Lecture 10 Substituted Cycloalkanes

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Lecture 10 - Substituted Cycloalkanes alcohols
and alkyl halides

• Chapter 3
• Disubstituted cycloalkanes
• Relative stabilities
• Bicyclic ring systems
• Heterocyclic systems
• Chapter 4
• Nomenclature, classification
• Physical properties

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Disubstituted Cycloalkanes - Relative Stabilities
Cis-1,2-dimethylcyclopropane is less stable than
the trans isomer
Cis-1,2-dimethylcyclohexane is less stable than
the trans isomer Cis-1,3-dimethylcyclohexane is
more stable than the trans isomer Cis-1,4-dimethyl
cyclohexane is less stable than the trans isomer
All based on interactions between substituents
and other groups on the ring
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Cis and trans cyclopropanes
cis
trans
Cis-1,2-dimethylcyclopropane is less stable than
the trans isomer
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1,2-Disubstituted Cyclohexanes
cis-1,2-dimethyl cyclohexane
trans-1,2-dimethyl cyclohexane
Cis-1,2-dimethylcyclohexane is less stable than
the trans isomer
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1,3-Disubstituted Cyclohexanes
cis-1,3-dimethyl cyclohexane
trans-1,3-dimethyl cyclohexane
Cis-1,3-dimethylcyclohexane is more stable than
the trans isomer
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1,4-Disubstituted Cyclohexanes
cis-1,4-dimethyl cyclohexane
trans-1,3-dimethyl cyclohexane
cis-1,3-dimethylcyclohexane is less stable than
the trans isomer
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Bicyclic Systems
Bicyclobutane
Bicyclo3.2.0heptane Bicyclo2.2.2octane
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Heterocyclic Rings
tetrahydrofuran pyyrolidine
piperidine
Later...
nicotine
2-deoxyribose
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Chapter 4 - Alcohols and Alkyl Halides

• Nomenclature - Alkyl Halides
• Functional class nomenclature

pentyl chloride
1-methylethyl iodide
cyclohexyl bromide

• Substitutive nomenclature

2-chloro-5-methylheptane
2-bromopentane
3-iodopropane
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Alcohol Nomenclature
pentanol
cyclohexanol
propan-2-ol
pentan-2-ol
5-methyl- heptan-2-ol
1-methyl cyclohexanol