Alkali Salts of 5‐Aminotetrazole – Structures and Properties

Alkali salts of 5‐aminotetrazole (5‐At) are common intermediates in synthesis of alkylated aminotetrazoles and their derivatives and can also be used as coloring agents in modern pyrotechnics, due to their high nitrogen content. The crystal structures of A+ 5‐At– * × H2O (A = Li+ (6), Na+ x = 3 (7), K+ (8), Rb+ (9) and Cs+ (10)) were determined using single crystal X‐ray diffraction and a detailed description is given in this work. In addition the compounds were characterized using vibrational (IR and Raman) and NMR spectroscopy, elemental analysis and differential scanning calorimetry (DSC). Since tetrazoles are known to be promising energetic materials the heats of formation were calculated using bomb calorimetric measurements and the sensitivities of all compounds were tested using BAM methods. They show no sensitivity towards friction (< 360 N) or impact (< 50 J). X‐ray determinations: 6: monoclinic, P21/c, a = 4.7900(5) Å, b = 10.6139(11) Å, c = 7.0369(8) Å, β = 103.260(9)°, V = 348.22(7) Å3, Z = 4; 7: triclinic, P 1 , a = 5.8689(7) Å, b = 10.0258(9) Å, c = 12.1710(12) Å, α = 87.335(11)°, β = 77.546(9)°, γ = 80.059(9)°, V = 688.76(13) Å3, Z = 4; 8: monoclinic, P21/c, a = 9.8516(9) Å, b = 6.8702(8) Å, c = 6.8372(7) Å, β = 115.613(11)°, V = 417.29(8) Å3, Z = 4; 9: orthorhombic, Pnma, a = 7.4221(9) Å, b = 6.8053(8) Å, c = 9.0133(9) Å, V = 455.26(9) Å3, Z = 4; 10: orthorhombic, Pnma, a = 8.0538(7) Å, b = 6.9305(6) Å, c = 9.1021(8) Å, V = 508.05Å3, Z = 4.