Final Lab Report

Fischer Esterification using Unknown Alcohol # 3 and Acetic Acid

Writer: Alyssa Rutkoski

Reviewer: Lauren Hawkins

Editor: Pam Rodriguez

Introduction:

Fischer Esterification is the addition or degradation reaction which combines a carboxylic acid along with an alcohol. This replaces the hydroxyl group of the carboxylic acid with an alkoxide group. The alkoxide group is the conjugate base of the alcohol. The reaction is typically acid-catalyzed with HCl but in this lab it will be concentrated H2SO4. The reaction exists in equilibrium, due to Le Chatline’s Principle, adding excess reactant or removing a product as it is formed will shift the equilibrium to the side of the product. Esters are part of the family of carboxylic acid derivatives. They occur in a wide variety of naturally occurring odors and flavors. Most odors and flavors are the result of a complex mixture with one ester dominating. A list of common esters used in the fragrance industry are listed in figure 1.

Esters are a common derivative of carboxylic acids. They occur in a large variety of naturally occurring odors and flavorings. Where most odors and flavors are the result of a complex mixture, with only one ester predominating. Esters are easy to synthesize. Some common esters used in the fragrance industry, which can be seen in figure 1.1

Figure 1. This figure depicts the common esters used by the fragrance industry and its properties.

Esters can be synthesized by reacting alcohols with carboxylic acids, only in the presence of a catalytic amount of a strong acid. This specific reaction is reversible, and the alcohol, carboxylic acid, and ester are present at equilibrium. For the maximization to forward the reaction, an excess of one of the starting materials is often added.

Fischer Esterification is a basic condensation reaction between a carboxylic acid and an alcohol to form an ester. Fischer Esterification is the addition or degradation reaction which combines a carboxylic acid along with an alcohol. This replaces the hydroxyl group of the carboxylic acid with an alkoxide group. The alkoxide group is the conjugate base of the alcohol. The reaction is typically acid-catalyzed with HCl but in this lab it will be concentrated H2SO4. The reaction will shift toward products in order to establish the equilibrium. This can be seen in figure 2.1

Figure 2: This figure depicts the general Esterification reaction and since the reaction is reversible, there will be an excess of the carboxylic acid that will be added.

The reagents and their properties utilized in this lab are shown in table 1.

Table 1: Table of Reagents

Compound

M/W g/mol

BP

MP

AMT USED

Amyl alcohol

88.15

136-138

Isoamyl alcohol

88.15

130-132

Propyl alcohol

60.10

97-97.2

Butyl alcohol

74.12

116-118

Isobutyl alco