Rearrangements in Ground and Excited States

List of Contributors

Contents of Other Volumes

Essay 13 Chemical Generation of Excited States

I. Introduction

II. Thermal Generation of Excited Carbonyls: Thermal Fragmentation of Dioxetanes

III. Thermolysis of Peroxides: Chemical Generation of Molecular Oxygen

IV. Chemiluminescent Pericyclic Rearrangements

V. Applications of Chemiexcitation to Photochemical and Mechanistic Problems

VI. Rearrangements to Produce Chemiluminescent Intermediates

References

Essay 14 Cis- Trans Isomerization of Olefins

I. Theoretical Considerations

II. Thermal Cis-Trans Isomerization

III. Thermochemical Cis-Trans Isomerization

Note Added in Proof

References

Essay 15 Photochemical Rearrangements in Trienes

I. Introduction

II. Photochemical Reactions

III. Discussion and Results

References

Essay 16 The Di-ir-Methane (Zimmerman) Rearrangement

I. General Formulation of the Reaction: An Introduction

II. The Gross Reaction Mechanism

III. Reaction Multiplicity

IV. Reaction Regioselectivity

V. Role of the Second ð Bond

VI. Reaction Stereochemistry

VII. Structural Effects: Central Substitution and Conformation

VIII. Substituent Effects

IX. Barrelene-Related Examples

X. Independent Generation of Cyclopropyldicarbinyl Diradicals

XI. Additional Examples

References

Essay 17 Photochemical Rearrangements of Enones

I. General Introduction

II. Photorearrangements of Cyclohex-2-en-l-ones

III. Rearrangements of 2-Cyclopentenones and Related Compounds

IV. Miscellaneous Rearrangements of a,0-Enones

V. Photochemical Rearrangements of â,ã-Enones

References

Essay 18 Photochemical Rearrangements of Conjugated Cyclic Dienones

I. Rearrangements of Cross-Conjugated Dienones

II. Rearrangements of Linearly Conjugated Dienones

References

Essay 19 Rearrangements of the Benzene Ring

I. Introduction

II. Nonphotochemical Rearrangements of the Benzene Ring

III. Photochemical Rearrangements of the Benzene Ring

References

Essay 20 Photorearrangements Via Biradicals of Simple Carbonyl Compounds

I. Introduction

II. Cleavage Reactions

III. Hydrogen Abstraction

IV. Cycloadditions

References

Essay 21 Photochemical Rearrangements Involving Three-Membered Rings

I. Introduction

II. Three-Membered Heterocycles with One Heteroatom

III. Three-Membered Heterocycles with Two Heteroatoms

IV. Three-Membered Heterocycles with Three Heteroatoms

V. Conclusion

References

Essay 22 Photochemical Rearrangements of Five-Membered Ring Heterocycles

I. Introduction

II. Mechanistic Possibilities for Photoisomerization of Five-Membered Heterocycles

III. Five-Membered Ring Systems with One Heteroatom

IV. Five-Membered Ring Systems with Two Heteroatoms References

Essay 23 Photochemical Rearrangements of Coordination Compounds

I. Introduction

II. Photochemical Isomerizations of Coordination Compounds

III. Stereochemical Changes during Ligand Photosubstitution: Chromium(III) Complexes

References

Index