1-Bromo-4-nitrobenzene → 4-Bromo-3-(4-nitrophenyl)pyridine

Participants

Reaction Steps

A solution of LDA (2.86 mL, 5.14 mmol) in THF (2.5 mL) was transferred to a solution of 4-bromopyridine hydrochloride (500 mg, 2.57 mmol) in THF (5 mL) at −78° C. and stirred for 30 min. Zinc chloride (350 mg, 2.57 mmol) in THF (2.5 mL) was added to the above reaction mixture. A precipitate was formed and the mixture was allowed to warm to room temperature. Next, 1-bromo-4-nitrobenzene (1039 mg, 5.14 mmol) and tetrakis(triphenylphosphine)palladium(0) (149 mg, 0.129 mmol) were added, and the reaction mixture was heated to reflux for 3 hours and then cooled to room temperature. The resulting reaction mixture was diluted with saturated solution of ammonium chloride (25 mL) and extracted with EtOAc (2×25 mL). The combined organics were washed with brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The crude material was purified by silica gel chromatography (40 g ISCO column, eluting with 0% to 50% EtOAc in CH2Cl2) to afford Intermediate 13A (300 mg, 1.023 mmol, 10.47% yield) as a pale yellow solid. MS (ES): m/z=280.9 [M+H]+. 1H NMR (400 MHz, DMSO-d6) δ ppm 7.84 (s, 1 H) 7.87 (s, 1 H) 7.97 (d, J=5.29 Hz, 1 H) 8.41 (s, 1 H) 8.43 (s, 1 H) 8.57 (d, J=5.29 Hz, 1 H) 8.66 (s, 1 H).

Provenance & Evidence