Question
What is meant by the Ketal? Give an example.
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Answer
Gem-Dialkoxyalkanes in which the two alkoxy groups are present on the same carbon within the chain are called ketals. These are produced when a ketone is heated with ethylene glycol in presence of dry HCl gas or p-toluenesulphonic acid (PTS).
These are easily hydrolysed by dilute mineral acids to regenerate the original ketones. Therefore, ketals are used for protection of keto groups in organic synthesis.
These are easily hydrolysed by dilute mineral acids to regenerate the original ketones. Therefore, ketals are used for protection of keto groups in organic synthesis.
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