Phosphorus trichloride → 4-bromo-2,2'-bipyridine

Beteiligte Stoffe

Reaktionsschritte

To a stirred suspension of 4-bromo-2,2′-bipyridyl-N-oxide in 60 mL CHCl3 was added 12 mL PCl3 at room temperature. The mixture was refluxed for 2 h under N2 and then cooled to room temperature. The reaction mixture was poured into 100 mL ice/water. The aqueous layer was separated and saved. The CHCl3 layer was extracted three times with H2O (3×60 mL) and then discarded. The combined aqueous solution was neutralized with NaHCO3 powder to about pH 7-8. The resulting white precipitate was collected by suction filtration, washed with H2O (30 mL) and then dried under vacuum at 50° C. for 24 h. Yield: 85%.

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