PLA Week 5 More Alkene reactions PDF

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Peer Learning Association Week 5 Addition Reactions of Alkenes Learn the Reactions! Reagents

Reactions to Know

H-A Addition

HBr HCl HI

Key Rearrangement Intermediate Mark.

H3O+/H2O MeOH2+/MeOH

H2/Pt/C

Reduction of Alkenes

Alkene Isomerization

H2SO4 conc/Heat

Br2 Addition

Br2/CH2Cl2

Br2 Addition With H2O

Br2/H2O

1.) Hg(OAc) , H2O

2 Oxymercuration-Reduction 2. NaBH , -OH

Yes

No

Mark.

Both

N/A

Syn

Yes

Zaitsev

No

N/A

No

Anti/Syn

Mark

No

Mark

No

Anti-Mark

N/A

Anti

Anti

Anti

4

Hydroboration Oxidation

Ozonolysis

1.) BH3 /THF 2.) H2O2/ -OH

1.)O 3, -78 C, CH 2Cl2 2.) Me2S OR H2O2/H2O

HBr Addition with Peroxides

HBr/H2O2

No

N/A

No

Anti-Mark

Syn

N/A

Both

Br2 Addition

Br2

Br

CH2H2

Br

Br2 Br

CH2Cl2

Br H H

Show an electron pushing mechanism for the reaction. Remember all lone pairs and formal charges.

Br2 H2O

OH Br H

H

**They are given the product

Oxymercuration Reduction H

1. Hg(OAc)2, H2O 2. NaBH4, OH

HO

Show an electron pushing mechanism for the reaction. Remember all lone pairs and formal charges. OH

1. Hg(OAc)2, H2O 2. NaBH4, OH

Ozonolysis O

1. O3, -78 CH 2Cl2 2. Me2S

H O O

1. O3, -78 CH 2Cl2 2. Me2S

O

+ H

Ozonolysis Mechanism Show an electron pushing mechanism for the reaction. Remember all lone pairs and formal charges. O

1. O3, -78 CH 2Cl2 2. H2O, H2O2

HO

O

+ HO

Hydroboration

1. BH3 /THF OH

2. H2O2, H2O

What is the main difference between Hydroboration and Oxymercuration Reduction? Explain. Hydroboration and Oxymercuration both synthesize alcohols, however Hydroboration yields a anti Markovikov product and Oxymercuration yields a markovnikov product. Hydroboration is also a syn addition and Oxymercuruation is a anti addition.

What are 3 ways to synthesize an alchohol and what are the pros and cons of each. Hydroboration - Syn Addition, no carbocation rearrangement, anti mark Oxymercuration Reduction - Mark, anti addition, no carbocation rearrangement Electrophilic Addition (H3O+, H2O)- Mark, attack from both sides of the carbocation, carbocation rearrangement

HBr with Peroxides HBr

Br

EtOOEt H

HBr

Br

EtOOEt

For the first reaction, show a electron pushing mechanism. Remember all lone pairs and formal charges....