Water → 3,3',5,5'-Tetrachlorohydrazobenzene

To a stirred solution of 50% NaOH (20 mL) was added 3,5-dichloronitrobenzene (38.4 g, 200 mM) and the resulting solution was heated at 60° C. Zinc dust (15 g, 230 mM) was added in portions in such a way as to maintain the reaction temperature between 70° and 80° C. The resulting slurry was then diluted with 12 mL of 50% NaOH followed by 35 mL of water. An additional amount of zinc dust (20 g, 310 mM) was added in a single portion and the resulting suspension was heated to 70°-80° C. for 3 hours. The reaction mixture was then cooled to room temperature and the solid obtained was extracted with ethyl acetate. The extracts were dried over Na2SO4 and concentrated to 1/2 the original volume. An orange solid precipitated which was removed by filtration and discarded. The filtrates were diluted with hexane which caused a precipitate. This was then filtered, providing the titled compound as a yellow solid (11.3 g, 35%). NMR (d6 -DMSO): 8.38 (s, 2H), 6.82 (s, 2H), 6.67 (s, 4H). MS(CI): 323(M+1).

1. temperatureto maintain the reaction temperature between 70° and 80° C
2. temperaturethe resulting suspension was heated to 70°-80° C. for 3 hours
3. temperatureThe reaction mixture was then cooled to room temperature
4. customthe solid obtained
5. extractionwas extracted with ethyl acetate
6. dry with materialThe extracts were dried over Na2SO4
7. concentrationconcentrated to 1/2 the original volume
8. customAn orange solid precipitated which
9. customwas removed by filtration
10. additionThe filtrates were diluted with hexane which
11. filtrationThis was then filtered

ORD record

ord-e4310654d0144ce1b39bf3f8320d79e1

Source dataset

uspto-grants-1997_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05652239