(a)
Interpretation: The kind of sigmatropic rearrangement that occurs in each of the given reactions has to be given.
Concept introduction:
Pericyclic reactions are “ any concerted reaction in which bonds are formed or brocken in a cyclic transition state”. There is a single transition state from start to finish, in contrast to a stepwise reaction.
There are mainly three types of pericyclic reactions,
- 1) Electrocyclic reactions
- 2) Cycloaddition reactions
- 3) Sigmatropic reactions
In a sigmatropic reaction “ one new sigma-bond is formed as another breaks.”
Sigmatropic rearrangement reactions are named with digits. For example a [1, 3] sigmatropic rearrangement describe a reaction in which the residue migrates from position 1 to position 3.
(b)
Interpretation: Using arrows the electron rearrangement takes place in the given reactions has to be shown.
Concept introduction:
Pericyclic reactions are “ any concerted reaction in which bonds are formed or brocken in a cyclic transition state”. There is a single transition state from start to finish, in contrast to a stepwise reaction.
There are mainly three types of pericyclic reactions,
- 1) Electrocyclic reactions
- 2) Cycloaddition reactions
- 3) Sigmatropic reactions
In a sigmatropic reaction “ one new sigma-bond is formed as another breaks.”
Sigmatropic rearrangement reactions are named with digits. For example a [1, 3] sigmatropic rearrangement describe a reaction in which the residue migrates from position 1 to position 3.
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Organic Chemistry
- 2. Consider the following reaction. MeOH CI b. Predict the stereochemistry of the final product(s). OMe a. Provide a reasonable arrow-pushing mechanism for the following reaction, showing all steps and balancing all charges. c. Label the electrophilic sites on the molecule and explain why only one of undergoes substitution.arrow_forward1.a. Give the product(s) of the reaction below. …...... D H₂, Pd/C Show stereochemistry. Give product(s) for this reaction. No mechanism is necessary. 1.b. Are there multiple products in 1.a.? Are there major and minor product(s)? Explain.arrow_forwardGive the all possible resonance structures of the carbocation for both the o- and m- product and explain why the m-product is formedarrow_forward
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- 2. A benzene ring alters the reactivity of a neighboring group in the so-called "benzylic" position, similarly to how a double bond alters the reactivity of groups in the "allylic" position. R .R allylic position benzylic position Benzylic cations, anions, and radicals are all more stable than simple alkyl intermediates. a) Use resonance structures to show the delocalization of the positive charge, negative charge, and unpaired electron of the benzyl cation, anion, and radical.arrow_forwarda. What is the major monobromination product of the following reaction? Disregard stereoisomers. b. What is the anticipated percent yield of the major product (as a percentage of all the monobrominated products)?arrow_forwardDraw the products of the reaction shown below. Use wedge and dash bonds to indicate stereochemistry. Ignore inorganic byproducts. 1. Os04 2. NaHSO3, H3O Select to Draw Select to Drawarrow_forward
- Organic Chemistry: A Guided InquiryChemistryISBN:9780618974122Author:Andrei StraumanisPublisher:Cengage Learning