Adrian Mulholland
Molecular Structure and Bonding
p Electrons in Conjugated Organic Molecules
Lecture 6
Alternative approaches for pericyclic reactions. Frontier orbitals.
Computational chemistry and molecular modelling
Summary
- Understanding pericyclic reactions: alternative models
- Frontier orbitals: HOMO and LUMO
- Charge transfer interactions. Correlation with experiments
· Molecular
modelling and computational chemistry
Alternative
models for understanding pericyclic reactions
- Correlation diagrams based on orbital symmetry properties allow us
to predict which pericyclic reactions are forbidden or allowed – i.e. to
predict the chemistry that will occur.
- These lead to the Woodward-Hoffmann Rules (see previous handout)
- Useful extra insight comes from alternative, simpler models for predicting
pericyclic reactions – these predict the same reactions to be allowed or
forbidden, but are simpler ‘rules of thumb’ that can be used easily.
Next:
alternative models for pericyclic reactions (cont.)