Organic Chemistry I: Chapter 8 PDF

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Lecture notes for Organic Chemistry II
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6/15/2017

Chapter Eight

Reaction of Alkenes

Section 8-1 Reactivity of the Carbon-Carbon Double Bond - Single bonds are more stable than pi bonds. - Double bonds will break down to sigma bonds.

Section 8-2 

Electrophilic Additions  an addition in which the electrophile bonds to one of the double-bonded carbons first, followed by the nucleophile.

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Section 8-2

Section 8-3 

Makik Rle  when a proton acid adds to the double bond of an alkene results in a product with the acid proton bonded to the carbon atom that already holds the greater number of hydrogens. 



Original

Makik Rle  for an electrophilic addition to the alkene, the electrophile adds in such a way as to generate the most stable intermediate. 

Extended

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Section 8-3

Section 8-3: Markoniko Rle

Section 8-3: Markoniko Rle

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Section 8-3 

Anti-Markovnikov Product  an orientation that is the opposite of that predicted by the original aemen of Markoniko Rle.  



Only works with HBr in the presence of peroxide. HCl and HI in the presence of peroxide will still give the Markovnikov product, since the reaction is endothermic.

Peroxide Effect  the reversal of orientation of HBr addition to alkenes in the presence of peroxide.

Section 8-3

Section 8-3: Anti-Markovnikov Product

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Section 8-4 Addition of Water - Dilute the acid to force the equilibrium to the alcohol. - Markovnikov product

Section 8-4

Section 8-4: Addition of Water

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Section 8-5 Hydration by Oxymercuration-Demercuration - Water is the solvent - No carbocation - No rearrangement

Section 8-5 Oxymercuration-Demercuration

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Section 8-6 Alkoxymercuration-Demercuration - Alcohol is the solvent - No carbocation - No rearrangement

Section 8-6 Alkoxymercuration-Demercuration

Section 8-7 

Hydroboration  the addition of borane or one of its derivatives to a molecule. 

BH3 is a strong electrophile and is electron deficient.

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Section 8-7 Hydroboration-Oxidation - Stereospecific Reaction - Same side of the double bond (syn addition)

Section 8-7

Section 8-7: Hydroboration-Oxidation

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Section 8-7: Hydroboration-Oxidation

Section 8-8 Addition of Halogens to Alkenes - Inert solvents like CCl4, CHCl3, CH2Cl2

Section 8-8

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Section 8-8 Stereochemistry of Halogen Additions

Section 8-9 

Halohydrin  an alcohol with a halogen on the adjacent carbon.   

Must have a good nucleophile presence like water. The addition forms an anti product. Markovnikov product.

Section 8-9

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Section 8-10 Catalytic Hydrogenation of Alkenes - Syn addition

Section 8-10 Catalytic Hydrogenation of Alkenes

Section 8-10 

Enantioselective Synthesis  the formation of an optically active product from an optically inactive starting material. Such a process requires the use of an optically active reagent or catalyst. 

2001 Noble Prize

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Section 8-11 Addition of Carbenes to Alkenes - Use diazomethane CH2N2 to produce methylene. - Very reactive and is explosive. - Many side reactions are possible.

Section 8-11 Simmons-Smith Reaction

Section 8-11 Simmons-Smith Reaction

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Section 8-11 Formation of Carbenes by Alpha Elimination

Section 8-11 Formation of Carbenes by Alpha Elimination

Section 8-12 Epoxidation of Alkenes

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Section 8-12 Epoxidation of Alkenes

Section 8-13 Acid-Catalyzed Opening of Epoxides - Acid catalyzed reaction. - Water attacks the protonated epoxide on the opposite side of the ring. - Antidiol is formed.

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Section 8-14 

Hydroxylation  the addition of two hydroxyl groups, one at each carbon of the double bond.

Syn Hydroxlation of Alkenes

Section 8-14 Osmium Tetroxide Dihydroxylation

Section 8-14 Permanganate Dihydroxylation

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Section 8-15 Oxidative Cleavage of Alkenes

Section 8-15 Ozonolysis

Section 8-16 

Addition Polymerization  a polymer that results from rapid addition of one molecule at a time to a growing polymer chain, usually with a reactive intermediate at the growing end of the chain.   

Cationic Polymerization Free-Radical Polymerization Anionic Polymerization

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Section 8-16 Cationic Polymerization

Section 8-16 Free-Radical Polymerization

Section 8-16 Anionic Polymerization

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Section 8-17 

Olefin Metathesis  any reaction that trades and interchanges alkylidene groups around a double bond.

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