The Aldehyde Enigma
Esmeralda Curiel
Organic Chemistry
November 11, 2014
Experiment 62 – The Aldehyde Enigma
INTRODUCTION
In the Cannizaro reaction an aldehyde is simultaneously reduced into its primary alcohol form and also oxidized into it 's carboxylic acid form. The purpose of this experiment is to isolate, purify and identify compounds 1 and 2 which contain 4-chlorobenzaldehyde, methanol, and aqueous potassium hydroxide. Compounds 1 and 2 are purified by crystallization. . The purified product will be characterized by IR spectroscopy and melting point.
As detailed in Pavia 's Organic Laboratory techniques the reaction is expected to proceed via the following reaction: Aqueous Organic
The mechanism is shown below:
PROCEDURE
The experiment was conducted using the procedures detailed in pages 520-522 of
Pavia D., Lampman G. M., Kriz G. S., and Engel R. G. A Small Scale Approach to Organic Laboratory Techniques, Third Edition).
This experiment was performed in collaboration with Paula Mendoza. Exceptions to the procedure are: no NMR or wet chemical test for both compounds. Since there was a lack of organic compound we were unable to proceed with any of the identifying tests.
RESULTS
Key quantities and properties for this experiment are summarized in Tables 1-3. Relevant chemical quantities and properties are presented in Table 1, table 2 contains the summary of characterization results. Table 3 contains the summary of the characterization results. Relevant experimental observations performed during the experiment are described in Table 4.
Table 1: Relevant chemical quantities and properties
Compound
Quantities
Physical characteristics
4-Chlorobenzaldehyde
1.5 g
White powder
Methanol
4.0 mL
Clear liquid
Potassium hydroxide
4.0 mL
Clear liquid
Methylene chloride
20.0 mL
Clear liquid
5% Sodium bicarbonate
20.0 mL
Clear liquid
4-chlorobenzoic acid
N/A
Small white powder crystals
Organic Chemistry
November 11, 2014
Experiment 62 – The Aldehyde Enigma
INTRODUCTION
In the Cannizaro reaction an aldehyde is simultaneously reduced into its primary alcohol form and also oxidized into it 's carboxylic acid form. The purpose of this experiment is to isolate, purify and identify compounds 1 and 2 which contain 4-chlorobenzaldehyde, methanol, and aqueous potassium hydroxide. Compounds 1 and 2 are purified by crystallization. . The purified product will be characterized by IR spectroscopy and melting point.
As detailed in Pavia 's Organic Laboratory techniques the reaction is expected to proceed via the following reaction: Aqueous Organic
The mechanism is shown below:
PROCEDURE
The experiment was conducted using the procedures detailed in pages 520-522 of
Pavia D., Lampman G. M., Kriz G. S., and Engel R. G. A Small Scale Approach to Organic Laboratory Techniques, Third Edition).
This experiment was performed in collaboration with Paula Mendoza. Exceptions to the procedure are: no NMR or wet chemical test for both compounds. Since there was a lack of organic compound we were unable to proceed with any of the identifying tests.
RESULTS
Key quantities and properties for this experiment are summarized in Tables 1-3. Relevant chemical quantities and properties are presented in Table 1, table 2 contains the summary of characterization results. Table 3 contains the summary of the characterization results. Relevant experimental observations performed during the experiment are described in Table 4.
Table 1: Relevant chemical quantities and properties
Compound
Quantities
Physical characteristics
4-Chlorobenzaldehyde
1.5 g
White powder
Methanol
4.0 mL
Clear liquid
Potassium hydroxide
4.0 mL
Clear liquid
Methylene chloride
20.0 mL
Clear liquid
5% Sodium bicarbonate
20.0 mL
Clear liquid
4-chlorobenzoic acid
N/A
Small white powder crystals