Benzocaine

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Benzocaine
220px-Benzocaine.svg.png
Names
IUPAC name
Ethyl 4-aminobenzoate
Systematic IUPAC name
Ethyl 4-aminobenzoate
Other names
Anbesol
Orajel
Cepacol
Identifiers
Jmol-3D images Image
Properties
C9H11NO2
Molar mass 165.189 g/mol
Appearance White solid
Density 1.17g/cm3
Melting point 89 °C (192 °F; 362 K)
Boiling point 310 °C (590 °F; 583 K)
Slightly soluble
Solubility Very soluble in chloroform, ethanol, ethyl ether;
Soluble in diluted acids
Hazards
Safety data sheet ScienceLab
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Benzocaine is a topical anesthetic that helps to numb the pain and itching. It's used as a topical pain reliever or in cough drops. Benzocaine combined with antipyrine forms A/B otic drops to relieve ear pain and remove earwax.

Properties

Chemical

Benzocaine is the ethyl ester of p-aminobenzoic acid (PABA). It can be prepared from PABA and ethanol by Fischer esterification or via the reduction of ethyl p-nitrobenzoate.

Physical

Benzocaine is sparingly soluble in water; it is more soluble in dilute acids and very soluble in ethanol, chloroform and ethyl ether.

Availability

Benzocaine is sold in various drugstores.

Preparation

Benzocaine can be prepared by esterfication using 4-aminobenzoic acid and ethanol. It can also be prepared by reduction of ethyl 4-nitrobenzoate to the amine.

In industrial practice, the reducing agent is usually iron and water in the presence of a little acid.

Projects

  • Local anesthetic

Handling

Safety

Do not use benzocaine topical if you have ever had methemoglobinemia in the past.

Storage

Benzocaine should be stored in closed bottles, away from moisture and air, if stored for long periods of time.

Disposal

Benzocaine can be either oxidized with Fenton's reagent or poured down the drain, depending on the amount of waste you intend to dispose.

References

Relevant Sciencemadness threads