Methyl iodide → 3,5-Dichloro-4-methylpyridine

Temperature

-75 °C

A solution of diisopropylamine (10.5 mL) in dry tetrahydrofuran (150 mL) is cooled to -75° C. and treated with a solution of butyl lithium in hexane (30 mL; 2.5 M) during 10 minutes. After stirring for 1 hour at -75° C. the mixture is treated with a solution of 3,5-dichloropyridine (10.8 g) in dry tetrahydrofuran (55 mL) and stirred for a further 30 minutes. It is then treated with methyl iodide (4.7 mL) in dry tetrahydrofuran (10 mL) during 10 minutes, and the solution is allowed to rise gradually to room temperature. After stirring for 2 hours, the mixture is treated with saturated aqueous sodium bicarbonate solution (50 mL), followed by diethyl ether (100 mL). The organic layer is washed with brine, dried and evaporated, and the resulting residue is subjected to flash chromatography, to give 3,5-dichloro-4-methylpyridine (10.6 g), m.p. 46-47° C.

1. stirringstirred for a further 30 minutes
2. customto rise gradually to room temperature
3. stirringAfter stirring for 2 hours
4. washThe organic layer is washed with brine
5. customdried
6. customevaporated

ORD record

ord-0945d740e935494b81d4e22c43d1f994

Source dataset

uspto-grants-2000_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06096768