SU915423A1 - Process for producing 1-aminotetrazole - Google Patents

Description

The invention relates to an improved method for producing 1-aminotetrazole, which finds use as a starting product in the synthesis of drugs, explosives and photographic materials. A method of obtaining 1-aminotetrazole by the interaction of tetrazole and hydroxylamine-O-sulfonic acid in an aqueous alkaline solution, followed by separation of the resulting mixture of 1- and 2-amino tetrazole [1].

The yield of the target product ~ 25%.

The disadvantages of the method are the low yield of the target product and the difficulty of separating it from the mixture with 2-aminotetrazole.

The closest in technical essence to the proposed method is the preparation of 1-aminotetrazole, ₂ zaklyuchayu- about schiysya that 1 mol benzalgidrazona reacted with 4 mol orthoformic ester at 140 "C in the presence of catalytic amounts of sulfuric acid selected benzal-2-ethoxymethyl - 25 Lengidrazone is treated with sodium azide at a molar ratio of 1: 4 in acetic acid at room temperature for 24 hours, followed by isolation of the desired product by hydrolysis to form

2

1-benzylideneamine tetrazole hydrochloric acid and steam distillation [2]. The yield of the target product on the original oenzalgidrazon ~ 37%.

The disadvantages of this method are its complexity, associated with its multi-stage, duration, high consumption of ortho-formic ester and sodium azide, a relatively low yield of the target product.

The purpose of the invention is to simplify the process, allowing the process to be carried out in one stage, to reduce the duration of the process and the consumption of ortho-formic ether and sodium azide, to increase the yield of the target product.

This goal is achieved with the implementation of the method of obtaining 1-amiotetrazole by simultaneous mixing of benzalhydrazone, ort-formic ester of sodium pazide and carrying out the process at 75–85 ° С in acetic acid.

The proposed method allows to carry out the process in one stage, eliminate the stage of isolation and purification of Beisol-2 ethoxylmethylene hydrazone, reduce the duration of the process from 24 to 2.5-3 hours, reduce the consumption of ortho-formic ether and sodium azide, increase the yield of the target product to ~ 62%.

3

Example. To a mixture of 60 g (0.5 mol) of benzalgndrazone, 39 g (0.6 mol) of sodium azide and 133.2 g (0.9 mol) of the organic ether form are poured with stirring 250 ml of acetic acid and stirred for 2.5 h. at 75-85 ° C. The reaction mass is poured with stirring into 1.3 liters of water, the precipitated precipitate is filtered and washed with water. 250 ml of water and 120 ml of concentrated hydrochloric acid are added to the obtained product and distilled with steam until the solution is clear. The residue is neutralized, evaporated, extracted with ethyl acetate and the extract is dried with magnesium sulfate. After 1 distillation of the solvent, 26.2 g (61.8%) of 1-aminotetrazole are obtained. Benzaldehyde derivative: T _pl . 92-93 ° C. The presence of clear absorption bands in the IR spectrum (txn ₂ : 3340, 3215 cm ^-1 ; bmn ₂ 1623 cm ^-1 ; 2 tsn 3155 cm ^-1 ; δ rings 975,1105,1190 s \ g ') confirms the structure of the product.

915423

four

Claims (1)

Claim The method of obtaining 1-aminotetrazole based on benzalhydrazone, ortho-formic 5 ether and sodium azide, using acetic acid and hydrolysis of the resulting 1-benzylidene aminotetrazole with hydrochloric acid and steam distillation, in order to increase the yield of the target product and simplify process, simultaneously mix the above reagents and the process is carried out at 75-85 ° C in acetic acid.