6-Methyl-2,3,4,5-tetrahydro N-oxide (CAS NO.: ), with other names as Pyridine, 2,3,4,5-tetrahydro-6-methyl-, 1-oxide, could be produced through the following synthetic routes.

In a 500-mL, three-necked, round-bottomed flask equipped with a 100-mL pressure-equalizing dropping funnel, a thermometer, and a magnetic stirring bar is placed 2.64 g (8.00 mmol) of sodium tungstate dihydrate. After the flask is flushed with nitrogen, 40 mL of water and 23.5 mL (200 mmol) of 2-methylpiperidine are added. The flask is cooled with an ice-salt bath to -5°C (internal temperature) and 45.0 mL (440 mmol) of 30% aqueous hydrogen peroxide solution is added dropwise over a period of ca. 30 min. During the period of addition the reaction mixture should be carefully kept at a temperature below 20°C. The cooling bath is removed, and the mixture is stirred for 3 hr. Excess hydrogen peroxide is decomposed by adding ca. 3 g of sodium hydrogen sulfite with ice cooling. The solution is saturated by adding ca. 25 g of sodium chloride and extracted with ten 200-mL portions of dichloromethane. Combined organic extracts are dried over anhydrous sodium sulfate. The drying agent is removed by filtration, and the solvent is removed by a rotary evaporator keeping the temperature at 40°C to give a pale yellow oil (20.0–22.0 g), which may be sufficiently pure for some applications. Purification of the nitrone is achieved by column chromatography on 300 g of silica gel packed in 97:3 chloroform/methanol in a 4.8-cm × 70-cm column. The product is applied to the column in 10 mL of chloroform and the column is eluted with 97:3 chloroform/methanol. After twenty 100-mL fractions are collected, the eluent is changed to 8:2 chloroform/methanol, and another ten 100-mL fractions are collected and analyzed by thin layer chromatography. Combination of fractions 16–30 and evaporation provides 14.0–15.7 g (62–70%) of pure 6-methyl-2,3,4,5-tetrahydropyridine N-oxide as a pale yellow oil.