What is the role of abs. ethanol in Fischer Esterification to produce Benzocaine?

Question

Jacob Anderson · Accepted Answer

The absolute ethanol has three functions in the Fischer esterification to produce benzocaine.

The reaction's equation is as follows: #underbrace("H"_2"NC"_6"H"_4"COOH")_color(red)(p"-aminobenzoic acid") + "HOCH"_2"CH"_3 stackrelcolor(blue)("H"^+color(white)(m))(⇌)underbrace("H"_2"NC"_6"H"_4"COOCH"_2"CH"_3)_color(red)("benzocaine") + "H"_2"O"# 1. The ethyl ester is formed by the reaction of ethanol. 2. The ethanol acts as a solvent because it is most likely an excess reactant. The most important reason for using absolute ethanol is that the Fischer esterification is an equilibrium reaction with a #K_"eq" ≈ 4#. The five percent water will cause the position of equilibrium to shift slightly to the left and reduce your yield if you use regular 95% ethanol as the reactant. Since there is no water in absolute alcohol, the reaction can proceed even further to the right. For a good yield, you won't need to use as much excess ethanol.

Ava Andrews · Answer

undefined Absolute ethanol serves as a solvent in Fischer Esterification, facilitating the reaction between p-aminobenzoic acid and ethanol to produce benzocaine.