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Fucoserratene and ectocarpene are sex pheromones produced by marine brown algae. What are their systematic names? (Ectocarpene is a bit difficult; make your best guess, and then check your answer in the Study Guide and Solutions Manual.)

Calculate the degree of unsaturation in each of the following formulas:

1. Cholesterol ${\mathrm{C}}_{27}{\mathrm{H}}_{46}\mathrm{O}$,
2. DDT ${\mathrm{C}}_{14}{\mathrm{H}}_9{\mathrm{Cl}}_5$,
3. Prostaglandin E₁, ${\mathrm{C}}_{20}{\mathrm{H}}_{34}{\mathrm{O}}_5$
4. Caffeine, ${\mathrm{C}}_8{\mathrm{H}}_{10}{\mathrm{N}}_4{\mathrm{O}}_2$
5. Cortisone ,${\mathrm{C}}_{21}{\mathrm{H}}_{28}{\mathrm{O}}_5$
6. Atropine,${\mathrm{C}}_{17}{\mathrm{H}}_{23}{\mathrm{NO}}_3$

The isobutyl cation spontaneously rearranges to the tert-butyl cation by a hydride shift. Is the rearrangement exergonic or endergonic? Draw what you think the transition state for the hydride shift might look like according to the Hammond postulate.

Reaction of 2,3-dimethyl-1-butene with HBr leads to an alkyl bromide,. On treatment of this alkyl bromide with KOH in methanol, elimination of HBr occurs and a hydrocarbon that is isomeric with the starting alkene is formed. What is the structure of this hydrocarbon, and how do you think it is formed from the alkyl bromide?

Calculate the degree of unsaturation in each of the following formulas:

b)DDT,${\mathrm{C}}_{14}{\mathrm{H}}_9{\mathrm{Cl}}_5$

Question: Name the following alkenes, including a cis or trans designation

Question: Name the following alkenes, including a cis or trans designation:

Which member in each of the following sets ranks higher?

$-H\mathrm{or}-{\mathrm{CH}}_3$

Question: Which member in each of the following sets ranks higher?

$-\mathrm{Cl}\mathrm{or}-{\mathrm{CH}}_{2}Cl$

Which member in each of the following sets ranks higher?

$-{\mathrm{CH}}_2{\mathrm{CH}}_2\mathrm{Br}\mathrm{or}-\mathrm{CH}={\mathrm{CH}}_2$