Synthesis of tetrazolate salts

A method of synthesis of copper (I) 5-nitrotetrazolate, the method comprises:

• a) using a salt of 5-aminotetrazole as a starting compound for the synthesis of the copper (I) 5-nitrotetrazolate;
• b) adding an acid to an aqueous mixture comprising of (i) the salt of 5-aminotetrazole, (ii) sodium nitrite (NaNO2) and (iii) a copper salt or its hydrated form, at a suitable temperature to form a reaction mixture;
• c) stirring and heating the reaction mixture to form 5-nitrotetrazole in situ;
• d) adding an aqueous solution of sodium hydroxide (NaOH) to the reaction mixture at a particular temperature to convert 5-nitrotetrazole formed in step (c) to its sodium salt in situ, and a precipitated dark compound;
• e) filtering off the precipitated dark compound formed in step (d) to obtain a filtrate containing the said sodium salt of 5-nitrotetrazole;
• f) heating the filtrate containing the sodium salt of 5-nitrotetrazole to a particular temperature followed by addition of cuprous chloride (CuCl) to the filtrate until a colored solid is precipitated out of the reaction mixture;
• g) filtering the precipitated colored solid after removing all impurities, washing the precipitated solid successively with hot water and alcohol, and drying the precipitated colored solid to obtain the copper (I) 5-nitrotetrazolate.