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d) Will all three alkenes undergo Markovnikov addition of HBr? If not, which alkene or alkenes

wont and why?

In both A and B, the carbocation leading to Markovnikov product is more stable than that

leading to the anti-Markovnikov product. However, in C, the positive charge is even more

localized by induction, making it the less stable carbocation. The stability favors the carbocation

on the other carbon, leading to the correct product.

A B C

CH3 O CH3 C F

F F

!-

!-!-

O CH3

! +

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2. Provide a mechanism for the following reaction. Then, predict the reaction energy diagram for the

entire reaction in the space provided. In your diagram, you must indicate the H of the reaction,

label the activation energy (Ea) of the rate-determining step, and clearly identify all intermediates

and products of the reaction.

Br

H Br

Br

HH

HH

+

A

BC

D

A

H Br

B

Br

C

Br

D

!H

Ea

Energy

Rxn Coordinate

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3. What starting materials & reagents are needed to produce the following compound?

Br2

Br Br

4. Draw the major product of each of the following reactions. Be sure to include stereochemistry in

your answers where appropriate.

CH3

CH3

CH3

CH3 Br2

H Cl

Cl2

CH3CH2OH

CH3

OH

CH3

CH3Cl

H

CH3

CH3

Cl

H

CH3

H

OH

CH3CH2OCl

CH3 Br

Br

CH3

H

OH

CH3

CH3Cl

H

CH3

CH3Cl

H

CH3 Br

Br

CH3CH2OCl

d)

a)

b)

c)1) Hg(OAc)2 / H2O

2) NaBH4

1) BH3THF

2) H2O2 , NaOH