![Organic Chemistry (8th Edition)](https://www.bartleby.com/isbn_cover_images/9780134042282/9780134042282_largeCoverImage.gif)
Concept explainers
Interpretation:
The percentage of molecules of trans-1,2-dimethycyclohexane has to be calculated.
Concept introduction:
Strain energy: Ring strain is a type of instability that exists when bonds in a molecule form angles that are abnormal. Strain is most commonly discussed for small rings such as cyclopropanes and cyclobutanes, whose internal angles are substantially smaller than the idealized value of approximately 109°.
Angle strain of cyclic molecules: The German chemist Adolf van Baeyer, believing that all cyclic molecules like planner, proposed that the stability of a cycloalkane could be predicated by determining the difference between this ideal bond angle and the bond angle in the planner cycloalkane.
We consider the simple example of the bond angle in cyclopropane are 600 degree repressing a 45.50 degree it deviation from 109.50, it is proved from Baeyer this deviation cause angle strain which decrease respective molecules stability.
The corresponding Bond strain formula shown below
Chair conformers: The cyclic compounds most commonly found in nature contain six-membered rings because carbon rings of that size can exist in conformation called a chair conformer that is almost completely free of ring strain.
Boat conformer: The boat conformers is further destabilized by the close proximity of the flagpole hydrogens the hydrogens at the “bow” and “stern” of the boat which cause steric strain.
![Check Mark](/static/check-mark.png)
Want to see the full answer?
Check out a sample textbook solution![Blurred answer](/static/blurred-answer.jpg)
Chapter 3 Solutions
Organic Chemistry (8th Edition)
- As we learned in Chapter 4, monosubstituted cyclohexanes exist as an equilibrium mixture of two conformations having either an axial or equatorial substituent. When R = CH2CH3, Keq for this process is 23.When R = C(CH3)3, Keq for this process is 4000. a.When R = CH2CH3, which conformation is present in higher concentration? b.Which R shows the higher percentage of equatorial conformation at equilibrium? c. Which R shows the higher percentage of axial conformation at equilibrium? d. For which R is ΔGo more negative? e.How is the size of R related to the amount of axial and equatorial conformations at equilibrium?arrow_forward9. There are several possible forms of a trisubstituted cyclohexane with the formula C10H200. I have drawn four of them. From these, which one do you think is most commonly naturally occurring, and why? Which is least commonly occurring and why? HO HO" НО HOarrow_forwardDraw the line bond structures for the following alkenes, cyclic alkenes, and alkynes: Can you explain to me about this part A) noncyclic alkenes that contain 4 carbon atoms (3 possible), please? Can you explain to me about this part B) cyclic alkenes that contain 4 carbon atoms (4 possible), please? Can you explain to me about this part C) alkynes that contain 4 carbon atoms (2 possible, neither of them is a cyclic alkyne), please?arrow_forward
- 15. For the molecules:2,2-dimethylhexane, and octane. Which of the 2,3,4-trimethylpentane following structures will have the highest bp, lowest mp, and the least soluble in water?arrow_forwardH2. Please give typed answerarrow_forwardG fic Gb| xnx # 3 III 80 F3 |DC|OU| BAX GdH2|GD|GB|GP|BW|G1|CS|UONEE Question 20 of 31 Provide the correct IUPAC name for the compound shown here. 1,1- 3- 3-1- 2- 1,2- 4- sec- cyclo tert- tri iso di but pent pent meth hex prop eth 99 11 MacBook Air V $ C 4 V Q F4 Aa DO LO % 5 F5 CO 6 Si F6 & 7 F7 8 DII F8 9 F9 0 F10 Donearrow_forward
- Why is a substituted cyclohexane ring more stable with a larger group in the equatorial position?arrow_forwardsketch the various conformational isomers of 1,3-dimethylcyclohexane. Indicate the position (axial/equatorial) of each of the methyl groups in each structure.arrow_forward1. The energy barrier for carbon-carbon bond rotation in propane is mainly due to 2. Which of the following correctly ranks the cycloalkanes in order of increasing ring strain per methylene'? A) cyclopropane < cyclobutane < cyclohexane < cyclopentane B) cyclohexane < cyclopentane < cyclobutane < cyclopropane C) cyclohexane < cyclobutane < cyclopentane < cyclopropane D) cyclopentane < cyclopropane < cyclobutane < cyclohexane E) cyclopropane < cyclopentane < cyclobutane < cyclohexane 3. Which of the statements correctly describes the chair conformations of trans-1,3-diethylcyclohexane? A) The two chair conformations are equal in energy. B) The higher energy chair conformation contains two axial ethyl groups. C) The higher energy chair conformation contains two equatorial ethyl groups. D) The lower E) The lower energy chair conformation contains two equatorial ethyl groups. chair conformation contains two axial ethyl groups. energy 4. Provide the IUPAC name for the compounds below. CH3…arrow_forward
- 5. Assume that the types of strain in the rotation about the C1-C2 bond in 1,2-dibromopropane have the following values. •Torsional strain = 20 kJ/mol •Steric strain between two Br substituents gauche = 13 kJ/mol •Steric strain between two Br substituents eclipsed = 16 kJ/mol •Steric strain between Br and CH3 substituents gauche = 8 kJ/mol •Steric strain between Br and CH3 substituents eclipsed (a) Perform a conformational analysis about the C1-C2 bond, analogous to the diagram in Figures 4-4 and 4-7 (Karty). Draw a full rotational energy profile (add E values in kJ/mol on y-axis) drawing each eclipsed and staggered conformation as Newmann projections i.e. 60° rotations for complete rotation about the C1-C2 bond. = 10 kJ/mol. E (kJ/mol) 0° 360 °arrow_forwardThe energy difference between a tert-butyl group going from equatorial to axial in a cyclohexane is 18.3 kJ/mol. When two of the carbon atoms are replaced with oxygen atoms (molecule B) the energy difference between the two chair conformations drops to 5.9 kJ/mol. Explain this difference. (Hint: Consider what makes putting groups axial unfavorable).arrow_forwardThe molar heat of combustion of gaseous cyclopropaneis -2089 kJ/mol; that for gaseous cyclopentane is-3317 kJ/mol. Calculate the heat of combustion per CH2group in the two cases, and account for the difference.arrow_forward
- Organic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage LearningIntroductory Chemistry: A FoundationChemistryISBN:9781337399425Author:Steven S. Zumdahl, Donald J. DeCostePublisher:Cengage Learning
- Organic Chemistry: A Guided InquiryChemistryISBN:9780618974122Author:Andrei StraumanisPublisher:Cengage LearningChemistryChemistryISBN:9781305957404Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCostePublisher:Cengage LearningChemistry: An Atoms First ApproachChemistryISBN:9781305079243Author:Steven S. Zumdahl, Susan A. ZumdahlPublisher:Cengage Learning
![Text book image](https://www.bartleby.com/isbn_cover_images/9781305580350/9781305580350_smallCoverImage.gif)
![Text book image](https://www.bartleby.com/isbn_cover_images/9781337399425/9781337399425_smallCoverImage.gif)
![Text book image](https://www.bartleby.com/isbn_cover_images/9781133951889/9781133951889_smallCoverImage.gif)
![Text book image](https://www.bartleby.com/isbn_cover_images/9780618974122/9780618974122_smallCoverImage.gif)
![Text book image](https://www.bartleby.com/isbn_cover_images/9781305957404/9781305957404_smallCoverImage.gif)
![Text book image](https://www.bartleby.com/isbn_cover_images/9781305079243/9781305079243_smallCoverImage.gif)