Benzimidazole Property

Melting point:

169-171 °C (lit.)

Boiling point:

360 °C

Density 

1.1151 (rough estimate)

refractive index 

1.5500 (estimate)

Flash point:

360°C

storage temp. 

Store below +30°C.

solubility 

xylene: soluble1g in 2g (boiling)(lit.)

form 

Crystalline Powder or Crystals

pka

5.532(at 25℃)

color 

Beige to brown

Water Solubility 

sparingly soluble

λmax

271nm(MeOH)(lit.)

Merck 

14,1081

BRN 

109682

Stability:

Stable. Combustible. Incompatible with strong oxidising agents.

InChIKey

HYZJCKYKOHLVJF-UHFFFAOYSA-N

LogP

1.320

CAS DataBase Reference

51-17-2(CAS DataBase Reference)

NIST Chemistry Reference

1H-Benzimidazole(51-17-2)

EPA Substance Registry System

Benzimidazole (51-17-2)

Safety

Hazard Codes 

Xi

Risk Statements 

36/37/38

Safety Statements 

37/39-26-24/25

WGK Germany 

3

RTECS 

DD5425000

Hazard Note 

Irritant

TSCA 

Yes

HS Code 

29339990

Hazardous Substances Data

51-17-2(Hazardous Substances Data)

Toxicity

LD50 oral in mouse: 2910mg/kg

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Warning

Hazard statements

H302Harmful if swallowed

Precautionary statements

P264Wash hands thoroughly after handling.

P264Wash skin thouroughly after handling.

P270Do not eat, drink or smoke when using this product.

P301+P312IF SWALLOWED: call a POISON CENTER or doctor/physician IF you feel unwell.

P501Dispose of contents/container to..…

Benzimidazole Chemical Properties,Usage,Production

Chemical Properties

white crystals

Uses

Usually used as template compound in the preparation of molecularly imprinted polymer via electropolymerization and electrodeposition of pyrrole on a pencil graphite electrode,and also used in the preparation of benzimidazolium surfactant, 1-hexadecyl-1H-benzimidazole.

Uses

Benzimidazole is a building block for making anthelmintic drugs like albendazole, mebendazole and triclabendazole and anti-ulcer drugs like pantoprazole, rabeprazole, lansoprazole and omeprazole. It is used in the preparation of pyrene derived benzimidazole linked polymers (BILPs), which are used for selective carbon dioxide separation applications due to their properties like porous materials, regenerability and sorbent selection parameters.

Definition

ChEBI: 1H-benzimidazole is the 1H-tautomer of benzimidazole. It is a benzimidazole and a polycyclic heteroarene. It is a conjugate acid of a benzimidazolide. It is a tautomer of a 4H-benzimidazole, a 2H-benzimidazole and a 3aH-benzimidazole.

General Description

White tabular crystals.

Air & Water Reactions

Insoluble in water.

Reactivity Profile

An amine. Neutralizes acids to form salts plus water. These acid-base reactions are exothermic. May be incompatible with isocyanates, halogenated organics, peroxides, phenols (acidic), epoxides, anhydrides, and acid halides. Flammable gaseous hydrogen is generated in combination with strong reducing agents, such as hydrides. May be shock sensitive.

Health Hazard

ACUTE/CHRONIC HAZARDS: When heated to decomposition Benzimidazole emits highly toxic fumes.

Fire Hazard

Flash point data for Benzimidazole are not available. Benzimidazole is probably combustible.

Pharmacology

The mode of action of benzimidazoles has been described in several comprehensive reviews (1,32,33). The primary mode of action of benzimidazoles has been identified as the specific binding to the β-subunit of fungal tubulin and, consequently, an interference with microtubule assembly. Microtubules are major components of the fungal cytoskeleton and are involved in meiosis and mitosis, both of which are blocked in the presence of benzimidazoles.

Safety Profile

Poison by intravenous and intraperitoneal routes. Moderately toxic by ingestion. Mutation data reported. When heated to decomposition it emits highly toxic fumes of NOx.

Purification Methods

It crystallises from water or aqueous EtOH (charcoal) and is dried at 100o for 12hours. [Beilstein 23 H 131, 23/6 V 196.]