We think you have liked this presentation. If you wish to download it, please recommend it to your friends in any social system. Share buttons are a little bit lower. Thank you!
Presentation is loading. Please wait.
Published byCory Carter
Modified about 1 year ago
Pericyclic Reactions Title Cycloaddition Electrocyclization
Ethylene -Molecular Orbitals 171 nm 167 kcal/mol 400 nm800 nm200 nm visibleUV IR Ethylene
1,3-Butadiene from Ethylene Ethylene/Butadiene
214 nm 133 kcal/mol 1,3-Butadiene -Molecular Orbitals 400 nm800 nm200 nm visibleUV IR Butadiene
258 nm 109 kcal/mol 1,3,5-Hexatriene -Molecular Orbitals 400 nm800 nm200 nm visibleUV IR Hexatriene
Butadiene Orbital Coeffients Frontier Molecular Orbitals FMOs Butadiene: Orbital Coefficients
Allyl Cation The Allylic System: Allyl Cation
Allyl Radical The Allylic System: Allyl Radical
Allyl Anion The Allylic System: Allyl Anion
Cycloaddition: Diels-Alder Reaction An Allowed [4+2] Cycloaddition Diels-Alder
Diels-Alder Reaction: The Effect of Electron Withdrawing Groups
Allyl Cation DA [4+2]-Cycloaddiitions
Diels-Alder Reaction: Mechanism Diels-Alder Mechanism
Diels-Alder Reaction: The Endo Effect Diels-Alder Endo Effect Secondary Effect
What About a [2+2] Cycloaddition? 2+2? light (h )
4n+2 Rule Thermally Allowed Cycloadditions 4n+2 Rule HOMOs LUMOs A S 2 S A 4 S A 6 S A 8 [4+2]=6 [6+4]=10 [8+6]=14 4n+2; n=1,2,3,4…..
4n Rule Photochemically Allowed Cycloadditions 4n Rule HOMOs LUMOs A S 2 S A 4 S A 6 S A 8 4n; n=1,2,3,4….. [2+2]=4 [4+4]=8 [6+6]=12 [8+8]=16 and [2+6]=8; [8+4]=12
Summary Summary of Cycloadditions Thermal 4n+2 Photochemical 4n
(E,Z,E)-Hexatriene-Cyclohexadiene Orbitals (E,Z,E)-1,3,5-Hexatriene-Cyclohexadiene Orbitals
Electrocyclization Summary Electrocyclizations n=1,2,3,4…thermal photochemical 4ncondis 4n+2discon
Violations “There are none!” Woodward and Hoffmann,The Conservation of Orbital Symmetry
Pericyclic Reactions (McM chapt 30) Polar react. (nucleophiles and electrophiles) Radical react. Pericyclic react. (concerted, cyclic TS # ) Electrocyclic.
Conjugated Dienes and U.V. Spectroscopy. Some Dienes.
Chapter 30 Orbitals and Organic Chemistry: Pericyclic Reaction Polar mechanism Radical mechanism Concerted process Electrocyclic reaction Cycloaddition.
Dr. Sheppard CHEM 4201 CONJUGATED SYSTEMS (CONTINUED)
Molecular Orbitals - Conservation of Orbital Symmetry in Concerted Processes.
Chapter 29 Pericyclic Reactions Organic Chemistry 4 th Edition Paula Yurkanis Bruice Irene Lee Case Western Reserve University Cleveland, OH ©2004, Prentice.
Third Year Organic Chemistry Course CHM3A2 Applied Frontier Molecular Orbitals Part 3i: Photochemical Pericyclic Reactions.
More on: Molecular Orbitals Pericyclic Reactions Electrocyclic Reactions.
The Diels-Alder Reaction Synthetic method for preparing compounds containing a cyclohexene ring.
Chapter 14 Conjugated Compounds and Ultraviolet Spectroscopy.
Chapter 15 Conjugated Systems, Orbital Symmetry, and Ultraviolet Spectroscopy Jo Blackburn Richland College, Dallas, TX Dallas County Community College.
Chapter 15 Copyright © 2010 Pearson Education, Inc. Organic Chemistry, 7 th Edition L. G. Wade, Jr. Conjugated Systems, Orbital Symmetry, and Ultraviolet.
30. Orbitals and Organic Chemistry: Pericyclic Reactions Based on McMurry’s Organic Chemistry, 6 th edition.
30. Orbitals and Organic Chemistry: Pericyclic Reactions Based on McMurry’s Organic Chemistry, 6 th edition ©2003 Ronald Kluger Department of Chemistry.
第四课 周环反应 1 、基础知识 A pericyclic reaction is a reaction in which bonds are formed or broken at the termini of one or more conjugated systems. The electrons.
Third Year Organic Chemistry Course CHM3A2 Frontier Molecular Orbitals and Pericyclic Reactions Part 4: Advanced Cycloaddition Reactions Facial Selectivities.
Chem 125 Lecture 67 4/13/08 Projected material This material is for the exclusive use of Chem 125 students at Yale and may not be copied or distributed.
220 Chapter 10: Conjugation in Alkadienes and Allylic Systems Conjugation: a series of overlapping p-orbitals 10.1: The Allyl Group - allylic position.
Outline for Today Review MO construction for Conjugated Systems Discuss Diels-Alder Reaction Chapter 14 – Aromaticity Tie in Aromaticity to Diels-Alder.
14. Conjugated Dienes and Ultraviolet Spectroscopy Based on McMurry’s Organic Chemistry, 6 th edition ©2003 Ronald Kluger Department of Chemistry University.
John E. McMurry Paul D. Adams University of Arkansas Chapter 14 Conjugated Compounds and Ultraviolet Spectroscopy.
Chem 125 Lecture 68 4/15/08 Projected material This material is for the exclusive use of Chem 125 students at Yale and may not be copied or distributed.
Chapter 14 Skeletal-Rearrangement Reactions Carbon-Carbon Rearrangements Carbon-Nitrogen Rearrangements Carbon-Oxygen Rearrangements Synthetic Applications.
"You cannot reason a person out of a position he did not reason himself into in the first place." Jonathan Swift.
Frontier Molecular Orbitals and Pericyclic Reactions Third Year Organic Chemistry Course CHM3A2 - Prof Jon A Preece - School of Chemistry University of.
Substantially Conductive Polymers Part 03. SYNTHESIS.
Chemistry 125: Lecture 55 February 24, 2010 (4n+2) Aromaticity Cycloaddition Electrocyclic Reactions This For copyright notice see final page of this file.
Organic Chemistry 4 th Edition Paula Yurkanis Bruice Chapter 7 Electron Delocalization and Resonance More about Molecular Orbital Theory Irene Lee Case.
© 2011 Pearson Education, Inc. 1 Organic Chemistry 6 th Edition Paula Yurkanis Bruice Chapter 7 Delocalized Electrons and Their Effect on Stability, Reactivity,
Second Year Organic Chemistry Course CHM3A2 Frontier Molecular Orbitals and Pericyclic Reactions Part 2(i): Electrocyclic Reactions An electrocyclic reaction.
10.12 The Diels-Alder Reaction Synthetic method for preparing compounds containing a cyclohexene ring.
1 Chapter 7 Ring closure (and ring opening) 7.1Intramolecular cyclization by electrophile- nucleophile 7.2Cycloadditon 7.3Electrocyclic ring closure 7.4Ring.
What is the structure of benzene? (C 6 H 6 ) first ideas:
Conjugated Dienes and Ultraviolet Spectroscopy. 2 Key Words Conjugated Diene Resonance Structures Dienophiles Concerted Reaction Pericyclic Reaction Cycloaddition.
Guillaume Barbe (1979- ) Université de Montréal November 11 th 2008 From Newton to Woodward Complete Construction of the Diels-Alder Correlation Diagram.
1 = recall alkene stability = resonance stability.
14. Conjugated Compounds and Ultraviolet Spectroscopy Based on McMurry’s Organic Chemistry, 7 th edition.
Third Year Organic Chemistry Course CHM3A2 Frontier Molecular Orbitals and Pericyclic Reactions Part 2(ii): Cycloaddition Reactions Cycloaddition reactions.
CHEMISTRY 2600 Topic #4: Addition Reactions of Conjugated Dienes Spring 2008 Dr. Susan Lait.
CHE2201, Chapter 14 Learn, 1 Conjugated Compounds and Ultraviolet Spectroscopy Chapter 14 Suggested Problems ,26-35.
1 Pericyclic reactions Electrocyclisation Sigmatropic Cycloadditions Cheletropic reactions… Frontier orbitals Correlation diagrams (MOs, States) Aromaticity.
© copyright 2011 William A. Goddard III, all rights reservedCh120a-Goddard-L14 Ch120a- Goddard- L01 1 Nature of the Chemical Bond with applications to.
Electrocyclic Reactions 14-9 Electrocyclic reactions involve the ring closure (or opening) of a single conjugated di-, tri- or polyene. These reactions.
© 2016 Cengage Learning. All Rights Reserved. John E. McMurry Chapter 14 Conjugated Compounds and Ultraviolet Spectroscopy.
Chapter 13: Conjugated -Systems Allylic Substitution—Allyl Radicals (Section 13.2) Allyl Radical Stability (Section 13.3) Allyl Cation/Anion (Section.
Chapter 7 Electron Delocalization and Resonance More about Molecular Orbital Theory Adapted from Irene Lee Case Western Reserve University.
24-1 Diels-Alder Reaction Diels-Alder reaction: Diels-Alder reaction: A cycloaddition reaction of a conjugated diene and certain types of double and.
Chemistry 125: Lecture 56 February 25, 2011 Generalized Aromaticity Cycloaddition – Diels-Alder Electrocyclic Stereochemistry Dewar Benzene This For copyright.
© 2017 SlidePlayer.com Inc. All rights reserved.