Stannous chloride dihydrate → 4-Iodobenzene-1,2-diamine

Temperature

65 °C

4-Iodo-2-nitroaniline (35.2 g, 0.133 mol) was added in batches via an open funnel over 25 min to a heated (65° C.) mixture of SnCl2.2H2O (106.86 g, 0.465 mol) and 12N HCl (200 ml). An additional 12N HCl (30 ml) was added and the reaction mixture was heated at 65° C. for an additional 1 h, and stirred at room temperature for 1 h. It was placed in a refrigerator for 15 h, and the precipitate was filtered. The resultant solid was transferred into a flask containing water (210 ml), cooled (ice/water), and a solution of NaOH (aq) (35 g in 70 ml of water) was added to it over 10 min with stirring. The cooling bath was removed, and vigorous stirring was continued for 45 min. The mixture was filtered and the solid was washed with water and dried in vacuo to provide 4-iodobenzene-1,2-diamine as a tan solid (25.4 g). The product was used in the next step without further purification. 1H NMR (DMSO-d6, δ=2.5 ppm, 500 MHz): 6.79 (d, J=2, 1H), 6.63 (dd, J=1.9, 8.1, 1H), 6.31 (d, J=8.1, 1H), 4.65 (br s, 2H), 4.59 (br s, 2H). LC/MS: Anal. Calcd. for [M+H]+ C6H8IN2: 234.97; found: 234.9.

1. temperaturea heated
2. waitIt was placed in a refrigerator for 15 h
3. filtrationthe precipitate was filtered
4. customThe resultant solid was transferred into a flask
5. additioncontaining water (210 ml)
6. temperaturecooled (ice/water)
7. additiona solution of NaOH (aq) (35 g in 70 ml of water) was added to it over 10 min
8. stirringwith stirring
9. customThe cooling bath was removed
10. stirringvigorous stirring
11. waitwas continued for 45 min
12. filtrationThe mixture was filtered
13. washthe solid was washed with water
14. customdried in vacuo

ORD record

ord-b5edebb6caf5485ea9e5487df528521d

Source dataset

uspto-grants-2013_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08394968B2