Problem
30-1
Ethylene: ψ1 is the HOMO and ψ2* is the LUMO in the ground state; ψ2* is the HOMO and there is no LUMO in the excited state. 1,3-Butadiene: ψ2 is the HOMO and ψ3* is the LUMO in the ground state; ψ3* is the HOMO and ψ4* is the LUMO in the excited state.
Problem
30-2
Disrotatory: cis-5,6-dimethyl-1,3-cyclohexadiene;
conrotatory: trans-5,6-dimethyl-1,3-cyclohexadiene. Disrotatory closure occurs.
conrotatory: trans-5,6-dimethyl-1,3-cyclohexadiene. Disrotatory closure occurs.
Problem
30-3
The more stable of two allowed products is formed.
Problem
30-4
trans-5,6-Dimethyl-1,3-cyclohexadiene; cis-5,6-dimethyl-1,3-cyclohexadiene
Problem
30-5
cis-3,6-Dimethylcyclohexene; trans-3,6-dimethylcyclohexene
Problem
30-6
A [6 + 4] suprafacial cycloaddition
Problem
30-7
An antarafacial [1,7] sigmatropic rearrangement
Problem
30-9
A series of [1,5] hydrogen shifts occur.
Problem
30-10
o-(1-Methylallyl)phenol
Problem
30-11
Claisen rearrangement is followed by a Cope rearrangement.