| 摘要 |
<p>1,053,793. Polychloronitrobenzenes and tetrachloro - o - phenylenediamine. FISONS PEST CONTROL Ltd. Oct. 23, 1963 [Nov. 10, 1962], No. 40957/63. Divided out of 1,053,792. Heading C2C. 1,2,3,4-Tetrachloro-5-nitrobenzene is made by chlorinating 1,2,4-trichloro-5-nitrobenzene by treatment with chlorine in the presence of chlorosulphonic acid and iodine. The chlorination is preferably effected in the temperature range 30-150‹ C., the chlorosulphonic acid being present in amount comprising 0À2 to 4À0 mols., and the iodine 0À15-2% by weight, on the basis of the 1,2,4-trichloro-5-nitrobenzene. The latter may be made by mono-nitration of 1,2,4-trichlorobenzene with nitric acid or with a mixture of nitric acid and sulphuric acid. 1,2,3,4 - tetrachloro - 5,6 - dinitrobenzene may be made by nitration of the 1,2,3,4-tetrachloro- 5-nitrobenzene using mixed nitric and sulphuric acids at elevated temperature, preferably using 80-100% HNO 3 and 90-100% H 2 SO 4 , in the range 50‹ to 115‹ C. Tetrachloro-o-phenylenediamine may be made by reducing 1,2,3,4-tetrachloro-5,6-dinitrobenzene, for example with stannous chloride and hydrochloric acid or an alcohol, with sodium hydrosulphite, or with zinc and an acid.</p> |
