2-Isopropylthioxanthone
[CAS 5495-84-1]

Identification

• Classification: Analytical chemistry >> Standard >> Volatile organic compounds (VOCs)
• Name: 2-Isopropylthioxanthone
• Synonyms: 2-Isopropyl-9H-thioxanthen-9-one
• Molecular Formula: C₁₆H₁₄OS
• Molecular Weight: 254.35
• CAS Registry Number: 5495-84-1
• EC Number: 226-827-9
• SMILES: CC(C)C1=CC2=C(C=C1)SC3=CC=CC=C3C2=O

Properties

• Solubility: 0.03224 mg/L (25 °C water)
• Density: 1.2±0.1 g/cm³, Calc.^*
• Index of Refraction: 1.638, Calc.^*
• Melting point: 141.67 °C
• Boiling Point: 398.9±32.0 °C (760 mmHg), Calc.^*, 379.06 °C
• Flash Point: 217.0±10.8 °C, Calc.^*

^* Calculated using Advanced Chemistry Development (ACD/Labs) Software.

Safety Data

• Hazard Symbols: GHS07;GHS08;GHS09 Warning
• Risk Statements: H302-H361f-H373-H400-H410-H413
• Safety Statements: P203-P260-P264-P270-P273-P280-P301+P317-P318-P319-P330-P391-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Chronic hazardous to the aquatic environment	Aquatic Chronic	4	H413
Acute toxicity	Acute Tox.	4	H302
Chronic hazardous to the aquatic environment	Aquatic Chronic	1	H410
Acute hazardous to the aquatic environment	Aquatic Acute	1	H400
Reproductive toxicity	Repr.	2	H361
Specific target organ toxicity - repeated exposure	STOT RE	2	H373
Reproductive toxicity	Repr.	2	H361f
Skin sensitization	Skin Sens.	1	H317

Discovery and Applications

2-Isopropylthioxanthone is a notable chemical compound primarily utilized in the field of photochemistry. This substance, classified as a thioxanthone derivative, was first synthesized and reported in the mid-20th century, with its discovery significantly contributing to advancements in ultraviolet (UV) and visible light photoinitiation processes. The chemical structure of 2-isopropylthioxanthone consists of a thioxanthone core with an isopropyl group attached to the 2-position of the aromatic ring.

The discovery of 2-isopropylthioxanthone is attributed to its innovative use in photoinitiators for polymerization reactions. As a photoinitiator, it plays a critical role in initiating polymerization when exposed to UV light. This property is highly valuable in various industrial applications, particularly in the production of coatings, adhesives, and inks where rapid curing and hardening are essential.

In the field of coatings, 2-isopropylthioxanthone is employed to enhance the efficiency and speed of the curing process. It helps in achieving a high degree of cross-linking and improving the overall mechanical properties of the coating. This is particularly beneficial in applications requiring durable and resistant coatings for metal, wood, and plastic surfaces.

Another significant application of 2-isopropylthioxanthone is in the formulation of inks. In the printing industry, it is used as a photoinitiator to ensure fast curing of UV-curable inks, which is crucial for high-speed printing processes. The rapid curing achieved with 2-isopropylthioxanthone enhances print quality and durability, making it a preferred choice for various printing applications.

Moreover, 2-isopropylthioxanthone is also utilized in the synthesis of advanced polymer materials. Its ability to initiate polymerization under UV light makes it suitable for producing specialty polymers with specific properties required for high-performance applications.

Overall, the discovery and application of 2-isopropylthioxanthone have had a profound impact on industries that rely on UV curing processes. Its role as a photoinitiator in coatings, inks, and polymer synthesis demonstrates its significance in modern manufacturing and material science.

References

2024. Hydrogen self-supplying initiators excited by visible light for the fabrication of transparent films. Science China Chemistry, 67(10).
DOI: 10.1007/s11426-024-2118-0

2020. The hydrogen transfer reaction between the substance of triplet state thioxanthone and alkane with sp3 hybridization hydrogen. Journal of Molecular Modeling, 26(2).
DOI: 10.1007/s00894-020-4300-4

2016. In silico prediction and in vivo analysis of antiestrogenic potential of 2-isopropylthioxanthone (2-ITX) in juvenile goldfish (Carassius auratus). Ecotoxicology and Environmental Safety, 133(1).
DOI: 10.1016/j.ecoenv.2016.07.021