It is to be explained if diene A or diene B will react faster in a standard Diels-Alder reaction. Concept introduction: [ 4+2 ] cycloaddition reactions are generally known as Diels-Alder reactions. A Diels-Alder reaction involves a diene and a dienophile. A diene shares four π electrons from the two conjugated π bonds while a dienophile shares two π electrons from a single π bond. The Diels-Alder reaction is concerted and proceeds through a six-membered aromatic transition state. For a Diels-Alder reaction to occur, the diene must be present in the s-cis conformation because both ends of the diene must be relatively close to the dienophile in the transition state. In a Diels-Alder reaction, the dienophile must be electron-poor, and the diene must be electron-rich. The electron-donating substituents bonded directly to the dienes carbons increase the rate of a Diels-Alder reaction. These are the same substituents as activating groups in electrophilic aromatic substitution. While electron-withdrawing substituents bonded directly to the dienophile carbons facilitate standard Diels-Alder reaction, these are the same substituents that act as deactivating groups in electrophilic aromatic substitution.

Question

Want to see the full answer?

Answer 1

Question

Chapter 24, Problem 24.7P

Interpretation Introduction

Interpretation:

It is to be explained if diene A or diene B will react faster in a standard Diels-Alder reaction.

Concept introduction:

[4+2] cycloaddition reactions are generally known as Diels-Alder reactions. A Diels-Alder reaction involves a diene and a dienophile. A diene shares four π electrons from the two conjugated π bonds while a dienophile shares two π electrons from a single π bond. The Diels-Alder reaction is concerted and proceeds through a six-membered aromatic transition state. For a Diels-Alder reaction to occur, the diene must be present in the s-cis conformation because both ends of the diene must be relatively close to the dienophile in the transition state. In a Diels-Alder reaction, the dienophile must be electron-poor, and the diene must be electron-rich. The electron-donating substituents bonded directly to the dienes carbons increase the rate of a Diels-Alder reaction. These are the same substituents as activating groups in electrophilic aromatic substitution. While electron-withdrawing substituents bonded directly to the dienophile carbons facilitate standard Diels-Alder reaction, these are the same substituents that act as deactivating groups in electrophilic aromatic substitution.

Expert Solution & Answer

Want to see the full answer?

Check out a sample textbook solution

See solution

Students have asked these similar questions

יווי 10 20 30 40 50 60 70 3.5 3 2.5 2 1.5 1 [ppm] 3.5 3 2.5 2 1.5 1 6 [ppm] 1 1.5 -2.5 3.5

2H2S(g)+3O2(g)→2SO2(g)+2H2O(g) A 1.2mol sample of H2S(g) is combined with excess O2(g), and the reaction goes to completion. Question Which of the following predicts the theoretical yield of SO2(g) from the reaction? Responses 1.2 g Answer A: 1.2 grams A 41 g Answer B: 41 grams B 77 g Answer C: 77 grams C 154 g Answer D: 154 grams D

Part VII. Below are the 'HNMR, 13 C-NMR, COSY 2D- NMR, and HSQC 2D-NMR (similar with HETCOR but axes are reversed) spectra of an organic compound with molecular formula C6H1003 - Assign chemical shift values to the H and c atoms of the compound. Find the structure. Show complete solutions. Predicted 1H NMR Spectrum 4.7 4.6 4.5 4.4 4.3 4.2 4.1 4.0 3.9 3.8 3.7 3.6 3.5 3.4 3.3 3.2 3.1 3.0 2.9 2.8 2.7 2.6 2.5 2.4 2.3 2.2 2.1 2.0 1.9 1.8 1.7 1.6 1.5 1.4 1.3 1.2 1.1 f1 (ppm) Predicted 13C NMR Spectrum 100 f1 (ppm) 30 220 210 200 190 180 170 160 150 140 130 120 110 90 80 70 -26 60 50 40 46 30 20 115 10 1.0 0.9 0.8 0 -10