5-Chlorothiophene-2-carbonyl chloride
[CAS# 42518-98-9]

Identification

• Classification: Pharmaceutical intermediate >> Heterocyclic compound intermediate >> Thiophene compound
• Name: 5-Chlorothiophene-2-carbonyl chloride
• Molecular Formula: C₅H₂Cl₂OS
• Molecular Weight: 181.04
• CAS Registry Number: 42518-98-9
• EC Number: 800-982-8
• SMILES: C1=C(SC(=C1)Cl)C(=O)Cl

Properties

• Melting point: 4 °C

Safety Data

• Hazard Symbols: GHS05 Danger
• Risk Statements: H290-H314-H318
• Safety Statements: P234-P260-P264-P264+P265-P280-P301+P330+P331-P302+P361+P354-P304+P340-P305+P354+P338-P316-P317-P321-P363-P390-P405-P406-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Serious eye damage	Eye Dam.	1	H318
Skin corrosion	Skin Corr.	1B	H314
Skin corrosion	Skin Corr.	1	H314
Substances or mixtures corrosive to metals	Met. Corr.	1	H290
Skin corrosion	Skin Corr.	1C	H314

Discovery and Applications

5-Chlorothiophene-2-carbonyl chloride, with the molecular formula C6H3ClOClS, is a chemical compound notable for its utility in organic synthesis and material science. This compound features a thiophene ring substituted with a chlorine atom at the 5-position and a carbonyl chloride group at the 2-position, providing a unique structure that enables various chemical transformations.

The synthesis of 5-chlorothiophene-2-carbonyl chloride typically begins with the chlorination of 5-chlorothiophene, followed by the introduction of the carbonyl chloride group. The chlorination is usually performed using a chlorinating agent such as chlorine gas or a chlorinating reagent like thionyl chloride in the presence of a solvent. The resulting chlorinated thiophene is then subjected to a reaction with phosgene or oxalyl chloride to convert the hydroxyl group into a carbonyl chloride. This process yields 5-chlorothiophene-2-carbonyl chloride, a compound with a reactive carbonyl chloride group.

In organic synthesis, 5-chlorothiophene-2-carbonyl chloride serves as a versatile intermediate. The carbonyl chloride group is highly reactive, allowing for the introduction of various functional groups through nucleophilic substitution reactions. This reactivity makes the compound an essential building block for creating complex organic molecules. It is particularly useful in the synthesis of pharmaceuticals, agrochemicals, and other fine chemicals, where precise modifications of the thiophene ring are required.

One significant application of 5-chlorothiophene-2-carbonyl chloride is in the pharmaceutical industry. The compound is employed to synthesize various biologically active molecules, including those with potential therapeutic properties. For instance, the carbonyl chloride group facilitates the formation of amides, esters, and other derivatives, which can be further modified to develop new drug candidates. The ability to selectively functionalize the thiophene ring makes this compound valuable in designing and optimizing pharmaceuticals with targeted activity.

Additionally, 5-chlorothiophene-2-carbonyl chloride finds applications in the field of material science. It is used as a precursor for the synthesis of functionalized thiophene-based materials. These materials are of interest in the development of electronic devices, sensors, and organic semiconductors due to their unique electronic and optical properties. The ability to tailor the electronic characteristics of the thiophene ring by introducing different substituents through reactions with carbonyl chloride enhances the performance and utility of these materials.

The compound's role in both pharmaceuticals and material science underscores its importance as a reactive intermediate in chemical synthesis. The continued research into the applications of 5-chlorothiophene-2-carbonyl chloride reveals its potential in developing new materials and drugs, highlighting its versatility and significance in various scientific fields.

Overall, 5-chlorothiophene-2-carbonyl chloride is a key compound in organic synthesis, offering valuable reactivity for the preparation of complex molecules and functional materials. Its applications in pharmaceuticals and material science illustrate its importance in advancing both drug development and technological innovations.

References

1999. Synthesis of Substituted Alkoxythiophenes: Thiophene Analogues of Dazoxiben. Monatshefte für Chemie / Chemical Monthly, 130(5).
DOI: 10.1007/pl00010245

2015. Facile approach for the synthesis of rivaroxaban using alternate synthon. Sustainable Chemical Processes, 3(1).
DOI: 10.1186/s40508-015-0036-3

2016. Comparison of the Hydrolysis and Esterification Methods for the Determination of Genotoxic 5-Chlorothiophene-2-Carbonyl Chloride in Rivaroxaban Using HPLC. Chromatographia, 79(5-6).
DOI: 10.1007/s10337-016-3038-8