Problem
14-1
Expected ΔH°hydrog for allene is −252 kJ/mol. Allene is less stable than a nonconjugated diene, which is less stable than a conjugated diene.
Problem
14-2
1-Chloro-2-pentene, 3-chloro-1-pentene, 4-chloro-2-pentene
Problem
14-3
4-Chloro-2-pentene predominates in both.
Problem
14-4
1,2 Addition: 6-bromo-1,6-dimethylcyclohexene 1,4 Addition: 3-bromo-1,2-dimethylcyclohexene
Problem
14-5
Interconversion occurs by SN1 dissociation to a common intermediate cation.
Problem
14-6
The double bond is more highly substituted.
Problem
14-8
Good dienophiles: (a), (d)
Problem
14-9
Compound (a) is s-cis. Compound (c) can rotate to s-cis.
Problem
14-13
300–600 kJ/mol; UV energy is greater than IR or NMR energy.
Problem
14-14
1.46 × 10−5 M
Problem
14-15
All except (a) have UV absorptions.