반응 #800746

반응 방정식

2-Bromo-5-methylpyridine

phenylboronic acid

potassium phosphate tribasic monohydrate

toluene

→

5-methyl-2-phenylpyridine

수율 88.3%

용매

water

반응 조건

후처리

1. 1
   기타The reaction mixture was degassed with nitrogen for 20 min
2. 2
   온도the reaction mixture was refluxed for 18 h
3. 3
   온도After cooling
4. 4
   기타the organic layer was separated
5. 5
   추출the aqueous layer extracted with 3×50 mL dichloromethane
6. 6
   건조dried over sodium sulfate
7. 7
   기타evaporated
8. 8
   기타The crude product was chromatographed on silica gel with 75/25 (v/v) hexane/EtOAc
9. 9
   workup.DISTILLATIONdistilled on a Kugelrohr apparatus (150° C., 100 mbar)

실험 절차

2-Bromo-5-methylpyridine (30 g, 174 mmol), phenylboronic acid (25.5 g, 209 mmol), dicyclohexyl(2′,6′-dimethoxy-[1,1′-biphenyl]-2-yl)phosphine (2.86 g, 6.98 mmol) and potassium phosphate tribasic monohydrate (120 g, 523 mmol) were added to toluene (600 mL) and water (60 mL). The reaction mixture was degassed with nitrogen for 20 min. Pd2(dba)3 (3.19 g, 3.49 mmol) was added and the reaction mixture was refluxed for 18 h. After cooling, the organic layer was separated and the aqueous layer extracted with 3×50 mL dichloromethane, dried over sodium sulfate and evaporated. The crude product was chromatographed on silica gel with 75/25 (v/v) hexane/EtOAc and then distilled on a Kugelrohr apparatus (150° C., 100 mbar) to give 26 g (88%) of 5-methyl-2-phenylpyridine as a white solid. The product was confirmed by NMR and GC/MS. HPLC purity: 99.2%.

출처