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Comparative Example 2-11-(2',2',2'-Trichloroethyl)-2,4-dichloro-5-methylbenzene; At room temperature, 7.04 g [0.04 mol] of 2,4-dichloro-5-methylaniline are introduced into 28 ml of conc. hydrochloric acid, the mixture is cooled to -5 to 0 C. and a solution, cooled to 0 C., of 3.31 g [0.048 mol] of NaNO2 in 80 ml of water is added dropwise within 60 minutes. Subsequently, the mixture is stirred at -5 to 0 C. for 15 minutes. Subsequently, 3.23 g [0.024 mol] of copper(II) chloride are added. To this mixture is added dropwise, at 0 C. within 30 minutes, a solution of 38.8 g [0.4 mol=10 molar equivalents] of vinylidene chloride in 130 ml of acetone. The mixture is allowed to come to room temperature with good stirring and left to react for another 3 hours. The reaction mixture is diluted with 100 ml of water and extracted twice with 70 ml each time of MTBE. The combined organic phases are washed with 30 ml of water, dried over sodium sulphate and concentrated under reduced pressure. This gives 12.3 g of oil which, according to GC-MS, contains 64.05 area % of 1-(2',2',2'-trichloroethyl)-2,4-dichloro-5-methylbenzene. This corresponds to a yield of 67.4% of theory.The GC-MS shows, as by-products, 5.7 area % of Sandmeyer product and 23.8 area % of 1,5-dichloro-2-methyl-4-(2',2',4',4',4'-pentachlorobutyl)benzene. |