99% Cuprous iodide CAS 7681-65-4

What is cuprous iodide? What are its industrial applications?

1. What is Cuprous iodide?

Cuprous iodide, also known as copper monoiodide, copper iodide (I), or Copper(I) iodide, CuI, is an inorganic compound composed of monovalent copper ions and iodide ions. It is one of the most important copper catalysts in organic synthesis. Its chemical formula is usually written as:

CuI (CAS No.: 7681-65-4, EINECS No.: 231-674-6, molecular weight approximately 190.45)

It is a white to grayish-white powder at room temperature, which decomposes easily in light and turns brown (photosensitive). It is insoluble in water but soluble in ammonia, potassium iodide solution, and concentrated hydrochloric acid. Its relative density is about 5.62, and its melting point is about 605℃. Industrially, it is prepared by the direct combination of copper and iodine, the reaction of iodide ions with cuprous chloride, or by the reduction of copper sulfate with iodides.

Structurally, the monovalent copper ion (Cu+) in cuprous iodide has unique coordination chemistry properties, and can form complexes with a variety of ligands (such as 1,10-phenanthroline and diamines). It can serve as a catalyst core for organic coupling reactions and also has p-type semiconductor characteristics, making it a dual-identity material of "catalyst + semiconductor".

Chemically, cuprous iodide is stable and insoluble in water, but it may slowly oxidize and discolor upon exposure to light or prolonged exposure to air. It has low solubility in organic solvents and is often used in powder form or dissolved in reaction systems in combination with ligands. It should be stored in a sealed, light-proof, and moisture-proof container.

Industrial-grade cuprous iodide refers to products used in organic synthesis catalysis, feed additives, and analytical applications, typically with a purity of 98% or higher (e.g., 98%, 99%, 99.5%).In the case of industrial-grade products, the following indicators are more emphasized:

1. Content (purity)

Feed addition content determines catalytic activity and precision. Industrial grade is usually above 98% and catalytic grade needs above 99%, which is the core index of product specifications.

Iron content

The metallic impurities such as iron can affect the catalytic performance, color and application effects, which should be controlled in a reasonable range.

Moisture

Moisture content affects product storage stability and the reaction system, and must be strictly controlled.

Water-insoluble and acid-insoluble substances

Insoluble matter reflects the total amount of impurities and is crucial for high-purity catalytic applications; it must be controlled within an extremely low range.

Appearance and color

The product must be a white to off-white powder. The color reflects the purity and batch stability, and the degree of color change upon exposure to light is a quality reference.

6. granularity

Dissolution rate and catalytic dispersibility are affected by particle size. Different applications require different particle sizes and batch consistency has to be maintained.

II. What are the applications of industrial-grade cuprous iodide?

Due to its unique properties of “monovalent copper coordination chemistry + semiconductor characteristics”, industrial-grade cuprous iodide has extremely wide applications in organic synthesis as well as nutrition and materials.

1. Coupling catalyst for organic production (core industrial application)

Cuprous iodide is a key copper catalyst for classical coupling reactions such as Ullmann, Sonogashira, and Stille couplings. Its catalytic performance can be greatly improved when combined with ligands such as 1,10-phenanthroline. It is widely utilized in the construction of CC, CN and CO bonds and is the core catalyst for fine chemical synthesis.

2. N-arylation catalysts for amines (commercial grade)

Cuprous iodide is an effective catalyst for the N-arylation of amines and amino acids to construct aromatic amine structural units, which is widely used in the synthesis of dyes and functional materials.

3. Click on the chemical catalyst (CuAAC, industrial grade)

Cuprous iodide is a classical copper catalyst for azide-alkyne cycloaddition (click chemistry) to efficiently construct 1,2,3-triazole structures, and is widely used in bioconjugation and polymer materials.

4. Industrial grade semiconductor and optoelectronic materials

Cuprous iodide is a p-type transparent conductive semiconductor material for the research and fabrication of solar cells, photodetectors, light-emitting devices and transparent electronic devices. And it is a hot material in the new field of optoelectronic materials.

5. Polymer Heat Stabilizer (Grade: industrial)

Cuprous iodide is used as a heat stabilizer and antioxidant for engineering plastics and special synthetic rubbers to delay high-temperature aging and degradation of polymeric materials.

6. Industrial grade raw materials for marine antifouling coatings

Cuprous iodide can be used to prepare copper based antibacterial complexes. The copper based antibacterial complexes can be used as raw materials for antifouling agents against marine organisms and can be used in marine antifouling coating systems.

7. Dehalogenation reagent of organic halide (industrial grade)

Cuprous iodide is useful in the reduction of halogenated organic compounds, dehalogenation, purification of fine intermediates and treatment of organic pollutants.

8. Materials of electronic grade solid-state lithium battery electrolyte precursors

Cuprous iodide is used in the preparation of copper-iodine based solid ionic conductors, serving as a precursor in the synthesis of solid electrolytes for solid state lithium batteries.

9. Composite ice core additive for artificial weather modification (industrial grade)

Cuprous iodide can be used as a composite ice-forming aid, combined with silver iodide to prepare composite artificial rainmaking agents, which helps to improve the efficiency of ice nucleus formation. It is mostly used in formulation research experiments and is not used as an independent artificial rainmaking agent.

10. Other industrial applications

It can be used as anode ray tube covering material and resin modifier; with the development of catalytic chemistry and optoelectronic materials, the application scope of industrial-grade cuprous iodide continues to expand.

It should be noted that industrial-grade specifications do not equate to "risk-free": Cuprous iodide contains copper, and long-term excessive intake of copper is harmful to health. Its use in feed and nutrition must strictly comply with regulatory limits. During handling, dust inhalation and skin contact should be avoided. It is prone to discoloration when exposed to light and must be stored away from light. Industrial-grade products are strictly prohibited from consumption, and copper-containing waste liquids must be disposed of in compliance with regulations.

Summarize

Cuprous iodide (CuI, CAS No. 7681-65-4, EINECS No. 231-674-6) is a white to off-white powder, insoluble in water and easily decomposes and changes color upon exposure to light. Due to the unique coordination chemistry and p-type semiconductor properties of monovalent copper, it has become an important chemical in organic synthesis, nutrition, and materials science. In daily life, we encounter it through iodized salt, animal products, pesticides, and optoelectronic products. Industrially, cuprous iodide is widely used in organic synthesis coupling catalysts (Ullmann, Sonogashira, Stille coupling and click chemistry), amine N-arylation catalysts, iodine sources in iodized salt, animal feed additives, semiconductor optoelectronic materials, and analytical reagents. It is a versatile copper compound that bridges the gap between "monovalent copper chemistry" and "nutritional fortification and optoelectronic materials."