Textbook Question
Indicate how the following compounds can be synthesized from cyclohexanone and any other necessary reagents:
d.
2
views
Ch. 17 - Reactions at the Alpha-Carbon
Bruice8th EditionOrganic ChemistryISBN: 9780135213711
Not the one you use?Change textbookSelect a different textbook
Table of contents
- Ch. 1 - Remembering General Chemistry: Electronic Structure and Bonding (Part 1)31
- Ch. 1 - Remembering General Chemistry: Electronic Structure and Bonding (Part 2)65
- Ch. 2 - Acids and Bases: Central to Understanding Organic Chemistry84
- Ch. 3 - An Introduction to Organic Compounds:Nomenclature, Physical Properties, and Structure183
- Ch. 4 - Isomers: The Arrangement of Atoms in Space121
- Ch. 5 - Alkenes: Structure, Nomenclature, and an Introduction to Reactivity • Thermodynamics and Kinetics83
- Ch. 6 - The Reactions of Alkenes • The Stereochemistry of Addition Reactions175
- Ch. 7 - The Reactions of Alkynes • An Introduction to Multistep Synthesis119
- Ch. 8 - Delocalized Electrons: Their Effect on Stability, pKa, and the Products of a Reaction • Aromaticity and Electronic Effects: An Introduction to the Reactions of Benzene148
- Ch. 9 - Substitution and Elimination Reactions of Alkyl Halides212
- Ch. 10 - Reactions of Alcohols, Ethers, Epoxides, Amines, and Sulfur-Containing Compounds131
- Ch. 11 - Organometallic Compounds60
- Ch. 12 - Radicals90
- Ch. 13 - Mass Spectrometry; Infrared Spectroscopy; UV/Vis Spectroscopy62
- Ch. 14 - NMR Spectroscopy95
- Ch. 15 - Reactions of Carboxylic Acids and Carboxylic Acid Derivatives123
- Ch. 16 - Reactions of Aldehydes and Ketones • More Reactions of Carboxylic Acid Derivatives141
- Ch. 17 - Reactions at the Alpha-Carbon101
- Ch. 18 - Reactions of Benzene and Substituted Benzenes144
- Ch. 19 - More About Amines • Reactions of Heterocyclic Compounds49
- Ch. 20 - The Organic Chemistry of Carbohydrates80
- Ch. 21 - Amino Acids, Peptides, and Proteins57
- Ch. 22 - Catalysis in Organic Reactions and in Enzymatic Reactions35
- Ch. 23 - The Organic Chemistry of the Coenzymes—Compounds Derived from Vitamins1
- Ch. 28 - Pericyclic Reactions58
Chapter 18, Problem 68
The ketone whose 1H NMR spectrum is shown here was obtained as the product of an acetoacetic ester synthesis. What alkyl halide was used in the synthesis?
<IMAGE>
Verified step by step guidance1
Step 1: Analyze the molecular formula provided in the image, C₅H₁₀O, which indicates the compound is a ketone with five carbons, ten hydrogens, and one oxygen atom.
Step 2: Examine the ¹H NMR spectrum. The spectrum shows three distinct signals: a singlet at approximately 2.1 ppm (3H), a quartet at approximately 2.4 ppm (2H), and a triplet at approximately 1.0 ppm (3H). These signals correspond to different proton environments in the molecule.
Step 3: Interpret the singlet at 2.1 ppm (3H). This signal is characteristic of a methyl group directly attached to a carbonyl group (CH₃-C=O), which is consistent with the ketone functional group.
Step 4: Analyze the quartet at 2.4 ppm (2H) and the triplet at 1.0 ppm (3H). These signals suggest the presence of an ethyl group (-CH₂-CH₃) attached to the molecule. The quartet corresponds to the CH₂ group adjacent to the carbonyl group, and the triplet corresponds to the CH₃ group further away.
Step 5: Based on the acetoacetic ester synthesis mechanism, the alkyl halide used must introduce the ethyl group into the molecule. Therefore, the alkyl halide used in the synthesis is ethyl bromide (CH₃CH₂Br).
Verified video answer for a similar problem:
This video solution was recommended by our tutors as helpful for the problem above.
Video duration:
9mWas this helpful?
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Acetoacetic Ester Synthesis
Acetoacetic ester synthesis is a method for synthesizing ketones through the reaction of an acetoacetic ester with an alkyl halide. This process involves the formation of a β-keto ester, which can be hydrolyzed and decarboxylated to yield the desired ketone. Understanding this synthesis is crucial for identifying the starting materials and the resulting products in organic reactions.
Recommended video:
01:28
Synthesis of Amino Acids: Acetamidomalonic Ester Synthesis Example 2
NMR Spectroscopy
Nuclear Magnetic Resonance (NMR) spectroscopy is a powerful analytical technique used to determine the structure of organic compounds. In 1H NMR, the chemical environment of hydrogen atoms is analyzed, providing information about the number of hydrogen atoms, their connectivity, and the presence of functional groups. Peaks in the spectrum correspond to different hydrogen environments, which are essential for deducing the structure of the synthesized ketone.
Recommended video:
Guided course
10:06General NMR Features
Alkyl Halides in Organic Synthesis
Alkyl halides are organic compounds containing a carbon atom bonded to a halogen atom (F, Cl, Br, I). They are commonly used as electrophiles in nucleophilic substitution reactions, making them key reagents in organic synthesis. Identifying the specific alkyl halide used in the acetoacetic ester synthesis is critical for understanding the reaction pathway and the final structure of the ketone produced.
Recommended video:
Guided course
01:52How to name alkyl halides
Related Practice
Textbook Question
The Reformatsky reaction is an addition reaction in which an organozinc reagent is used instead of a Grignard reagent to add to the carbonyl group of an aldehyde or a ketone. Because the organozinc reagent is less reactive than a Grignard reagent, a nucleophilic addition to the ester group does not occur.
The organozinc reagent is prepared by treating an α-bromo ester with zinc.
Describe how each of the following compounds can be prepared, using a Reformatsky reaction:
c.
1
views
Textbook Question
The Reformatsky reaction is an addition reaction in which an organozinc reagent is used instead of a Grignard reagent to add to the carbonyl group of an aldehyde or a ketone. Because the organozinc reagent is less reactive than a Grignard reagent, a nucleophilic addition to the ester group does not occur. The organozinc reagent is prepared by treating an α-bromo ester with zinc.
Describe how each of the following compounds can be prepared, using a Reformatsky reaction:
a.
5
views
Textbook Question
Compound A with molecular formula C6H10 has two peaks in its 1H NMR spectrum, both of which are singlets (with ratio 9 : 1). Compound A reacts with an acidic aqueous solution containing mercuric sulfate to form compound B, which gives a positive iodoform test (Problem 58) and has an 1H NMR spectrum that shows two singlets (with ratio 3 : 1). Identify A and B.
3
views
Textbook Question
b. What carboxylic acid is formed when the malonic ester synthesis is carried out with two equivalents of malonic ester, one equivalent of 1,5-dibromopentane, and two equivalents of base?
4
views
Textbook Question
Indicate how each of the following compounds can be synthesized from the given starting material and any other necessary reagents:
c.
1
views