SU388556A1 - The method of obtaining 3,4,6-trichloropyridazine - Google Patents

Description

This invention relates to a simpler method for the preparation of 3,4,6-trichloropyridazine, which finds the right one - a change in the pharmaceutical and chemical industry.

Pick up; 1 method of obtaining 3,4,6-trichloropyridazy chlorination m 3,6-dichlorium iridazha. Chlorine in the presence of 5% of aluminum chloride 140 ° C. The reaction mixture is treated with benzene, and from benzene plant-Eora 3,4 , 6-trichloroiridase extract aluminum chloride with a 10% solution of sodium chloride. The yield of 3,4,6-trichloroiridazine 84%.

However, this method is characterized by the use of high temperatures for the development of the reaction; the necessity of extracting the reaction mass, containing 3,4,6-trichloroiridazine, which has a skin-blistering effect; after extraction, a significant amount of saline solution remains, containing a small amount of 3,4,6-tr: ichlor iridazia, which must not be disposed of by draining into the sewer system.

In order to eliminate this and simplify the process, they propose a method of obtaining 3,4,6 trichlori. Pyridine, according to which iron oligonyl ions are used as a catalyst, the reaction is carried out at 100 ° C and the product is extracted with a solvent, for example, dichloroethane. Yield 95%.

.Example. In the flask, the supply of: Nu1O fur;); With a primary stirrer, a cold 1 1 com, a gas pipeline with a three-way pipe connected to the absorption pot with a 40% caustic soda, a thermometer and a chlorine tube, 50 g 3 , b-dichloropyr; 1dazine and 0.5 g of iron powder. The mixture is heated to 100 ° C and dry chlorine gas is passed through with stirring.

The end of the reaction is checked with the iod: cata-bu. Magge-congo, which, upon recollection: GI1I in: -3l, hydrogen, and hydrogen chloride and chlorine leakage, is discolored.

The reaction mass is cooled to 80 ° C, 80 ml of dichloroethane are poured in and mixed for 5-10 minutes. The solution is poured off, and Onnlki gland1p 5e is washed twice with dichloroethane, 1 or 10 ml, attached to the main solution.

0 Dichloroethane is distilled off in a vacuum, and the residue is distilled. 58.5 g (95.1%) of 3.4,6-trichloropyridium are obtained with a temperature of 132 ° C and 19 mm and a melting point of 57-58 C.

Formula and 3 about b e e} 1

1. The method of producing 3,4,6-trichlorop11 rpdazine by chlorinating 3,6-dichloro Mridazi 1a with chlorine gas in the presence of gas; Za30 mountain when heated, followed by V1z1de ;; s34

And uevieBoro product, azzestry-m cnoco6oiw, qi: and extract with a solvent, for example, for the purpose of simplified chloroethane.

Process of the process, as tch; atalnzator is-2. The method according to claim 1, wherein

iron filings are used, and the pea product is used for the reaction at 100 ° C.

388556