrate was distilled off and the resultant residue was then purified through silica gel column chromatography (chloroform/ethyl acetate), thereby obtaining the subject compound (1.14 g) as a yellow oily substance.

Provenance & Evidence