Ethanol is cheap. Sulfuric acid is cheap. Over 10 million tons of the stuff annually via this process. Secondly, the temperature has to be carefully optimized, because there are lots of side reactions possible. For example the optimal temperature for the formation of diethyl ether is about degrees C.
Once the temperature gets to degrees and above, elimination starts to compete, leading to the formation of ethylene gas. Once you get into the category of using this process for secondary and tertiary alcohols, carbocations are much easier to form and elimination becomes an even more significant destructive pathway. You should know what the correct answer for this question is.
And be able to draw the mechanism. The alkylating agent, on the other hand is most preferably primary. Secondary alkylating agents also react, but tertiary ones are usually too prone to side reactions to be of practical use. The leaving group is most often a halide or a sulfonate ester synthesized for the purpose of the reaction.
Since the conditions of the reaction are rather forcing, protecting groups are often used to pacify other parts of the reacting molecules e. Conditions[ edit ] Since alkoxide ions are highly reactive, they are usually prepared immediately prior to the reaction, or are generated in situ.
In laboratory chemistry, in situ generation is most often accomplished by the use of a carbonate base or potassium hydroxide , while in industrial syntheses phase transfer catalysis is very common. A wide range of solvents can be used, but protic solvents and apolar solvents tend to slow the reaction rate strongly, as a result of lowering the availability of the free nucleophile.
For this reason, acetonitrile and N,N-dimethylformamide are particularly commonly used. Often the complete disappearance of the starting material is difficult to achieve, and side reactions are common. Catalysis is not usually necessary in laboratory syntheses. However, if an unreactive alkylating agent is used e.
Next, another equivalent of the alcohol can now perform nucleophilic attack at carbon SN2 , leading to displacement of OH2 water and formation of a new C-O bond. Pays-Bas , , E [4- Pentenyloxy phenyl]acrylicc Acid. Sulfuric acid is cheap. Kollonitsch, J.
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