(a)
Interpretation:
A mechanism should be proposed for the given reaction.
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.
In an electrocyclic reaction “one new sigma- bond is formed or brocken.”
Diels-alder reaction is a cycloaddition reaction which is occurs between a conjugated diene and substituted
Mechanism gives the step wise processes occurs in a particular reaction.
(b)
Interpretation:
The product should be determined for the given reaction if trans-2-butene were used instead of ethene.
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.
In an electrocyclic reaction “one new sigma- bond is formed or brocken.”
Diels-alder reaction is a cycloaddition reaction which is occurs between a conjugated diene and substituted alkene to form cyclohexene ring system. This concerted reaction can be accelerated by heating or using some catalysts.
Mechanism gives the step wise processes occurs in a particular reaction.
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Organic Chemistry
- 1. In a Birch reaction, an aromatic compound can be treated with Na/CH3OH, it can also be treated with Li/NH3 and have the same product form. One of the intermediates in the Birch reaction is a radical anion. In the example below, anisole could possibly form a radical anion A or B, then will go into C and D. Li/NH3 A B C D A. With the knowledge you have gained from what we have discussed, which anion A or B is more stable? What is your reasoning? B. Is a Birch reaction and oxidation or reduction? Why?arrow_forwardThe diene shown below will NOT react in a Diels-Alder reaction. Why not? Select one: A. The compound is not a conjugated diene. B. The compound is lacking in electron withdrawing groups. O C. This compound cannot adopt the s-cis conformation. D. The compound is lacking in electron donating groups.arrow_forwardWhich is the MAJOR product of the following reaction? Et 1) BH3:THF 2) H2O2, NaOH Which of the following best describes a key step in the mechanism for the reaction below? HO ... CH3 -CH3 dihydroxylation + en H3C- H3C- HO. electrophilic addition reaction to form a carbocation intermediate B nucleophilic attack by an alkene to form a cyclic (epoxide) intermediate elimination reaction by abstraction of a beta-hydrogen D free-radical substitution at the carbonyl carbon Which alkene will produce the HIGHEST yield of the alkyl halide below? Br. alkene HBr |arrow_forward
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- Organic Chemistry: A Guided InquiryChemistryISBN:9780618974122Author:Andrei StraumanisPublisher:Cengage Learning