Concept explainers
Interpretation:
The Newman projections of
Concept introduction:
Newman projections are used to show the relative positions of the groups attached to the two carbon atoms of the bond of interest. The representation is drawn looking along the bond. The carbon in front is represented by a point, while the carbon at the back is represented by a concentric circle. The bonds to the three groups on the front carbon converge on the point. Bonds to the three groups on the back carbon end on the circle. Depending on the dihedral angles, the conformers are classified as eclipsed or staggered with angles of
Depending on the relative positions of the bulkiest groups on the front and back carbon, the staggered conformers are further divided into anti and gauche. In anti-conformers, the bulkiest groups on the front and back carbons are directly across from each other with a
A molecule possesses a plane of symmetry if a plane passing through its center divides it into halves that are mirror images of each other.
Want to see the full answer?
Check out a sample textbook solutionChapter 5 Solutions
Organic Chemistry: Principles and Mechanisms (Second Edition)
- Consider 1-bromo-2-methylpropane and draw the following. (a) The staggered conformation(s) of lowest energy (b) The staggered conformation(s) of highest energyarrow_forwardcalculate the amount of steric strain in each of the chair conformers of 1,1,3-trimethylcyclohexane. Which conformer predominates at equilibrium?arrow_forwardThe overall process of converting one chair conformation to another chair conformation is known as RING INVERSION or ring flipping and is a very rapid process. The cyclohexane ring inverts approximately 10 time a second at room temperature. Show this interconversion by drawing the two chair conformations and putting a reversible arrow between them to indicate a dynamic equilibrium. If we have a methylcyclohexane molecule and this undergoes ring inversion, whatwill be the resulting structure? ?arrow_forward
- Is there a difference in the stability of the two cyclohexane conformations?arrow_forwardAcetylcholine is a neurotransmitter in the central nervous system in humans. Sighting along the C-C bond, draw Newman projection formulas for all the eclipsed and staggered conformers of acetylcholine. Which among the conformers is the least stable? The most stable? Plot a conformational analysis for these conformers.arrow_forwardStarting with the chair conformer shown on the left, provide a potential energy plot for the chair-to-chair flip of that conformer. Label each of conformers by name. Present appropriate relative energies by the positioning of each conformer on your plot, assuming that all of the isotopes of hydrogen are the same size. T Darrow_forward
- Draw Newman projections for the anti, eclipsed, gauche and fully eclipsed conformations of Butane. Indicate their relative stabilities and the reasons for your ranking-need to discuss the stresses involved in each case. Using suitable specific conformers of specific structures as examples, explain the difference between (a) angle strain (b) torsional strain and (c) steric strain. Need to draw the confomers and structures 4) Draw the most stable conformers using chair structures of the following: (c) cis-1,2-Dibromocyclohexane (d) trans-1,2-Dibromocyclohexane (e) cis-Decalin (f) trans-Decalin . Draw the most stable conformers of trans-1-Bromo-4-methylcyclohexane and cis-1-Bromo-4-methylcyclohexane. Which is more stable? Explain the reason for your answer. Need to include a discussion of 1,3-Diaxial interactionarrow_forward1. The structure shown below is a dioxane, and it exists in a chair conformation just like cyclohexane. The specific compound is cis-2-methyl-5-tert-butyl-1,3-dioxane. Draw the two chair conformations of this compound. Surprisingly, the conformer with the tert-butyl group in an axial position is preferred. Circle the preferred conformer. In one sentence or less, explain of this observation. C(CH3)3 CH3arrow_forwardDraw all Newman projections of 2,2 bromopropane conformations in which the CH3 group and the H of the CHY2 group are positioned 'gauche' to each other.arrow_forward
- Given cyclohexane in a chair conformation, construct the more stable conformation of cis‑1‑methyl‑2‑propylcyclohexane by filling in the missing atoms or groups. Use the numbering provided on the ring.arrow_forwardDescribe the conformations of the following: E) Gauche conformation of ethane, (ü) felipsed conformation of ethene, (iii) Staggered conformation of propane, (iv) Syn- and anti-conformation of butane.arrow_forwardHello, I was reading an answer from the book Organic Chemistry by Brown et al. The question is 2.51 "Draw alternative chair conformations for each substituted cyclohexane and state which chair is more stable." There are then 4 cyclohexanes (labeled a-d). For the "a" cyclohexane, the substituents are arranged as a combination of axial and equatorial in both chair conformations. However, for the "b," "c," and "d," cyclohexanes one chair has only equatorial substituents, and the other chair has only axial substituents. Why is the "a" chair conformation different? https://www.bartleby.com/solution-answer/chapter-2-problem-251p-organic-chemistry-8th-edition/9781305580350/draw-alternative-chair-conformations-for-each-substituted-cyclohexane-and-state-which-chair-is-more/4532cd91-c341-11e9-8385-02ee952b546earrow_forward
- Organic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage Learning