Ethanethiol
[CAS# 75-08-1]

Identification

• Classification: Organic raw materials >> Organic sulfur compound
• Name: Ethanethiol
• Synonyms: Ethyl mercaptan
• Molecular Formula: C₂H₆S
• Molecular Weight: 62.13
• CAS Registry Number: 75-08-1
• EC Number: 200-837-3
• SMILES: CCS

Properties

• Solubility: 0.60-0.80 g/100g
• Density: 0.839
• Melting point: -148 °C
• Boiling point: 35 °C
• Refractive index: 1.4296-1.4316
• Flash point: -45 °C

Safety Data

• Hazard Symbols: GHS02;GHS07;GHS09 Danger
• Risk Statements: H225-H332-H400-H410
• Safety Statements: P210-P233-P240-P241-P242-P243-P261-P264-P270-P271-P273-P280-P301+P317-P303+P361+P353-P304+P340-P317-P330-P370+P378-P391-P403+P235-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Chronic hazardous to the aquatic environment	Aquatic Chronic	1	H410
Acute hazardous to the aquatic environment	Aquatic Acute	1	H400
Acute toxicity	Acute Tox.	4	H332
Flammable liquids	Flam. Liq.	2	H225
Acute toxicity	Acute Tox.	4	H302
Skin sensitization	Skin Sens.	1B	H317
Flammable liquids	Flam. Liq.	1	H224
Eye irritation	Eye Irrit.	2	H319
Skin sensitization	Skin Sens.	1	H317
Specific target organ toxicity - single exposure	STOT SE	3	H336
Specific target organ toxicity - single exposure	STOT SE	3	H335
Specific target organ toxicity - single exposure	STOT SE	1	H370

• Transport Information: UN 2363

Discovery and Applications

Ethanethiol, also known as ethyl mercaptan, is a simple organosulfur compound with the chemical formula C2H5SH. This compound features a sulfur atom bonded to an ethyl group and a hydrogen atom, making it one of the simplest thiols. Its discovery and applications highlight its importance in various chemical and industrial processes.

The discovery of ethanethiol dates back to the early 19th century. The compound was first synthesized by the French chemist Auguste Cahours in 1860. Cahours and his contemporaries were exploring the chemistry of sulfur compounds, and ethanethiol was identified as a distinct member of the thiol family due to its characteristic odor and chemical properties. Its discovery opened new avenues in the study of sulfur-containing organic compounds and their reactivity.

In the chemical industry, ethanethiol is primarily used as a chemical intermediate and in the synthesis of various other compounds. Its reactivity as a thiol makes it valuable for introducing sulfur into organic molecules. One of its notable applications is in the production of thiol-based reagents, which are used in a wide range of chemical reactions. For example, ethanethiol is employed in the synthesis of thiol-containing pharmaceuticals and agrochemicals. Its ability to form disulfide bonds with other thiol groups is exploited in the creation of cross-linked polymers and in protein chemistry.

Ethanethiol also plays a crucial role in the oil and gas industry. It is used as a natural gas odorant due to its strong, distinctive smell, which serves as a safety measure to detect gas leaks. Natural gas, primarily methane, is odorless in its natural state, and the addition of ethanethiol helps to ensure that leaks are easily detectable, thus preventing potential hazards and improving safety in residential and commercial settings.

In the field of environmental science, ethanethiol has been studied for its role in the atmospheric chemistry of sulfur compounds. Its presence in the atmosphere can contribute to the formation of sulfur-containing pollutants, which have implications for air quality and environmental health. Researchers monitor and analyze ethanethiol levels to understand its impact on atmospheric processes and its contribution to sulfur pollution.

Additionally, ethanethiol is used in laboratory settings as a reagent in various chemical analyses. Its ability to react with other chemicals and form specific derivatives makes it a useful tool in analytical chemistry, particularly in the identification and quantification of sulfur-containing compounds.

Overall, ethanethiol is a versatile compound with a range of applications spanning industrial, environmental, and chemical research fields. Its discovery has contributed to advancements in sulfur chemistry and its practical uses have enhanced safety measures and industrial processes.

References

2001. Development of a New Methanethiol Quantification Method Using Ethanethiol as an Internal Standard. Journal of Agricultural and Food Chemistry, 49(7).
DOI: 10.1021/jf001447u

2009. Analysis of Phosphorylated Peptides by Double Pseudoneutral Loss Extraction Coupled with Derivatization Using N-(4-Bromobenzoyl)aminoethanethiol. Analytical Chemistry, 81(20).
DOI: 10.1021/ac9017988