Organic Reactions

- Hydrocarbons -

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Flow Chart of Organic Reactions

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Single covalent bonds between carbon atoms are relatively difficult to break, and thus alkanes are rather unreactive

TWO Common Reactions of Alkanes

1) Combustion

2) Substitution

Reactions of Alkanes

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∆hydrocarbon + oxygen carbon dioxide and water

1) Combustion Reactions

C3H8(g)5O2(g) 4H2O(g)

3CO2(g)+ +

NOTE: Assume COMPLETE combustion unless otherwise stated

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Flow Chart of Organic Reactions

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C-C bonds are difficult to break, H atom may be “substituted” by a halogen atom using F2, Cl2, and Br2

Reactions with F2 are fast, Cl2 and Br2 require heat or UV to dissociate the halogen molecule first

Products halogenated alkanes called alkyl halides

2) Substitution Reaction

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Substitution reaction between ethane & bromine

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As reactions proceeds, bromoethane concentration increases resulting in more substitution reactions

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Due to double or triple bonds alkenes and alkynes are more reactive than alkanes

Traditionally alkenes and alkynes undergo ADDITION reactions – where atoms are added to the molecule without losing hydrogen atoms

Reactions of Alkenes & Alkynes

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Four Common Addition Reactions

1) Halogenation (with Br2 and Cl2)

2) Hydrogenation (with H2)

3) Hydrohalogenation (with hydrogen halides)

4) Hyration (with H2O)

Reactions of Alkenes & Alkynes

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Flow Chart of Organic Reactions

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Flow Chart of Organic Reactions

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Flow Chart of Organic Reactions

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Markovnikov’s Rule

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When a hydrogen halide or water is added to an alkene or alkyne, the hydrogen atom bonds to the carbon atom within the double bond that already has more hydrogen atoms.

“the rich get richer”

Markovnikov’s Rule

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Learning Checkpoint

Assigned Questions:

p. 27 Practice UC # 1, 2, 3

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Generally, do NOT undergo addition reactions

Less reactive than alkenes

Aromatic hydrocarbons undergo substitution reactions (easier than alkanes)

Reactivity of aromatic hydrocarbons between alkanes and alkenes

Reactions of Aromatic Hydrocarbons

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Learning Checkpoint

Assigned Questions:

p. 30 Practice UC # 4, 5, 6p. 31 Section 1.3 UC # 2, 3, 4

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