Réaction #2320125

Équation de réaction

2-Bromo-5-methylpyridine

3-bromophenylboronic acid

triphenylphosphine

potassium carbonate

→

2-(3-bromophenyl)-5-methylpyridine

Rendement 68.1%

Solvants

ethyl acetate

water

ethylene glycol dimethyl ether

Conditions de réaction

Traitement

1. 1
   Autreequipped with a temperature probe
2. 2
   Températurereflux condenser, and a magnetic stir bar
3. 3
   TempératureThe solution was heated
4. 4
   Températureat reflux under nitrogen for 16 hr
5. 5
   AutreThe cooled reaction mixture
6. 6
   Autrewas then placed in a separatory funnel
7. 7
   ExtractionThe organic layer was extracted twice with a saturated solution of sodium chloride
8. 8
   Séchagedried over magnesium sulfate
9. 9
   Autreevaporated to dryness
10. 10
    workup.DISTILLATIONAfter the excess 2-bromo-5-methylpyridine was distilled off in vacuo at 110° C.
11. 11
    workup.DISTILLATIONthe 2-(3-bromophenyl)-5-methylpyridine was distilled at 200° C.
12. 12
    Autreto give 30.1 g (68.1% yield) of a slightly orange liquid, which
13. 13
    Autrewas used for the next step without further purification

Mode opératoire

2-Bromo-5-methylpyridine (46.1 g, 267 mmol), 3-bromophenylboronic acid (35.8 g, 178 mmol), palladium(II) acetate (1.00 g, 4.4 mmol), triphenylphosphine (4.67 g, 17.8 mmol), and potassium carbonate (67.8 g, 491 mmol) were mixed with 370 mL of ethylene glycol dimethyl ether and 245 mL of water in a 1000 mL round bottom flask equipped with a temperature probe, reflux condenser, and a magnetic stir bar. The solution was heated at reflux under nitrogen for 16 hr. The cooled reaction mixture was then placed in a separatory funnel, and 100 mL of ethyl acetate was added. The aqueous layer was discarded. The organic layer was extracted twice with a saturated solution of sodium chloride, dried over magnesium sulfate, and evaporated to dryness. After the excess 2-bromo-5-methylpyridine was distilled off in vacuo at 110° C., the 2-(3-bromophenyl)-5-methylpyridine was distilled at 200° C. to give 30.1 g (68.1% yield) of a slightly orange liquid, which was used for the next step without further purification.

Source