Reaction #2487418

Reaction equation

2-([1,1′-Biphenyl]-3-yl)-5-bromo-4-methylpyridine

2,4,6-trimethyl-1,3,5,2,4,6-trioxatriborinane

potassium phosphate tribasic monohydrate

toluene

→

product

Yield 87.0%

2-([1,1′-biphenyl]-3-yl)-4,5-dimethylpyridine

Yield 87.0%

Solvents

water

Conditions

Workup

1. 1
   OtherThe reaction mixture was degassed with nitrogen for 20 minutes
2. 2
   Temperatureheated
3. 3
   Temperatureto reflux for 24 h
4. 4
   TemperatureAfter cooling
5. 5
   Otherthe organic layer was separated
6. 6
   Extractionthe aqueous layer extracted 3×50 mL with dichloromethane
7. 7
   Dryingdried over sodium sulfate
8. 8
   Otherevaporated
9. 9
   OtherThe crude product was chromatographed on silica gel with 5% dichloromethane in hexane

Procedure

2-([1,1′-Biphenyl]-3-yl)-5-bromo-4-methylpyridine 11.5 g (35.5 mmol), 2,4,6-trimethyl-1,3,5,2,4,6-trioxatriborinane (5.57 g, 44.3 mmol), dicyclohexyl(2′,6′-dimethoxy-[1,1′-biphenyl]-3-yl)phosphine (1.2 g, 2.84 mmol), Pd2dba3 (0.650 g, 0.709 mmol) and potassium phosphate tribasic monohydrate, 250 mL toluene and 25 mL of water were placed in flask under nitrogen. The reaction mixture was degassed with nitrogen for 20 minutes and heated to reflux for 24 h. After cooling, the organic layer was separated and the aqueous layer extracted 3×50 mL with dichloromethane, dried over sodium sulfate and evaporated. The crude product was chromatographed on silica gel with 5% dichloromethane in hexane to give 8.0 g (87%) of the product. The product was confirmed by NMR and GC/MS.

Source