Chemical Properties
colourless crystals or faintly yellow powder
Uses
3,5-Diamino-1,2,4-triazole is used as an inhibitor of DNA synthesis. It also serves as an antitumor agents in the treatment of epigenetically-based diseases. It acts as a corrosion inhibitor for copper.
Definition
ChEBI: An aromatic amine that is 1,2,4-triazole substituted at positions 3 and 5 by amino groups.
General Description
Colorless crystals.
Air & Water Reactions
1H-1,2,4-Triazole-3,5-diamine is sensitive to air. Dust can be explosive when suspended in air at specific concentrations. Water soluble.
Reactivity Profile
The triazoles, of which 1H-1,2,4-Triazole-3,5-diamine is a member, are a group of highly explosive materials that are sensitive to heat, friction, and impact. Sensitivity varies with the type of substitution to the triazole ring. The amine substituted derivatives, 1H-1,2,4-Triazole-3,5-diamine, tend not to be explosion sensitive. Metal chelated and halogen substitution of the triazol ring make for a particularly heat sensitive material. Azido and nitro derivatives have been employed as high explosives. No matter the derivative these materials should be treated as explosives. 1H-1,2,4-Triazole-3,5-diamine forms salts readily with acids.
Health Hazard
SYMPTOMS: 1H-1,2,4-Triazole-3,5-diamine is stable under normal laboratory conditions.
Fire Hazard
Flash point data for 1H-1,2,4-Triazole-3,5-diamine are not available. 1H-1,2,4-Triazole-3,5-diamine is probably combustible.
Safety Profile
Human systemic effects
by intravenous route: leukopenia (reduced white blood cell count) and thrombo
cytopenia (reduced blood platelet count).
Human mutation data reported.
Questionable carcinogen with experimental
tumorigenic data. When heated to
decomposition it emits toxic fumes of NOx.
Synthesis
1. 500 mL of water was added to a 2000 mL three-necked flask and 200.0 g of dicyandiamide was added with vigorous stirring for 20 minutes to form a turbid liquid.
2. 155 g of hydrazine sulfate was added to the cloudy liquid and the mixture was heated to 50°C. 3. 72 mL of 80% water was added slowly.
3. 72 mL of 80% hydrazine hydrate was added slowly, followed by warming the reaction system to 120°C to 125°C, during which all solids gradually dissolved.
4. the reaction mixture was stirred continuously at 120°C to 125°C for 16 hours, during which time a small amount of solids precipitated out of solution.
5. Upon completion of the reaction, the heating was stopped and the reaction mixture was cooled to room temperature.
6. The pH of the reaction mixture was adjusted to 9 by adding 100 mL of 10% sodium carbonate solution.
7. The reaction mixture was transferred to a 2 L dispensing funnel and the organic phase was extracted with 500 mL of dichloromethane.
8. The organic phase was washed with water and dried with anhydrous sodium sulfate.
9. Dichloromethane was removed by evaporation to give a white solid product.
10. The white solid was dried in a hot air oven to give a final product of 169 g of 3,5-diamino-1,2,4-triazole in 72% yield based on dicyandiamide.
Purification Methods
The triazole crystallises from water or EtOH. [Beilstein 26 III/IV 1161.]
References
[1] Patent: CN105968058, 2016, A. Location in patent: Paragraph 0073; 0074; 0075
[2] Chemische Berichte, 1912, vol. 45, p. 2733
[3] Journal fuer Praktische Chemie (Leipzig), 1913, vol. <2>88, p. 312
[4] Gazzetta Chimica Italiana, 1894, vol. 24, p. I 491
[5] Chemistry - A European Journal, 2010, vol. 16, # 5, p. 1572 - 1584
