Ethynylpyridine → 4-Nitro-2-(pyridin-2-ylethynyl)aniline

Participants

Reaction Conditions

Reaction Steps

To the solution of 2-iodo-4-nitroaniline (3.0 g, 11 mmol) in DMF (60 mL) and Et3N (60 mL) was added 2-ethynylpyridine (3.0 g, 45 mmol), Pd(PPh3)2Cl2(600 mg) and CuI (200 mg) under N2. The reaction mixture was stirred at 60° C. for 12 h. The mixture was diluted with water and extracted with dichloromethane (3×100 mL). The combined organic layers were washed with brine, dried over anhydrous Na2SO4 and concentrated in vacuum. The residue was purified by chromatography on silica gel (5-10% ethyl acetate/petroleum ether) to afford 4-nitro-2-(pyridin-2-ylethynyl)aniline (1.5 g, 60%). 1 H NMR (300 MHz, CDCl3) δ 8.60(s, 1 H), 8.13 (d, J=2.1 Hz, 1 H), 7.98(d, J=1.8, 6.9 Hz, 1 H), 7.87-7.80(m, 2 H), 7.42-7.39(m, 1 H), 7.05 (brs, 2 H), 6.80(d, J=6.9 Hz, 1 H).

Provenance & Evidence