Key Reactions and Uses of Ethyl Acetoacetate in Organic Chemistry
Ethyl acetoacetate is an organic compound that is the ethyl ester of acetoacetate. The chemical formula of this compound is C6H10O3 or CH3COOCH2COOC2H5. This compound is present as a colourless liquid with a fruity fragrance that is used as a food flavouring. It is also used as a chemical intermediate for the production of various types of chemical compounds. This compound is also used industrially in the production of synthetic dyes and drugs.
Ethyl acetoacetate is industry produced compound. The ethyl acetoacetate structure is produced using the treatment of ethanol with diketene. The production of this compound in the laboratory is a very well-known procedure. This is done by using the process of Claisen condensation of ethyl acetate.
The reaction produces one molecule of ethyl acetoacetate and one molecule of ethanol from the condensation of two molecules of ethyl acetate.
CH3COOCH2COOC2H5 is a primary part of acetoacetate ester synthesis. Now that you have a brief understanding of this compound and its production. Let’s now learn about acetoacetate ester synthesis.
What is Acetoacetate Ester Synthesis?
Ester synthesis of acetoacetate is a chemical reaction where α-substituted acetone and a ketone are produced by the alkylation of ethyl acetoacetate at the α-carbon to the two types of carbonyl groups.
This chemical reaction uses a strong base that helps deprotonate the dicarbonyl α-carbon. Due to resonance stabilization and enolate conjugation, the dicarbonyl α-carbon is selected over the methyl carbon. The process of preference of one carbon over the other is known as a nucleophilic substitution in this reaction.
When the ester is heated with aqueous acids, it creates a new hydrolyzed β-keto acid from the alkylated ester. The β-keto acid can then be decarboxylated to form methyl ketone.
That is a brief understanding of ester synthesis, which talked about how the synthesis is completed. Each of these compounds is created by their internal molecular and chemical structure; the ethyl acetoacetate structure or the ethyl acetoacetate formula is C6H10O3 or CH3COOCH2COOC2H5. The chemical and molecular acetoacetate structure is C4H5O3-. The acetoacetate structure is derived from the ester synthesis of compounds such as ethyl acetoacetate.
Some Facts About Ethyl Acetoacetate to Better Understand the Compound
These are some of the important facts about the compound that will help you understand how it works with other compounds and its physical and chemical properties.
Ethyl Acetoacetate Reactions: This compound primarily reacts or is more easily introduced in condensation reactions. Reactions that use Claisen condensation widely use this compound as it is a classic laboratory experiment. This compound is generally used for synthesizing furans, pyrroles, pyridines, pyrazoles, purines, and quinolines.
Ethyl Acetoacetate Density: The ethyl acetoacetate density is 1.02 g/cm3. This means the ethyl acetoacetate density is 1.02 grams per cubic centimeter; in comparison, the density of fresh water is 1 gram per cubic centimeter at four degrees centigrade.
Ethyl Acetoacetate MSDS: MSDS stands for Material Safety Data Sheet. The ethyl acetoacetate MSDS states that this compound is combustible in both liquid and vapour forms with a flashpoint (the lowest temperature at which a combustible material can ignite if provided a source for ignition) of 70 degrees centigrade. This compound is also harmful to the respiratory organs of human beings along with their eyes and skin. Acetoacetate causes skin and eye irritation upon exposure. If this compound is ingested, it can cause gastrointestinal problems with vomiting and diarrhoea. In case of inhalation, this compound can lead to respiratory tract irritation with immediate effects such as drowsiness and dizziness. Repeated and prolonged exposure to this compound can lead to the skin being affected by dermatitis.
If you are exposed to ethyl acetoacetate, these are the safety precautions you will need to follow. In case you are caused eye irritation by exposure to this compound, you need to wash your eyes with cold running water for 15 minutes minimum to get rid of the irritation. If the irritation persists, you need medical assistance.
If exposure to this compound causes skin irritation, you need to clean the irritation area with cold water. Following that, removing all clothing items that you were wearing during the exposure to acetoacetate needs to be done. Medical aid is necessary if the skin irritation persists or increases.
In case of ingestion of ethyl acetoacetate, do not induce vomiting and get medical help as quickly as possible.
If you are exposed to this compound through inhalation, you need immediate medical help, but first, safely removing yourself or others from the area of exposure is needed. Oxygen supply might be needed if the person is not able to breathe or is having trouble breathing.
Ethyl Acetoacetate Molar Mass: The ethyl acetoacetate molecular weight is 130.14 g/mol; in comparison, the molar mass of acetoacetic acid is 102.88 g/mol.
Ethyl Acetoacetate Boiling Point: The boiling point of ethyl acetoacetate is 180.8OC. The melting point of this compound is -450C.
Ethyl Acetoacetate IUPAC Name: The IUPAC name of ethyl acetoacetate is ethyl 3-oxobutanoate.
Solved Examples
Q1: What is the Fragrance of Ethyl Acetoacetate?
A) Fruity
B) Pungent
C) Rotten
D) Sweet
Answer: A) Fruity
Q2: What is the IUPAC Name of Ethyl Acetoacetate?
A) 3Ethyl Acetoacetate
B) 4-Oxobutane ethyl
C) ethyl 3-oxobutanoate
D) Butaneoxyethanoate
Answer: C) ethyl 3-oxobutanoate
FAQs on Ethyl Acetoacetate: Structure, Properties & Applications
1. What is ethyl acetoacetate and what is its IUPAC name?
Ethyl acetoacetate is an organic compound, specifically a β-keto ester, with the chemical formula CH₃COCH₂COOC₂H₅. It is a colourless liquid known for its characteristic fruity odour. According to the International Union of Pure and Applied Chemistry (IUPAC) nomenclature, its official name is ethyl 3-oxobutanoate.
2. What are the main physical properties of ethyl acetoacetate?
Ethyl acetoacetate has several distinct physical properties that are important for its identification and use in a laboratory setting. These include:
- Appearance: It is a colourless liquid.
- Odour: It has a pleasant, fruity smell.
- Boiling Point: The boiling point of ethyl acetoacetate is approximately 180.8 °C.
- Density: Its density is 1.02 g/cm³, making it slightly denser than water.
- Molar Mass: The molecular weight of ethyl acetoacetate is 130.14 g/mol.
3. How is ethyl acetoacetate typically prepared in a laboratory?
In a laboratory, ethyl acetoacetate is most commonly prepared through the Claisen condensation reaction. This process involves the self-condensation of two molecules of ethyl acetate (CH₃COOC₂H₅) in the presence of a strong base, such as sodium ethoxide (NaOEt). The base removes a proton from the α-carbon of one ethyl acetate molecule to form an enolate, which then acts as a nucleophile, attacking the carbonyl carbon of a second ethyl acetate molecule. The reaction yields ethyl acetoacetate and ethanol as a byproduct.
4. Why does ethyl acetoacetate exhibit keto-enol tautomerism?
Ethyl acetoacetate exhibits keto-enol tautomerism due to the unique structural feature of its active methylene group (the -CH₂- group situated between two carbonyl groups). The hydrogen atoms on this carbon are particularly acidic because the resulting carbanion (enolate) is stabilised by resonance, delocalising the negative charge over both oxygen atoms of the adjacent carbonyl groups. This allows the compound to exist as an equilibrium mixture of two forms: the keto form (CH₃COCH₂COOC₂H₅) and the more stable (due to conjugation and hydrogen bonding) enol form.
5. What makes ethyl acetoacetate such an important starting material in organic synthesis?
The importance of ethyl acetoacetate as a synthetic reagent stems from its active methylene group. The acidic protons of this group can be easily removed by a base to form a stable enolate ion. This enolate is an excellent nucleophile that can be used in reactions to form new carbon-carbon bonds. This is the principle behind the Acetoacetic Ester Synthesis, a versatile method used to prepare various α-substituted methyl ketones by alkylating the enolate followed by hydrolysis and decarboxylation.
6. What are the primary industrial and commercial uses of ethyl acetoacetate?
Industrially, ethyl acetoacetate is a valuable chemical intermediate. Its primary uses include:
- Chemical Synthesis: It serves as a starting material for manufacturing a wide range of products, including pharmaceuticals (like analgesics), synthetic dyes, and various heterocyclic compounds like pyrazoles and pyridines.
- Paints and Lacquers: It is used in the production of certain types of lacquers and paints.
- Food Industry: Due to its pleasant fruity aroma, it is approved for use in small quantities as a food flavouring agent to impart fruity notes.
7. What are the key safety hazards associated with handling ethyl acetoacetate?
Ethyl acetoacetate is a combustible liquid and presents several health hazards. According to its Material Safety Data Sheet (MSDS), key precautions are necessary because it can cause:
- Irritation: It is an irritant to the skin and eyes upon direct contact.
- Respiratory Issues: Inhalation of its vapours can cause irritation to the respiratory tract, leading to symptoms like dizziness and drowsiness.
- Gastrointestinal Problems: If ingested, it can cause significant gastrointestinal irritation.
Therefore, it must be handled in a well-ventilated area, and personal protective equipment such as safety goggles and gloves should be worn.
