Page 913 - Advanced Organic Chemistry Part A - Structure and Mechanisms, 5th ed (2007) - Carey _ Sundberg
P. 913
A A 897
A S
A SECTION 10.5
S S
A
Electrocyclic Reactions
A
S S
A
S
S S A
disrotatory conrotatory
Fig. 10.24. Correlation diagrams for interconversion
of cyclobutene and 1,3-butadiene: (left) symmetry
forbidden disrotatory reaction; (right) symmetry
allowed conrotatory reaction.
Cyclobutene Conrotatory Transition State Butadience
8.09
6.51
4.97 4.97
5.03
3.86 3.86
3.78
–8.74 –8.74
–8.99
–9.16 –9.16
–9.34
–11.36
–12.60
Fig. 10.25. Correlation of orbitals of cyclobutene with the conrotatory transition state and the product,
1,3-butadiene. Energies (in eV) are from HF/6-31G(d) computations. Reproduced from J. Am. Chem. Soc.,
125, 5072 (2003), by permission of the American Chemical Society.
