Classify the given sigmatropic rearrangement reaction.

When the given compounds undergo thermal [1,3] sigmatropic rearrangement, one forms one product, and the other forms two products. Determine the products of the reactions.

Provide a plausible mechanism for the following reaction.

Rationalize why conjugated compounds, such as the one formed in a ninhydrin reaction, are light-colored.

Determine the isoprene units of the given terpenes.

For the molecular orbitals (MOs) of 1,3,5-hexatriene, determine the MOs that are symmetrical and antisymmetrical.

For the molecular orbitals (MOs) of 1,3,5-hexatriene, determine which MO, in the excited state, is the HOMO and is the LUMO.

For the molecular orbitals of 1,3,5-hexatriene, determine how the HOMO and LUMO and the symmetric and antisymmetric orbitals are related.

Determine the number of linear dienes consistent with the formula C₇H₁₂. Do not include stereoisomers. How many of these are conjugated dienes?

Which of the reactions is anticipated to occur more quickly? Explain.

Write the significant resonance structures for the chemical species shown below.

Identify which double bond of myrcene is more reactive towards the electrophilic addition of HBr.

No matter whether the reaction is done under kinetic (0°C) or thermodynamic (100°C) control, the following diene produces the same product. Draw a plausible product and explain your observation.

A chemist wanted to investigate whether the faster formation of the 1,2-addition product in the reaction of 1,3-butadiene with HBr was due to the greater proximity of the nucleophile to the C-2 carbon in the transition state. Should he investigate the reaction using 1-methylcyclopenta-1,3-diene or 2-methylcyclopenta-1,3-diene?

The reaction of 1 mol of 4-methylpenta-1,3-diene with 1 mol of HBr produces a mixture of the following three products: 4-bromo-2-methylpent-2-ene, (E)-4-bromo-4-methylpent-2-ene, and (Z)-4-bromo-4-methylpent-2-ene. Write a mechanism that accounts for the formation of these products.