Draw and name all structural isomers formed by monochlorination of each alkane cyclopentane , CH3CH2CH2CH2CH3 , and (CH3)3CH?

1 Answer
Aug 26, 2015

See below.

Cyclopentane

The structure of cyclopentane is

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All the H atoms are equivalent, so you get only one monochlorination product.

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The product is chlorocyclopentane.

Pentane

Pentane has three non-equivalent hydrogen sites.

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The methyl groups at each end of the chain are clearly different from all the rest.

Substitution of one of these #"H"# atoms will give 1-chloropentane.

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The three #"CH"_2# groups split into two — the middle #"CH"_2# is different simply because it is in the middle.

Substitution of the middle #"CH"_2# with chlorine gives 3-chloropropane.

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Finally, substitution of any of the remaining four #"CH"_2# hydrogen atoms gives 2-chloropropane.

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2-Methylpropane

"We leave it as an exercise for the student" to answer this part.

Hint: there are two types of hydrogen atom.