What Is Isophorone?
Isophorone is an organic compound with the chemical formula C9H14O and a cyclic ketone structure.
It is found naturally in cranberries, and its CAS number is 78-59-1. It has a molecular weight of 138.21, a melting point of -8.1°C, and a boiling point of 215.2°C. It is a clear colorless pale yellow liquid at room temperature.
The odor is described as peculiar. The density is 0.92 g/mL. It is extremely soluble in ethanol, acetone, and ether, and virtually insoluble in water.
Uses of Isophorone
The main uses of isophorone are in solvents, paints, and raw materials for agrochemicals. Solvents include adhesives, copolymers, coatings, finishes, and insecticides, while paints include inks, paints, and lacquers.
Other applications include synthetic intermediates, preservatives for wood products, and waterproofing agents for floors. In agriculture, isophorone is used as a solvent for acid amide herbicides. The use of isophorone as a solvent is said to have been discovered in the process of finding a way to treat acetone, a byproduct of the production of phenol by the cumene process.
Isophorone is a synthetic intermediate of isophorone diisocyanate (C12H18N2O2, CAS No.: 4098-71-9), which is known as a raw material for polyurethane resin coatings in the paint field, and isophoronediamine (C10H22N2, CAS No.: 2855-13-2), which is known as a raw material for epoxy resin curing agents in adhesives, CAS No.: 2855-13-2), which is known as a raw material for epoxy resin curing agents in adhesive applications.
Properties of Isophorone
Isophorone is a flammable liquid with a flash point of 90°C and a spontaneous combustion point of 462°C. It is stable under normal handling. Although isophorone is considered stable under normal handling, combustion in the event of a fire will produce toxic gases such as carbon monoxide and carbon dioxide.
Since it reacts with strong oxidizers, oxidizing agents, and strong bases, mixing with these substances should be avoided in storage. Note that isophorone dimerizes by undergoing a [2+2] photocycloaddition reaction when exposed to sunlight in aqueous solution.
Types of Isophorone
Isophorone is sold primarily as a reagent product for research and development and as an organic solvent for industrial use. Reagent products are available in a variety of volumes, such as 5mL, 25mL, 100mL, 500mL, and 1L, and are offered in volumes that are easy to handle in the laboratory. These reagent products can be stored at room temperature.
As an industrial solvent, it is sold in large packages to factories. Packages include 1L cans, 4L cans, 18L cans, drums, containers, and tank trucks.
Other Information on Isophorone
1. Synthesis of Isophorone
Isophorone is synthesized by the self-condensation of three molecules of acetone. The specific synthetic flow is as follows.
- Two molecules of acetone dehydrate after aldol condensation to form mesityl oxide.
- Another molecule of acetone enolates and then undergoes Michael addition to this intermediate.
- Cyclization and dehydration produce isophorone.
The respective yields of mesityl oxide and isophorone depend on the reaction conditions.
2. Regulatory Information on Isophorone
Isophorone is a flammable liquid, as mentioned above, and is therefore a compound designated as a “Hazardous Substance, Class IV, Petroleum No. 3, Hazardous Rank III” under the Fire Service Law.
It is also designated as a “Hazardous and Noxious Substance to be Notified by Name” and “Hazardous and Noxious Substance to be Labeled by Name” under the Industrial Safety and Health Law, and as a “Priority Assessment Chemical Substance” under the Law Concerning the Evaluation of Chemical Substances and Regulation of Their Manufacture, etc., and is also designated under the Marine Pollution Control Law.