Textbook Question
The following compound has only one asymmetric center. Why then does it have four stereoisomers?
1317
views
Ch. 4 - Isomers: The Arrangement of Atoms in Space
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 5, Problem 41a
Draw the stereoisomers of the following amino acids. Indicate pairs of enantiomers and pairs of diastereomers.
a. 
Verified step by step guidance1
Step 1: Identify the chiral centers in the given amino acid structure. A chiral center is a carbon atom bonded to four different groups. In this structure, the central carbon atom is bonded to a methyl group (CH3), a hydrogen atom (H), an amino group (NH2), and a carboxylic acid group (COOH), making it a chiral center.
Step 2: Determine the possible stereoisomers. A molecule with one chiral center can have two stereoisomers: one with the R configuration and one with the S configuration. These stereoisomers are enantiomers, which are non-superimposable mirror images of each other.
Step 3: Draw the Fischer projections for the two enantiomers. In a Fischer projection, the horizontal bonds represent groups coming out of the plane, and the vertical bonds represent groups going into the plane. Assign the R and S configurations based on the Cahn-Ingold-Prelog priority rules.
Step 4: Consider the possibility of diastereomers. Diastereomers occur when there are multiple chiral centers in a molecule. Since this amino acid has only one chiral center, there are no diastereomers in this case.
Step 5: Label the pairs of enantiomers clearly in your drawings. Indicate which stereoisomer is R and which is S, and ensure the mirror image relationship is evident in the diagrams.
Verified video answer for a similar problem:
This video solution was recommended by our tutors as helpful for the problem above.
Video duration:
2mWas this helpful?
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Stereoisomerism
Stereoisomerism refers to the phenomenon where compounds have the same molecular formula and connectivity of atoms but differ in the spatial arrangement of their atoms. This can lead to different physical and chemical properties. The two main types of stereoisomers are enantiomers, which are non-superimposable mirror images, and diastereomers, which are not mirror images of each other.
Recommended video:
Guided course
01:58
Determining when molecules are stereoisomers.
Chirality
Chirality is a property of a molecule that has a non-superimposable mirror image, often due to the presence of a chiral center, typically a carbon atom bonded to four different substituents. Amino acids are often chiral, leading to two enantiomers (D and L forms) that can have different biological activities. Identifying chirality is crucial for understanding the behavior of amino acids in biological systems.
Recommended video:
Guided course
05:10What is chirality?
Enantiomers and Diastereomers
Enantiomers are pairs of stereoisomers that are mirror images of each other, such as the D and L forms of amino acids. They exhibit identical physical properties except for their interaction with plane-polarized light and reactions in chiral environments. Diastereomers, on the other hand, are stereoisomers that are not mirror images and can have different physical and chemical properties, making their identification important in organic chemistry.
Recommended video:
Guided course
03:44Using chiral centers to predict types of stereoisomers.
Related Practice
Textbook Question
a. Stereoisomers with two asymmetric centers are called ___ if the configuration of both asymmetric centers in one stereoisomer is the opposite of the configuration of the symmetric centers in the other stereoisomer.
b. Stereoisomers with two asymmetric centers are called ___ if the configuration of both asymmetric centers in one stereoisomer is the same as the configuration of the asymmetric centers in the other stereoisomer.
c. Stereoisomers with two asymmetric centers are called ___ if one of the asymmetric centers has the same configuration in both stereoisomers and the other asymmetric center has the opposite configuration in the two stereoisomers.
1509
views
Textbook Question
Draw all possible stereoisomers for each of the following:
b. 2-bromo-4-chlorohexane
1255
views
Textbook Question
Draw the stereoisomers of 2-methylcyclohexanol.
1719
views
Textbook Question
The stereoisomer of cholesterol found in nature is shown here.
a. How many asymmetric centers does cholesterol have?
b. What is the maximum number of stereoisomers that cholesterol can have?
1479
views
Textbook Question
1-Bromo-2-methylcyclopentane has four pairs of diastereomers. Draw the four pairs.
1546
views