Process for the preparation of bis-(1(2)H-tetrazol-5-yl)-amine monohydrate

1. A process for the preparation of Bis-(1(2)H-tetrazol-5-yl)-amine monohydrate of the formula (I), comprising:

combining sodium dicynamide and sodium azide in water to form a reaction mixture, and

adding a 6 molar solution of hydrochloric acid in the presence of a catalytic amount of boric acid into the reaction mixture for a period of 2-8 hours at 55° to 58° C.

2. The process for the preparation of Bis-(1(2)H-tetrazol-5-yl)-amine monohydrate of the formula (I) according to claim 1 , wherein the reaction achieves a yield of 90% to 93%.

3. The process for the preparation of Bis-(1(2)H-tetrazol-5-yl)-amine monohydrate of the formula (I) according to claim 1 , wherein the product is in fine crystalline nature.

4. The process for the preparation of Bis-(1(2)H-tetrazol-5-yl)-amine monohydrate of the formula (I) according to claim 1 , further comprising: after adding the hydrochloric acid and boric acid, heating the reaction mixture at reflux temperature.

5. The process for the preparation of Bis-(1(2)H-tetrazol-5-yl)-amine monohydrate of the formula (I) according to claim 4 , wherein the reaction mixture is heated at reflux temperature for 25 hours.

6. The process for the preparation of Bis-(1(2)H-tetrazol-5-yl)-amine monohydrate of the formula (I) according to claim 4 , further comprising:

after heating the reaction mixture at reflux temperature, cooling the reaction mixture to 55° C., and

adjusting the pH of the reaction mixture to less than 1.

7. The process for the preparation of Bis-(1(2)H-tetrazol-5-yl)-amine monohydrate of the formula (I) according to claim 6 , further comprising:

after adjusting the pH to less than 1, cooling the reaction mixture to a temperature of from 25° C. to 30° C., and

filtering the reaction mixture to obtain the Bis-(1(2)H-tetrazol-5-yl)-amine monohydrate of the formula (I).