Hydrochloric Acid → 5-Bromo-o-toluidine

Temperature

100 °C

4-Bromo-2-nitrotoluene (13.5 g, 62.5 mmol) and granulated tin (11.25 g, 95 mmol) were placed in a round bottomed flask to which concentrated hydrochloric acid (25 ml) was added in small (ca 5 ml) aliquots. A gentle reaction was evident during this addition period. When all the acid had been added the reaction mixture was heated and stirred at about 100° C. for 4 h. The solution was allowed to cool and a solution of sodium hydroxide (18.75 g) in water (32 ml) was added. The solution was heated at 100° C. for 1 h. After cooling, water (200 ml) was added and the solution was filtered. The aqueous filtrate was extracted with diethyl ether (200 ml). The filtered salts were also extracted with diethyl ether (200 ml). The combined organic layers were dried, filtered and evaporated to leave an oil. This was purified by distillation (112° C. at 4 mm Hg) to leave the title compound (6.76 g, 58%).

1. additionwas added in small (ca 5 ml) aliquots
2. customA gentle reaction
3. additionwas evident during this addition period
4. additionWhen all the acid had been added the reaction mixture
5. temperaturewas heated
6. temperatureto cool
7. temperatureThe solution was heated at 100° C. for 1 h
8. temperatureAfter cooling
9. filtrationthe solution was filtered
10. extractionThe aqueous filtrate was extracted with diethyl ether (200 ml)
11. extractionThe filtered salts were also extracted with diethyl ether (200 ml)
12. customThe combined organic layers were dried
13. filtrationfiltered
14. customevaporated
15. customto leave an oil
16. distillationThis was purified by distillation (112° C. at 4 mm Hg)

ORD record

ord-df46ac959792414ba72abd97c75eeefd

Source dataset

uspto-grants-1994_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05302390