Textbook Question
Identify the alkene that would react with Ti(OiPr)₄, (+) -diethyltartrate, and t-butylhydroperoxide to give the following chiral, nonracemic epoxides.
(c)
2
views
Ch. 9 - Alkenes II: Oxidation and Reduction
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
Chapter 8, Problem 40b
Identify the alkene that would react with Ti(OiPr)4, (+) -diethyltartrate, and t-butylhydroperoxide to give the following chiral, nonracemic epoxides.
(b) 
Verified step by step guidance1
Recognize that the problem involves the Sharpless epoxidation, a method for the enantioselective epoxidation of allylic alcohols using a titanium catalyst, a chiral tartrate ester, and an oxidizing agent.
Identify the reagents: Ti(OiPr)4 is titanium isopropoxide, (+)-diethyltartrate is the chiral ligand, and t-butylhydroperoxide is the oxidizing agent.
Understand that the reaction is stereospecific and will produce an epoxide with a specific stereochemistry based on the chirality of the tartrate used.
Analyze the given chiral epoxide structure to determine the stereochemistry of the epoxide group. This will help in identifying the correct alkene precursor.
Determine the structure of the alkene that would lead to the given epoxide by considering the position of the double bond in relation to the hydroxyl group in the allylic alcohol precursor. The double bond should be adjacent to the hydroxyl group to allow for the formation of the epoxide with the correct stereochemistry.
Verified video answer for a similar problem:
This video solution was recommended by our tutors as helpful for the problem above.
Video duration:
7mWas this helpful?
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Epoxidation
Epoxidation is a chemical reaction that converts alkenes into epoxides, which are three-membered cyclic ethers. This reaction typically involves the addition of an oxygen atom across the double bond of the alkene, resulting in a highly reactive epoxide. The reaction can be facilitated by various reagents, including peracids or metal catalysts, and is significant in organic synthesis for creating chiral centers.
Recommended video:
Guided course
02:19
General properties of epoxidation.
Chirality and Stereochemistry
Chirality refers to the geometric property of a molecule having non-superimposable mirror images, known as enantiomers. In organic chemistry, chirality is crucial for understanding the behavior of molecules in biological systems, as different enantiomers can have vastly different effects. The stereochemistry of a reaction, including the configuration of chiral centers, is essential for predicting the outcome of reactions, such as the formation of nonracemic products.
Recommended video:
1:21Polymer Stereochemistry Example 1
Ti(OiPr)4 and Asymmetric Catalysis
Titanium isopropoxide (Ti(OiPr)4) is a common catalyst used in asymmetric synthesis, particularly in the formation of chiral epoxides. It facilitates the reaction by coordinating to the alkene and directing the addition of the oxidizing agent in a stereoselective manner. The use of chiral ligands, such as (+)-diethyltartrate, enhances the selectivity of the reaction, leading to the formation of nonracemic products with defined stereochemistry.
Recommended video:
2:31Nucleophilic Catalysis Concept 1
Related Practice
Textbook Question
Conjugated dienes, molecules containing two alkenes separated by one single bond, are discussed in detail in Chapter 21.
(b) How might you account for this difference in stability?
2
views
Textbook Question
Calculate the oxidation number for the indicated carbons.
(a)
1
views
Textbook Question
The chiral catalyst (R)-BINAP(COD)RhOTf was used in a hydrogenation reaction as part of the synthesis of fragment C of indinavir. Using the same alkene, predict the product that would be obtained if (S)-BINAP(COD)RhOTf were used instead.
1
views
Textbook Question
Identify the alkene that would react with Ti(OiPr)₄, (+) -diethyltartrate, and t-butylhydroperoxide to give the following chiral, nonracemic epoxides.
(a)
1
views
Textbook Question
Questions (a)–(d) all refer to the following reaction, which has been engineered to produce one enantiomer to the exclusion of the other.
(c) Suppose the difference in activation energy is 1.6 kcal/mol. At what temperature would you produce C in 99% ee?
2
views