2-Bromo-3'-chloropropiophenone
[CAS# 34911-51-8]

Identification

• Classification: Pharmaceutical intermediate >> Heterocyclic compound intermediate >> Pyrimidine compound >> Ketones
• Name: 2-Bromo-3'-chloropropiophenone
• Synonyms: 2-Bromo-1-(3-chlorophenyl)propan-1-one
• Molecular Formula: C₉H₈BrClO
• Molecular Weight: 247.52
• CAS Registry Number: 34911-51-8
• EC Number: 252-282-1
• SMILES: CC(C(=O)C1=CC(=CC=C1)Cl)Br

Properties

• Density: 1.5±0.1 g/cm³ Calc.^*, 1.532 g/mL (Expl.)
• Boiling point: 295.0±20.0 °C 760 mmHg (Calc.)^*
• Flash point: 132.2±21.8 °C (Calc.)^*
• Index of refraction: 1.57 (Calc.)^*

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

Safety Data

• Hazard Symbols: GHS07 Warning
• Risk Statements: H315-H317-H319-H335
• Safety Statements: P261-P264-P264+P265-P271-P272-P280-P302+P352-P304+P340-P305+P351+P338-P319-P321-P332+P317-P333+P317-P337+P317-P362+P364-P403+P233-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Eye irritation	Eye Irrit.	2	H319
Skin sensitization	Skin Sens.	1	H317
Skin irritation	Skin Irrit.	2	H315

Discovery and Applications

2-Bromo-3'-chloropropiophenone is an organic compound classified as a halogenated aryl ketone. Its structure features a phenyl ring substituted at the 3'-position with a chlorine atom and at the 1-position with a propiophenone moiety, in which the alpha carbon of the ketone is further substituted with a bromine atom. The IUPAC name of this compound is 1-(3-chlorophenyl)-2-bromo-1-propanone, and its molecular formula is C9H8BrClO.

This compound belongs to a class of alpha-haloketones that are known for their utility in organic synthesis, particularly as building blocks or intermediates in the preparation of heterocyclic compounds, pharmaceuticals, and agrochemicals. The presence of both bromine and chlorine atoms, along with the reactive ketone group, allows for selective functionalization via nucleophilic substitution or condensation reactions.

Synthesis of 2-bromo-3'-chloropropiophenone can typically be achieved by alpha-bromination of the corresponding 3'-chloropropiophenone using bromine (Br2) or N-bromosuccinimide (NBS) in the presence of acid or light to activate the reaction. The intermediate propiophenone is usually prepared by Friedel-Crafts acylation of 3-chlorobenzene with propionyl chloride in the presence of a Lewis acid catalyst such as AlCl3.

In synthetic applications, this compound can serve as an electrophile in the formation of α-substituted ketones, amines, and various heterocycles like oxazoles and thiazoles. It is reactive towards amines and thiols, allowing for straightforward formation of imines, amides, or thioethers.

Because of its alkylating potential, 2-bromo-3'-chloropropiophenone is handled with caution in laboratory settings. Like other α-haloketones, it can be irritating to the skin and mucous membranes and is considered potentially toxic. Proper personal protective equipment (PPE) and fume hood use are recommended during handling.

References

2008. Bupropion. Pharmaceutical Substances.
DOI: Not available