trans-Cyclooctene has been resolved, and its enantiomers are stable at room temperature. trans-Cyclononene has also been resolved, but it racemizes with a half-life of 4 min at 0°C. How can racemization of this cycloalkene take place without breaking any bonds? Why does trans-cyclononene racemize under these conditions but trans-cyclooctene does not? You will find it especially helpful to examine the molecular models of these cycloalkenes.

trans-Cyclooctene has been resolved, and its enantiomers are stable at room temperature. trans-Cyclononene has also been resolved, but it racemizes with a half-life of 4 min at 0°C. How can racemization of this cycloalkene take place without breaking any bonds? Why does trans-cyclononene racemize under these conditions but trans-cyclooctene does not? You will find it especially helpful to examine the molecular models of these cycloalkenes.

Organic Chemistry

8th Edition

ISBN:9781305580350

Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Publisher:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Chapter5: Alkenes: Bonding, Nomenclature, And Properties

Section: Chapter Questions

Problem 5.36P

See similar textbooks

Similar questions

From trans-1-chloro-2-isopropylcyclohexane, only 3-isopropylcyclohexene, the less substituted alkene, is formed. Using conformational analysis, explain why this product is observed. Also, will the E2 reaction with trans-1-chloro- 2-isopropylcyclohexane or cis-1-chloro-2-isopropylcyclohexane occur faster under the same basic conditions? CH;O Na* CH3OH CI trans-1-Chloro-2 (R)-3-Isopropylcyclohexene isopropylcyclohexane
Which of the following statements about cycloaddition reactions is not true? Cycloaddition reactions form a cyclic product with two new  bonds. The course of the reaction is determined by the symmetry of the molecular orbitals of the products. Cycloaddition reactions are concerted. Cycloaddition reactions are stereospecific.
2-vinylmethylenecyclopropane rearranges in the gas phase to 3- methylenecyclopentene. Two possible mechanisms are: a)Sketch a reaction diagram for each process b)How might an isotopic labeling experiment distinguish between these mechanisms?
Compound A, C₂H16 reacts with 1 molar equivalent(s) of hydrogen on catalytic hydrogenation. A undergoes reaction with ozone, followed by Zn treatment, to give: O CH3 O || CH3CCH₂CCH₂CCH3 CH3 Compound A Propose a structure for A. • You do not have to consider stereochemistry. • You do not have to explicitly draw H atoms. • In cases where there is more than one answer, just draw one.
Compounds X and Y are both C5H11CI products formed in the radical chlorination of pentane. Base-promoted E2 elimination of X and Y gives, in each case, a single C5H10 alkene (ignoring double bond stereochemistry). Both X and Y react in SN2 fashion with sodium iodide in acetone; Y reacts faster than X. What is the structure of Y? • Do not use stereobonds in your answer. • In cases where there is more than one possible structure for each molecule, just give one for each. • Draw one structure per sketcher. Add additional sketchers using the drop-down menu in the bottom right corner. • Separate structures with + signs from the drop-down menu. ChemDoodle (Previous Next
Compound W, C8H₁7Br, and X, CgH₁7Cl, are products of the radical bromination (W), and chlorination (X), of 2,4-dimethylhexane. W and X are each chiral. W reacts readily in water to form a chiral substitution product Y, CgH17OH. Reaction of a single enantiomer of W produces a single enantiomer of Y as the only substitution product. X likewise reacts readily in water though at a slower rate than W; a chiral substitution product Z, C8H₁7OH, is again formed. Unlike w, however, reaction of a single enantiomer of X produces Z that is nearly racemic. Propose structures for W and X. 0 • Do not use stereobonds in your answer. In cases where there is more than one possible structure for each molecule, just give one for each. • Draw one structure per sketcher. Add additional sketchers using the drop-down menu in the bottom right corner. Separate structures with + signs from the drop-down menu. ● +▾ 99.8) ChemDoodleⓇ + v ChemDoodleⓇ
Consider the reaction between (1S,3S)‑1‑chloro‑3‑methylcyclopentane and methanethiol in the presence of sodium hydroxide. (a) Draw the organic product and clearly indicate stereochemistry by showing the hydrogen on the chirality centers and using wedge and dash bonds. (b) Then analyze the stereochemistry of the product. racemic chiral achiral (1R, 3S) (1R, 3R) (1S, 3S)
Optically active (R)-2-bromobutane can be converted to 2-butanol under either conditions A or conditions B. Describe the stereochemistry of the product solutions for the two different conditions.
Draw the structure of (Z)-2,3-dichloro-4-methyl-2-hexene. • Consider E/Z stereochemistry of alkenes. • You do not have to explicitly draw H atoms. opy aste ChemDoodle
Bromine adds to cis- and trans-2-butene to give different diastereomers of 2,3-dibromobutane. What does this say about the mode of addition of bromine to thisalkene?
Arrange the following in increasing order of stability:
Dehydrohalogenation of 1-chloro-1-methylcyclopropane affords two alkenes (A and B) as products. Explain why A is the major product despite the fact that it contains the less substituted double bond.