4-Bromotoluene → 2-Methyl-6-(4-methylphenyl)pyridine

Magnesium (1.6 g) and p-bromotoluene (10.2 g) in 100 ml of tetrahydrofuran were stirred and warmed until the reaction commenced. When the exothermic reaction had finished, the mixture was refluxed for 1 hour. In a separate flask, a solution of palladium(II)bis(triphenylphosphine)dichloride (1.4 g) in 60 ml of tetrahydrofuran was prepared, and 4 ml of DIBAL (1M in toluene) added, followed by 2-bromopicoline (6.9 g). To this mixture, the magnesium reagent prepared above was added dropwise, causing an exothermic reaction. The reaction mixture was stirred overnight at room temperature, and then quenched by addition of ether/water. The mixture was washed with dilute hydrochloric acid, water, and then saturated brine. The organic layer was separated, dried over sodium sulfate, the solvent evaporated under reduced pressure, and the residue chromatographed on silica gel, eluting with 30-50% methylene chloride in heptane, to yield 4.5 g of 2-(4-methylphenyl)-6-methylpyridine, a compound of Formula (31), as an oil.

1. temperaturewarmed until the reaction commenced
2. customWhen the exothermic reaction
3. temperaturethe mixture was refluxed for 1 hour
4. additionabove was added dropwise
5. customan exothermic reaction
6. customquenched by addition of ether/water
7. washThe mixture was washed with dilute hydrochloric acid, water
8. customThe organic layer was separated
9. dry with materialdried over sodium sulfate
10. customthe solvent evaporated under reduced pressure
11. customthe residue chromatographed on silica gel
12. washeluting with 30-50% methylene chloride in heptane

ORD-Eintrag

ord-69fa0b5b080547718031b61d69c72bad

Quelldatensatz

uspto-grants-1995_06

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US05428037