Cesium carbonate → 4-(Pyridin-3-yl)-2-nitroaniline

Temperature

65 °C

4-Amino-3-nitrophenylboronic acid pinacol ester (1.60 g, 6.06 mmol), 3-bromopyridine (1.10 g, 6.96 mmol), cesium carbonate (3.33 g, 10.22 mmol) and 1,1′-bis(diphenylphosphino)ferrocene-palladium(II) dichloride DCM complex (491 mg, 0.60 mmol) were suspended in dimethylformamide (20 mL). The solution was degassed by vacuum several times and placed in an argon atmosphere. It was then heated to 65° C. for 6 hr. After cooling, EA (100 mL) and water (40 mL) were added. When additional water (50 mL) was added to the organic layer, a precipitate was formed in the separatory funnel. The biphasic solution was filtered, and the filtrate was transferred to the separatory funnel and separated. The organic phase was washed twice with water (50 mL each), then with brine, and then dried with sodium sulfate and concentrated under reduced pressure to give 2-nitro-4-(pyridin-3-yl)benzenamine (1.18 g). 2-Nitro-4-(pyridin-3-yl)benzenamine (700 mg, 3.26 mmol) in 1:1 ethanol/EA (40 mL) was hydrogenated at atmospheric pressure with 10% palladium on carbon (90 mg, 0.08 mmol) at room temperature for 2 days. Filtration and concentration under reduced pressure gave 4-(pyridin-3-yl)-benzene-1,2-diamine (621 mg).

1. customThe solution was degassed by vacuum several times
2. temperatureAfter cooling
3. additionEA (100 mL) and water (40 mL) were added
4. additionWhen additional water (50 mL) was added to the organic layer
5. customa precipitate was formed in the separatory funnel
6. filtrationThe biphasic solution was filtered
7. customseparated
8. washThe organic phase was washed twice with water (50 mL each)
9. dry with materialwith brine, and then dried with sodium sulfate
10. concentrationconcentrated under reduced pressure

ORD record

ord-2680b3a221cf4f9182bb0c1dc68ca589

Source dataset

uspto-grants-2012_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08129396B2