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Question ❔ in organic chemistry

How many mono- and dichloro derivatives are possible for (n.pentane), Give structures and names by IUPAC system .
Original post by f0ow
How many mono- and dichloro derivatives are possible for (n.pentane), Give structures and names by IUPAC system .


Why are you asking the question? Just draw them out.
Reply 2
chloropentane.pngOne way to do this systematically,

Identify the mono-chloro-pentane isomers first. Remember that the position is labelled from the end of the molecule closest to the Cl atom.

Next identify the di-chloro-pentane isomers beginning with the isomers that have the 2 Cl atoms on the same carbon.

Finally identify the di-chloro-pentane isomers with the 2 Cl atoms on different carbons. Start with 1,X dichloropentanes, moving on to the 2,X dichloropentanes. Consider whether it is necessary to go further, if not, why not ?

The naming convention is simple, X-chloropentane for mono substituted isomers, X,Y-dichloropentane for dichloro isomers. (X and Y being the substituted position(s))

I attach the full set of molecules for you to check you answer against.

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