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(a)
Interpretation:
For the given reactions, the product formed should be explained whether it is meso- compound or a pair of enantiomers.
Concept introduction:
- Electrocyclic reaction is a concerted cyclization reaction of conjugated polyenes (π-system), in which one π-bond is converted into an σ-bond and remaining π-bonds shift their positions. Thereby the newly formed σ-bond connects the two ends of π-system to form a ring.
- The mechanism of the ring formation in the Electrocyclic reaction is drawn by using arrows representing the forming σ-bond and the shifting of π-bonds in the π-system of a polyene.
- The reaction conditions (thermal or photochemical) controls the product in such a way that the rotation for end lobes (ring closure) of the HOMO of conjugated (π-system) polyene.
- According to Woodward-Hoffmann rule for thermal and photochemical Electrocyclic reactions,
π-systems | Thermal | Photochemical |
4- π-electrons | Conrotatory | Disrotatory |
6- π-electrons | Disrotatory | Conrotatory |
- Meso-compound is superimposable to its mirror image.
- Enantiomers are the non-superimposable mirror images of each other.
To explain: the product formed is meso compound or a pair of enantiomers for each of the given reactions.
(b)
Interpretation:
For the given reactions, the product formed should be explained whether it is meso- compound or a pair of enantiomers.
Concept introduction:
- Electrocyclic reaction is a concerted cyclization reaction of conjugated polyenes (π-system), in which one π-bond is converted into an σ-bond and remaining π-bonds shift their positions. Thereby the newly formed σ-bond connects the two ends of π-system to form a ring.
- The mechanism of the ring formation in the Electrocyclic reaction is drawn by using arrows representing the forming σ-bond and the shifting of π-bonds in the π-system of a polyene.
- The reaction conditions (thermal or photochemical) controls the product in such a way that the rotation for end lobes (ring closure) of the HOMO of conjugated (π-system) polyene.
- According to Woodward-Hoffmann rule for thermal and photochemical Electrocyclic reactions,
π-systems | Thermal | Photochemical |
4- π-electrons | Conrotatory | Disrotatory |
6- π-electrons | Disrotatory | Conrotatory |
- Meso-compound is superimposable to its mirror image.
- Enantiomers are the non-superimposable mirror images of each other.
To explain: the product formed is meso compound or a pair of enantiomers for each of the given reactions.
(c)
Interpretation:
For the given reactions, the product formed should be explained whether it is meso- compound or a pair of enantiomers.
Concept introduction:
- Electrocyclic reaction is a concerted cyclization reaction of conjugated polyenes (π-system), in which one π-bond is converted into an σ-bond and remaining π-bonds shift their positions. Thereby the newly formed σ-bond connects the two ends of π-system to form a ring.
- The mechanism of the ring formation in the Electrocyclic reaction is drawn by using arrows representing the forming σ-bond and the shifting of π-bonds in the π-system of a polyene.
- The reaction conditions (thermal or photochemical) controls the product in such a way that the rotation for end lobes (ring closure) of the HOMO of conjugated (π-system) polyene.
- According to Woodward-Hoffmann rule for thermal and photochemical Electrocyclic reactions,
π-systems | Thermal | Photochemical |
4- π-electrons | Conrotatory | Disrotatory |
6- π-electrons | Disrotatory | Conrotatory |
- Meso-compound is superimposable to its mirror image.
- Enantiomers are the non-superimposable mirror images of each other.
To explain: the product formed is meso compound or a pair of enantiomers for each of the given reactions.
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Chapter 16 Solutions
ORGANIC CHEMISTRY-PRINT COMPANION (LL)
- Don't used hand raiting and don't used Ai solutionarrow_forward2' P17E.6 The oxidation of NO to NO 2 2 NO(g) + O2(g) → 2NO2(g), proceeds by the following mechanism: NO + NO → N₂O₂ k₁ N2O2 NO NO K = N2O2 + O2 → NO2 + NO₂ Ко Verify that application of the steady-state approximation to the intermediate N2O2 results in the rate law d[NO₂] _ 2kk₁[NO][O₂] = dt k+k₁₂[O₂]arrow_forwardPLEASE ANSWER BOTH i) and ii) !!!!arrow_forward
- ChemistryChemistryISBN:9781305957404Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCostePublisher:Cengage LearningChemistryChemistryISBN:9781259911156Author:Raymond Chang Dr., Jason Overby ProfessorPublisher:McGraw-Hill EducationPrinciples of Instrumental AnalysisChemistryISBN:9781305577213Author:Douglas A. Skoog, F. James Holler, Stanley R. CrouchPublisher:Cengage Learning
- Organic ChemistryChemistryISBN:9780078021558Author:Janice Gorzynski Smith Dr.Publisher:McGraw-Hill EducationChemistry: Principles and ReactionsChemistryISBN:9781305079373Author:William L. Masterton, Cecile N. HurleyPublisher:Cengage LearningElementary Principles of Chemical Processes, Bind...ChemistryISBN:9781118431221Author:Richard M. Felder, Ronald W. Rousseau, Lisa G. BullardPublisher:WILEY
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