#Dehydration_alcohols
#organic_chemistry_lab

One way to synthesize alkenes is by dehydration of alcohols, a process in which alcohols undergo E1 or E2 mechanisms to lose water and form a double bond. The dehydration reaction of alcohols to generate alkene proceeds by heating the alcohols in the presence of a strong acid, such as sulfuric or phosphoric acid, at high temperatures.

general rxn complete.png

The required range of reaction temperature decreases with increasing substitution of the hydroxy-containing carbon:

1° alcohols: 170° - 180°C
2° alcohols: 100°– 140 °C
3° alcohols: 25°– 80°C
If the reaction is not sufficiently heated, the alcohols do not dehydrate to form alkenes, but react with one another to form ethers

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