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 Chapter 25: Carbohydrates 
Ch 25 contents

Acetals and Ketals applied to sugars

aldehydes react with alcohols to give acetals
                         aldehyde                       hemi-acetal                                  acetal
ketones react with alcohols to give ketals
                          ketone                          hemi-ketal                                    ketal

Reaction type:  Nucleophilic Addition then nucleophilic substitution

Summary

a hemi-acetal
an acetal
Study Tip:
The important "piece" of an acetal or ketal is the central C which becomes the C of the carbonyl C=O
It can be recognised by looking for the C that is attached to two O atoms by single bonds
This carbon atom is the anomeric carbon or the anomeric center

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© Dr. Ian Hunt, Department of Chemistry, University of Calgary