Ethylenediamine Dihydroiodide (EDDI) CAS 5700-49-2
Ethylenediamine Dihydroiodide (EDDI): Properties and Applications
1. Introduction
Ethylenediamine dihydroiodide (EDDI) is a water-soluble salt formed by the reaction of ethylenediamine with hydroiodic acid (HI), where each ethylenediamine molecule is protonated by two molecules of hydroiodic acid. EDDI is widely used as an organic iodine source in animal nutrition and, less frequently, in certain technological and pharmaceutical processes. This article provides a comprehensive overview of its chemical profile, physicochemical properties, synthesis methods, applications, and safety considerations.
2. Nomenclature and Basic Information
Chemical name: Ethylenediamine dihydroiodide
Synonyms: EDDI, 1,2-ethanediamine dihydroiodide, ethane-1,2-diamine dihydroiodide, jodethamine, hydrodine
Molecular formula: C₂H₈N₂·2HI (C₂H₁₀I₂N₂)
Molecular weight: 315.92 g/mol
CAS number: 5700-49-2
MDL number: MFCD00035535
Iodine content: ~80% by weight
Appearance: White to off-white crystalline powder
3. Physicochemical Properties
Appearance: White to almost white powder or crystals
Solubility: Highly soluble in water
pH (100 g/L, H₂O, 20°C): 4.0–6.0
Melting point: Approximately 192°C
Stability: Stable under normal conditions; hygroscopic (absorbs moisture from air)
Storage: Store under inert gas, at or below 20°C, in tightly sealed containers
4. Synthesis
EDDI is typically produced by the direct neutralization of ethylenediamine with hydroiodic acid:
H₂N–CH₂–CH₂–NH₂ + 2 HI → [H₃N–CH₂–CH₂–NH₃]²⁺·2I⁻
The reaction is exothermic and is usually carried out under controlled cooling. The product is then crystallized and dried. Purification can be achieved through recrystallization from water or water-alcohol mixtures.
5. Applications
Animal nutrition (primary use): EDDI is widely used as an organic iodine supplement in animal feed, pet food, cattle feed, and salt blocks. It delivers superior bioavailability and stability compared to inorganic iodine sources. Iodine is essential for the synthesis of thyroid hormones (T3 and T4), which regulate metabolism and growth. The U.S. Food and Drug Administration (FDA) recognizes EDDI as generally recognized as safe (GRAS) as a nutrient source of iodine, with a recommended intake limit of 50 mg/head/day in cattle.
Foot rot prevention in cattle: EDDI has been shown to be effective in preventing foot rot in cattle. Studies have demonstrated a direct relationship between EDDI dosage levels and serum iodine concentrations, with a rate of 0.11 mg EDDI/kg/day correlating with serum iodine levels effective for foot rot prevention.
Poultry and swine nutrition: Research indicates that EDDI supplementation can improve growth performance, immune function, intestinal development, and intestinal barrier function in ducks. It has also been shown to mitigate immune and intestinal damage in ducks challenged with pathogenic E. coli.
Chemical synthesis: EDDI serves as a reagent in organic synthesis and as a source of iodine in certain chemical reactions. It is used in coordination chemistry, catalyst preparation, and the synthesis of specialty chemicals.
Veterinary medicine: EDDI is used therapeutically as an iodine source in veterinary applications.
6. Safety and Toxicology
Skin and eye irritation: EDDI may cause skin irritation (H315) and serious eye irritation (H319).
Ingestion: Harmful if swallowed (H302).
Iodism: Excessive intake can lead to iodism (iodine toxicity), characterized by irritation of mucous membranes, a metallic taste, and thyroid dysfunction.
Reactivity: Under certain conditions, EDDI can react with copper sulfate, zinc sulfate, and ferrous sulfate, forming metal iodides and releasing free iodine.
Storage: Store in a cool, dry, well-ventilated place, in tightly sealed containers, protected from moisture and light. Store under inert gas.
7. Regulatory Status
The FDA regulates EDDI as a feed additive with established limits for various animal species. In the European Union, EDDI is subject to regulations governing maximum permitted iodine concentrations in animal feed. Manufacturers must provide Safety Data Sheets (SDS) with handling, storage, and first-aid information.
8. Conclusion
Ethylenediamine dihydroiodide (EDDI, CAS 5700-49-2) is a highly soluble, organic iodine source with approximately 80% iodine by weight. Its primary application is in animal nutrition, where it prevents iodine deficiency, supports thyroid function, and helps prevent foot rot in cattle. EDDI also finds use in chemical synthesis and coordination chemistry. While generally recognized as safe when used at recommended levels, proper safety measures should be observed to avoid skin and eye irritation and to prevent excessive iodine intake. Ongoing research continues to explore its potential benefits in poultry and other livestock species.