反应详情

温度

-78 °C

The mixture of 5-(4-tert-butoxycarbonyl-piperazin-1-yl)-imidazo[4,5-b]pyridine-3-carboxylic acid tert-butyl ester (600 mg, 1.49 mmole), methyl-2-bromo-isonicotinate (321 mg, 1.49 mmole), and tetrahydrofuran (5 ml) was cooled to −78° C. Lithium diisopropylamide (2N, 2.23 ml, 4.46 mmole) was added slowly. Reaction mixture was stirred at −78° C. for 2 hours. Reaction was quenched with water and extracted with EtOAc. EtOAc layer was concentrated and crude product was purified by using silica gel chromatography, eluting with 0% to 40% of EtOAc in CH2Cl2 to afford 4-[2-(2-bromo-pyridine-4-carbonyl)-3H-imidazo[4,5-b]pyridine-5-yl]-piperazine-1-carboxylic acid tert-butyl ester (120 mg, 16.6%). 1H NMR (400 MHz, CD2Cl2) δ 1.58 (s, 9H), 3.59 (m, 4H), 3.74 (m, 4H), 6.89 (d, J=9.03 Hz, 1H), 8.03 (d, J=9.03 Hz, 1H), 8.39 (d, J=5.03 Hz, 1H), 8.61 (d, J=5.02 Hz, 1H), 8.67 (s, 1H). MS(ESI) m/z 488 [M+1].

1. customReaction mixture
2. customReaction
3. customwas quenched with water
4. extractionextracted with EtOAc
5. concentrationEtOAc layer was concentrated
6. customcrude product was purified
7. washeluting with 0% to 40% of EtOAc in CH2Cl2