Pyridinium tribromide

Synonym(s):Pyridinium bromide perbromide;Pyridine hydrobromide perbromide;Pyridine hydrobromide perbromide polymer-bound;Pyridine perbromide hydrobromide;Poly(4-vinylpyridine hydrobromide perbromide)

CAS NO.：39416-48-3
Empirical Formula: C5H6Br3N-2
Molecular Weight: 319.82
MDL number: MFCD00013223
EINECS: 254-446-8
SAFETY DATA SHEET (SDS)
Update Date: 2025-01-27 09:38:02

What is Pyridinium tribromide?

Chemical properties

red crystals

The Uses of Pyridinium tribromide

Pyridinium Tribromide is a reagent used in the α-thiocyanation of ketones and has also been applied to the synthesis of β-adrenergic blocking agents (also known as β-blockers) for patients with heart failure.

The Uses of Pyridinium tribromide

In small-scale brominations, where it is much more convenient and agreeable to measure and use than elemental bromine.

The Uses of Pyridinium tribromide

Pyridine hydrobromide perbromide is used as a brominating reagent in alfa-bromination and alfa-thiocyanation of ketones, phenols, unsaturated and aromatic ethers. It is used as a raw material in the preparation of beta-adrenergic blocking agents. Furthermore, it is used as an analytical reagent.

Purification Methods

It is a very good brominating agent-liberating one mol of Br2. Purify it by recrystallisation from glacial acetic acid (33g from 100mL of AcOH) to give orange-red crystals. [Fieser & Fieser Reagents for Organic Chemistry 1 967 1967, Englert & McElvain J Am Chem Soc 51 865 1929, Beilstein 20 II 103, 20/5 V 181.]

Properties of Pyridinium tribromide

Melting point:	127-133 °C
Density	2.9569 (rough estimate)
refractive index	1.6800 (estimate)
storage temp.	Store at <= 20°C.
solubility	soluble in Methanol
form	Powder, Crystals and/or Chunks
color	Red-orange to red to brown
Water Solubility	decomposes
Sensitive	Lachrymatory
Merck	14,7973
BRN	3690144
Stability:	Stable. Incompatible with strong oxidizing agents, strong bases.
CAS DataBase Reference	39416-48-3(CAS DataBase Reference)
EPA Substance Registry System	Pyridinium hydrogen tribromide (39416-48-3)

Safety information for Pyridinium tribromide

Signal word	Warning
Pictogram(s)	Exclamation Mark Irritant GHS07
GHS Hazard Statements	H315:Skin corrosion/irritation H335:Specific target organ toxicity, single exposure;Respiratory tract irritation
Precautionary Statement Codes	P261:Avoid breathing dust/fume/gas/mist/vapours/spray. P264:Wash hands thoroughly after handling. P264:Wash skin thouroughly after handling. P271:Use only outdoors or in a well-ventilated area. P280:Wear protective gloves/protective clothing/eye protection/face protection. P302+P352:IF ON SKIN: wash with plenty of soap and water.