Benzocaine

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Revision as of 15:01, 27 January 2016 by Crystal grower (Talk | contribs) (Safety)

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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.

Benzocaine
220px-Benzocaine.svg.png
Names
IUPAC name
Ethyl 4-aminobenzoate
Systematic IUPAC name
Ethyl 4-aminobenzoate
Properties
C 9 H 11 NO 2
Molar mass 165.189 g/mol
Density 1.17g/cm3
Melting point 89 °C
Boiling point 310 °C
slightly soluble in water.
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

(Introduction)

Properties

Benzocaine is the ethyl ester of p-aminobenzoic acid (PABA). It can be prepared from PABA and ethanol[1] by Fischer esterification or via the reduction of ethyl p-nitrobenzoate. Benzocaine is sparingly soluble in water; it is more soluble in dilute acids and very soluble in ethanol, chloroform and ethyl ether.

Availability

In 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

Handling

Safety

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

Storage

Disposal

References

Relevant Sciencemadness threads