Benzocaine
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.
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| Names | |
|---|---|
| IUPAC name
Ethyl 4-aminobenzoate
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| 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)
Contents
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.
