Textbook Question
A student, when solving the following 'predict-the-product' question, made a common mistake by writing the answer shown here. Explain why this reaction would not work as written.
10
views
Ch. 17 - Carbonyl Addition Reactions: Aldehydes and Ketones
Mullins1st EditionOrganic Chemistry: A Learner Centered ApproachISBN: 9780137566471
Not the one you use?Change textbookSelect a different textbook
Table of contents
- Ch. 2 - General Chemistry Translated: Finding the Electrons114
- Ch. 3 - Alkanes and Cycloalkanes: Properties and Conformational Analysis109
- Ch. 4 - Acids and Bases: Electron Flow144
- Ch. 5 - Chemical Reaction Analysis: Thermodynamics and Kinetics118
- Ch. 6 - Stereoisomerism: Arrangement of Atoms in Space112
- Ch. 7 - Principles of Green (Organic) Chemistry3
- Ch. 8 - Alkenes I: Properties and Electrophilic Additions158
- Ch. 9 - Alkenes II: Oxidation and Reduction150
- Ch. 10 - Alkynes: Electrophilic Addition and Redox Reactions101
- Ch. 11 - Properties and Synthesis of Alkyl Halides: Radical Reactions108
- Ch. 12 - Substitution and Elimination: Reactions of Haloalkanes172
- Ch. 13 - Alcohols, Ethers and Related Compounds: Substitution and Elimination239
- Ch. 14 - Structural Identification I: Infrared Spectroscopy and Mass Spectrometry54
- Ch. 15 - Structural Identification II: Nuclear Magnetic Resonance Spectroscopy93
- Ch. 16 - Metals in Organic Chemistry48
- Ch. 17 - Carbonyl Addition Reactions: Aldehydes and Ketones45
- Ch. 18 - Nucleophilic Acyl Substitution I: Carboxylic Acids18
- Ch. 19 - Nucleophilic Acyl Substitution II: Carboxylic Acid Derivatives39
- Ch. 20 - Enolates: Carbonyl Addition and Substitution13
- Ch. 21 - Conjugated Systems I: Stability and Addition Reactions56
- Ch. 22 - Conjugated Systems II: Pericyclic Reactions54
- Ch. 23 - Benzene I: Aromatic Stability and Substitution Reactions64
- Ch. 24 - Benzene II: Reactions Influenced by the Aromatic Ring62
- Ch. 25 - Amines: Structure, Reactions, and Synthesis27
- Ch. 26 - Amino Acids, Proteins, and Peptide Synthesis9
- Ch. 27 - Carbohydrates, Nucleic Acids, and Lipids54
Mullins1st EditionOrganic Chemistry: A Learner Centered ApproachISBN: 9780137566471Not the one you use?Change textbook
All textbooks
Mullins 1st EditionCh. 17 - Carbonyl Addition Reactions: Aldehydes and KetonesProblem 20b
Mullins 1st EditionCh. 17 - Carbonyl Addition Reactions: Aldehydes and KetonesProblem 20bChapter 16, Problem 20b
Suggest an acetylide ion and a carbonyl that might be used to make the following products.
(b) 2,6-dimethylhept-3-yn-2-ol
Verified step by step guidance1
Identify the structure of the target molecule, 2,6-dimethylhept-3-yn-2-ol. It contains a terminal alcohol group (-OH) at carbon 2, a triple bond between carbons 3 and 4, and methyl groups attached to carbons 2 and 6.
Recall that acetylide ions (R-C≡C⁻) are strong nucleophiles that can attack electrophilic carbonyl carbons (C=O) to form alcohols after protonation. The triple bond in the product suggests the use of an acetylide ion.
Break the target molecule into two fragments: (1) the acetylide ion and (2) the carbonyl compound. The bond between the carbon bearing the alcohol group (C2) and the adjacent carbon (C3) is likely formed during the reaction.
Determine the acetylide ion: The fragment containing the triple bond and the terminal carbon (C≡C-CH(CH₃)₂) corresponds to the acetylide ion. This is derived from 2-methylbut-1-yne by deprotonation with a strong base like NaNH₂.
Determine the carbonyl compound: The remaining fragment, a ketone, corresponds to 3-methylbutan-2-one. This ketone reacts with the acetylide ion in a nucleophilic addition reaction to form the target alcohol after protonation.
Verified video answer for a similar problem:
This video solution was recommended by our tutors as helpful for the problem above.
Video duration:
4mWas this helpful?
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Acetylide Ion
An acetylide ion is a negatively charged species formed by deprotonating a terminal alkyne. It is a strong nucleophile, capable of attacking electrophilic carbon centers, such as those found in carbonyl compounds. In organic synthesis, acetylide ions are often used to form carbon-carbon bonds, making them essential for constructing complex molecules.
Recommended video:
3:39
Metal Ion Catalysis Concept 1
Carbonyl Compounds
Carbonyl compounds contain a carbon atom double-bonded to an oxygen atom (C=O). They include aldehydes, ketones, and carboxylic acids, and are key intermediates in organic synthesis. The electrophilic nature of the carbonyl carbon allows it to react with nucleophiles, such as acetylide ions, facilitating the formation of alcohols and other functional groups.
Recommended video:
Guided course
01:40Defining meso compounds.
Synthesis of Alcohols
The synthesis of alcohols from carbonyl compounds typically involves nucleophilic addition reactions. When an acetylide ion attacks a carbonyl carbon, it forms an alkoxide intermediate, which can be protonated to yield an alcohol. This reaction is fundamental in organic chemistry for constructing alcohols with specific carbon skeletons, such as the target compound in the question.
Recommended video:
Guided course
02:26Forming alcohols through Oxymercuration-Reduction.
Related Practice
Textbook Question
Suggest an acetylide ion and a carbonyl that might be used to make the following products.
(c) 5-phenylhex-2-yn-1-ol
1
views
Textbook Question
Suggest a carbonyl to react with NaCN/HCN to produce the following cyanohydrins.
(a)
1
views
Textbook Question
Classify the following nucleophiles as strong, weak, or intermediate. Would you expect each to add to a carbonyl directly or wait for a carbocation to form?
(d)
1
views
Textbook Question
Suggest an acetylide ion and a carbonyl that might be used to make the following products.
(a) oct-4-yn-3-ol
2
views
Textbook Question
For each of the following carbonyl addition reactions, would you expect a racemic mixture or a mixture enriched in one stereoisomer? In each case, draw both possible stereoisomeric products.
(a)
2
views