Propionyl chloride
[CAS# 79-03-8]

Identification

• Classification: Pharmaceutical intermediate >> Heterocyclic compound intermediate >> Pyridine compound >> Fluoropyridine
• Name: Propionyl chloride
• Molecular Formula: C₃H₅ClO
• Molecular Weight: 92.52
• CAS Registry Number: 79-03-8
• EC Number: 201-170-0
• SMILES: CCC(=O)Cl

Properties

• Solubility: 1.182e+005 mg/L (25 °C water)
• Density: 1.1±0.1 g/cm³, Calc.^*
• Index of Refraction: 1.397, Calc.^*
• Melting point: -67.53 °C
• Boiling Point: 75.5±3.0 °C (760 mmHg), Calc.^*, 82.80 °C
• Flash Point: 11.7±0.0 °C, Calc.^*

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

Safety Data

• Hazard Symbols: GHS02;GHS06;GHS07 Danger
• Risk Statements: H225-H302-H314-H318-H331
• Safety Statements: P210-P233-P240-P241-P242-P243-P260-P261-P264-P264+P265-P270-P271-P280-P301+P317-P301+P330+P331-P302+P361+P354-P303+P361+P353-P304+P340-P305+P354+P338-P316-P317-P321-P330-P363-P370+P378-P403+P233-P403+P235-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Skin corrosion	Skin Corr.	1B	H314
Flammable liquids	Flam. Liq.	2	H225
Acute toxicity	Acute Tox.	4	H302
Acute toxicity	Acute Tox.	3	H331
Serious eye damage	Eye Dam.	1	H318

• Transport Information: UN 1815

Discovery and Applications

Propionyl chloride, an organic compound with the formula C3H5ClO, was first synthesized in the late 19th century during the expansion of organic chemistry as a field. This chemical, belonging to the acyl chloride family, was developed through the chlorination of propionic acid. The development of propionyl chloride provided chemists with a new reagent for introducing the propionyl functional group into organic molecules, facilitating a variety of synthetic pathways. Its reactive nature, due to the presence of the acyl chloride group, made it an essential tool in organic synthesis and industrial chemistry.

One of the primary uses of propionyl chloride is in the synthesis of esters and amides. When reacted with alcohols, it forms esters, and with amines, it produces amides. These reactions are fundamental in organic synthesis, enabling the creation of a variety of compounds used in pharmaceuticals, fragrances, and polymers.

Propionyl chloride is used as an intermediate in the synthesis of various pharmaceuticals. It plays a crucial role in constructing the molecular frameworks of many active pharmaceutical ingredients (APIs). For instance, it is involved in the synthesis of drugs like local anesthetics and certain anti-inflammatory agents. The ability to introduce the propionyl group efficiently helps streamline the drug development process.

In the agrochemical industry, propionyl chloride is employed in the synthesis of herbicides, insecticides, and fungicides. Its reactivity allows for the modification of chemical structures to enhance the efficacy and selectivity of agrochemical products, contributing to better pest and disease control in agriculture.

Propionyl chloride is used in the production of polymers and other materials. It can modify polymer backbones or introduce functional groups that enhance the properties of the final material. This application is vital in developing new materials with specific characteristics, such as improved strength, flexibility, or resistance to environmental factors.

As a versatile acylating agent, propionyl chloride is widely used in organic synthesis. It participates in Friedel-Crafts acylation reactions, introducing propionyl groups into aromatic compounds. This reaction is important for creating key intermediates in the synthesis of dyes, pigments, and other fine chemicals.

In research laboratories, propionyl chloride is frequently used for developing new chemical reactions and studying reaction mechanisms. Its ability to acylate a wide range of nucleophiles makes it a valuable reagent for exploring new synthetic methodologies and understanding chemical reactivity.

References

2024. Efficient and stable hole-transporting-layer-free perovskite solar cells by introducing propionyl chloride passivator. Applied Physics A, 129(6).
DOI: 10.1007/s00339-023-06749-0

2021. The Application of 1,2-Oxazinanes as Chiral Cyclic Weinreb Amide-Type Auxiliaries Leading to a Three-Component, One-Pot Reaction. Synthesis, 53(12).
DOI: 10.1055/a-1683-0484

2020. Tuning the size and hydrophobicity of nanohydrogels exploiting a self-assembly assisted polymerization mechanism for controlled drug delivery. Journal of Nanoparticle Research, 22(11).
DOI: 10.1007/s11051-020-05093-1