Benzimidazole is a sheet-like white crystal, with a temperature of 170 ℃, soluble in water and ethanol. 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.
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.
Benzimidazole is synthesized by cyclizing o-phenylenediamine with formic acid. A mixture of o-phenylenediamine and formic acid is heated in a water bath for 2 hours, then cooled. The pH is adjusted to 10 using 10% sodium hydroxide solution, followed by filtration of the precipitated solid. The solid is washed with cold water to obtain the crude product (yield: 90%). The crude product is then refluxed in water, decolorized with activated carbon, and hot-filtered. Upon cooling the filtrate to room temperature, the purified product is collected by filtration, washed with cold water, and dried at 100°C to obtain the final product.
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.
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.
ACUTE/CHRONIC HAZARDS: When heated to decomposition Benzimidazole emits highly toxic fumes.
Flash point data for Benzimidazole are not available. Benzimidazole is probably combustible.
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.
Poison by intravenous
and intraperitoneal routes. Moderately toxic
by ingestion. Mutation data reported. When
heated to decomposition it emits highly
toxic fumes of NOx.
It crystallises from water or aqueous EtOH (charcoal) and is dried at 100o for 12hours. [Beilstein 23 H 131, 23/6 V 196.]
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