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 mCPBA

to form an oxygen bonded to two carbons mCPBA

Basic E2 Reaction

E2 is anti periplanar ( H and X have to be opposite from eachother)

requires a strong base (anything that involves Na works, if you see Na it is probably E2)

Take down a hydrogen and the halogen to create a double bond. take the hydrogen from the least substitued side

Opening of Epoxides

So you can open epoxides and add hydroxiles to both sides, you can do it with just water of hydroxyle, both leave it with an anti-stereochemistry.

Formation of Dibromocarbenes and Dichlorocarbenes

In order do form a diXcarbene you need to take the electrons of the double bond and connect them with the C that needs electrons that is already connected to 2 X.

KOH as a solvent, CHX3

Formation of the acetylide anion

in handy when connecting with other moecules. Basically removes an extreme H that was adjacent to a triple bond.

NaNH2

Uses of the acetylide anion with methyl or primary halides

Uses of the acetylide anion

Uses of the acetylide anion with secondary or tertiary halides

E2 reaction,

Synthesis of Alkynes

*Need either geminal or

vicinal dihalides

*Look up mechanism

*NaNH2

FAVORS

terminal

*KOH FAVORS internal

Halogenation of Alkynes - X2 and Alkyne

Stereochemistry cannot be controlled, so you get a racemic mixture. If you do the step again you will break the double bond and add other 2 Br.

Halogenation of Alkynes HX

Mark (Hs add to the side that has the most H (less sub)) , same stereochemistry

Halogenation of Alkynes, HBr and ROOR

anti mark, same stereochemistry

Catalytic reduction with reactive catalyst of a triple bond

takes it all the way back to the alkane, too reactive to yield a double bond.

Alkyne to Alkene:

TRIPLE to DOUBLE Lindlar's catalyst

quinoline, H2 / Pd(BaSO4) , syn addition

Alkyne to Alkene:

TRIPLE to DOUBLE Dissolving a metal

Na / NH3, anti addition

Addition of H-OH to alkynes - mercuric ion

*Mark addition

*If not terminal, you will

get a mixture.

*Formation of ketone

Addition of H-OH to alkynes - hydroboration

*Antimark addition

*will get a mixture if not

terminal

*Formation of aldehyde

Oxidation of alkynes (mild conditions)

*Forms vicinal

carbonyls

*further oxidizes terminal

alkynes to form

carboxylic acid.

Oxidation of alkyne (strong)

cleavages of alkynes

ozonolysis

The Grinard Reagent Mg

The organolithium reagent

Formation of alcohols

from Grignard

Grignard and esters

or acid halides

Grignard and Epoxides

(opening of epoxides)

Corey-House Reaction

Hydride reduction of carbonyls - mild conditions (NaBH4

as reagent)

Hydride reduction of carbonyls - strong conditions (LiAlH4

as reagent)

Rayney Nickel

Oxidation of Secondary Alcohols

Oxidation of primary Acohols

Formation of the

Tosylate Ester

Formation of alkyl halide

from 3ary alcohols

Formation of 1o

/2o

alkyl halides from 1o

/2o

alcohols

Unique cleavage with

HIO4

Formation of Alkoxide Anion

Williamson ether

synthesis

Ethers from intermolecular

dehydration

Pinacol - Pinacolone

Rearrangement

Fischer Estherification