Organic Chemistry 1: All Reaction Mechanisms

All mechanisms, starting from chapter 7

Addition of HX

Follows Mark

Mechanism:

1. protonation of the double bond

2. add Br to the carbocation

Addition of HBr on ROOR

Anti-Mark

same mechanism as addition of HX, except Br adds to the least substituted

Halide Addition X2

Solvent can be CH2Cl2 or CCl4 (NO WATER)

Anti-Stereochemistry.

Mehanism:
1. double bond breaks and has one X attach to both of the carbons in the double bond (triangle)

2. Second X attacks and it forms a bond with one of the Cs.

Halohydrin Reaction X2 + H2O

Mark

Anti-stereochemistry

Forming alkene from vicinal dihalide

(wanting to create a double bond when u have 2 halogens attached to vicinal carbons)

Need to have a NaI of KI under an acetone solvent

Dehydration to alkene With H2SO4

Only gives a middle alkene

1. add a hydrogen to the OH

2. the H2O leaves

3. give one of the electrons of one of the H to create a doube bond and take the H with the water.

Dehydrogenation of alkene with POCl3

Only gives a terminal alkene

Addition of OH

racemic mixture

mark

Oxymercuration/ demercuration (only water)

mark, antistereochemistry (see other to check mechanism (too long))

Oxymercuration / Demercuration with CH3OH

mark and anti-stereochemistry

Adds a CH3 to the Oxygen, compared to just the alcohol in the reaction with ony water.

Hydroboration

BH3 / THF

2) H2O2 / -OH

anti mark, same stereochemistry.

Mechanism:
1. BH3 adds to the double bond on a single step

2. Then gets replaced by a OH

Catalytic Hydrogenation, Pt, Pd, or Ni

same stereochemistry, adds 2 Hydrogens to where the double bond was

Hydroxylation of Alkenes by OsO4 / on H2O2

Syn formation of 2 alcohols (OH)

Hydroxylation of Alkenes by KMnO4 (cold / basic) / on H2O2

Cold - Basic reaction conditions needed

Syn formation of 2 alcohols

Hydroxylation of Alkenes by CH3CO3H / on H2O

ANTI STEREOCHEMISTRY

Epoxidation

An alkene reacts with peroxide acit to produce an epoxide

Oxidation of alkenes: Ozonolysis

Ozone breaks the double bond to produce aldehydes and ketones.

Breaks through the middle.

*Can use Zn/acetic acid instead of (CH3)2S

Oxidation of Alkenes: Warm KMnO4 Cleavage

*further oxidizes to form carboxylic acids

*cannot isolate the formaldehyde (the H2C=O)

Addition of Carbenes (R2C:)

Either uses CH2N2 + heat or uses CH2I2 + Zn(Cu)

Oxidation of Alkenes: oxirane synthesis

to form an oxygen bonded to two carbons