2,6-Dibromopyridine → 6-Bromo-pyridine-2-carboxylic acid tert-butylamide

Beteiligte Stoffe

Reaktionsschritte

2,6-Dibromopyridine (40 g, 170 mmol) in THF (200 mL) was added dropwise over 1 hr to a cooled (−78 C) solution of n-butyllithium (2.0M in pentane, 85 mL, 170 mmol) in THF (100 mL) under a nitrogen atmosphere. The mixture was allowed to stir for an additional 15 min, then tert-butyl isocyanate was added dropwise over 5 min. The resulting reaction mixture was allowed to warm slowly to room temperature overnight before quenching with saturated ammonium chloride solution (200 mL) and extracting with ethyl acetate (2×100 mL). The combined organics were dried (MgSO4) and evaporated in vacuo to yield the cude product A466.1 (42.4 g) as a dark brown oil which was used immediately without further purification. HPLC YMC S-5 4.6×33 mm (2 min grad): retention time 1.76 min, M+H+=203.08

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