Hydrochloric Acid → 6-Chloro-2,4-dinitroaniline

Participants

Reaction Steps

183 parts of 2,4-dinitroaniline are suspended in 220 parts of water and the suspension is ground. 800 parts of 14.2 % hydrochloric acid are charged to a reactor. The hydrochloric acid may originate from a previous batch and, after isolation of the product, is recycled to the reactor. The aqueous suspension of dinitroaniline and a total of 78 parts of chlorine are then added simultaneously to the hydrochloric acid over 240 minutes, with the addition of dinitroaniline being made over 240 minutes, whereas the chlorine is added for a further 20 minutes, i.e. over a total time of 260 minutes. The batch is allowed to react for 30 minutes and excess chlorine is expelled over a further 30 minutes. The product is then isolated by filtration, washed until neutral and dried, affording 204 parts of 2-chloro-4,6-dinitroaniline, corresponding to a yield of 94 %. Melting point: 157.5° C. (lit. : 157°-159° C.). Analysis of gas chromatography shows that the product has the same retention time as authentic material. Comparable results are obtained by carrying out the reaction at 40° C.

Provenance & Evidence