What is Wurtz Reaction? – Examples, Mechanism
What is Wurtz Reaction?
The Wurtz reaction is a chemical reaction used to couple two alkyl halides to form an alkane. This type of reaction is particularly useful in organic synthesis for the formation of carbon-carbon bonds. The reaction is named after Charles-Adolphe Wurtz, a French chemist who first described it in 1855.
Few Wurtz Reaction Examples for Better Understanding
Let’s look at a couple of examples to illustrate the Wurtz reaction:
- Example 1:
Reactants: 2 moles of Ethyl bromide (\(C H_{3}CH_{2}Br\))
Reaction: \(2C H_{3}CH_{2}Br + 2Na \longrightarrow C H_{3}CH_{2}C H_{3}CH_{2}+2NaBr\)
Product: Butane \(C H_{3}CH_{2}C H_{3}CH_{2}\)
- Example 2:
Reactants: Methyl iodide (\(C H_{3}l\)) + Ethyl iodide (\(C H_{3}C H_{2}l\))
Reaction: \(2C H_{3}l+2Na \longrightarrow C H_{3}C H_{3}+2Nal\)
Product: Ethane \(C H_{3}C H_{3}\)
How to Write Wurtz Reaction Equation?
Writing the Wurtz reaction equation involves several steps:
- Identify Reactants: Determine the alkyl halides (e.g., CH3X) involved in the reaction.
- Balancing the Equation: Ensure that the number of carbon atoms in the reactants equals the number of carbon atoms in the products.
- Writing the Product: Combine the alkyl groups from the reactants to form the new carbon-carbon bond.
For example, to write the Wurtz reaction equation for the synthesis of butane from ethyl bromide:
\(2CH_{3}C H_{2}Br+2Na \longrightarrow C H_{3}CH_{2}C H_{3}CH_{2}+2NaBr\)Complete Wurtz Reaction Mechanism
The mechanism of the Wurtz Reaction involves the following steps:
- Formation of Radical Species: Sodium metal generates free electrons that abstract a halogen atom (X) from the alkyl halide, creating an alkyl radical (R•).
- Formation of Sodium Alkyl: The alkyl radical then reacts with another alkyl halide, forming a new carbon-carbon bond and a sodium halide (Na-X).
- Coupling Reaction: The final step involves coupling of two alkyl radicals to produce the desired alkane product.
This mechanism underscores the importance of radical intermediates in the Wurtz Reaction.
This process can be summarized as:
\(2R-X+2Na \longrightarrow R-R+2NaX\)Limitations of Wurtz Reaction
The major limitations of wurtz reaction are given below,
- This reaction is limited to symmetrical alkyl halides.
- Cross-coupling reactions can occur, leading to unwanted side products.
- The reaction conditions can be harsh and require high temperatures.
What is Wurtz-Fittig reaction?
The Wurtz-Fittig reaction is a variation of the Wurtz reaction that involves coupling an alkyl halide with an aryl halide to form an alkyl-aryl compound. This reaction expands the versatility of the Wurtz reaction in organic synthesis.
Wurtz-Fittig reaction vs Wurtz Reaction
The major difference between the Wurtz reaction and the wurtz-fitting reaction is given below,
- The Wurtz-Fittig reaction involves one alkyl halide and one aryl halide, while the Wurtz reaction involves two alkyl halides.
- The Wurtz-Fittig reaction can lead to the formation of complex organic molecules with both alkyl and aryl groups.
- The Wurtz reaction is mainly used for simple alkane synthesis, while the Wurtz-Fittig reaction is used for more elaborate molecule construction.
Final Notes
In conclusion, the Wurtz reaction is a valuable tool in organic synthesis for forming carbon-carbon bonds. Understanding the mechanism and examples of this reaction can help in designing efficient synthetic routes in organic chemistry.
This article explores in detail the Wurtz reaction along with the Wurtz reaction mechanism. For further insights into related concepts, we encourage you to explore our blog section. If you seek personalized online tuition, Tutoroot offers exceptional services. Our online chemistry tuition can assist in clarifying any doubts you may have. Click here to book a FREE DEMO session.
FAQs
Explain Wurtz reaction.
The Wurtz reaction is a chemical reaction that involves coupling two alkyl halides to form an alkane.
What is Wurtz Reaction Equation?
The Wurtz reaction equation represents the reaction of two alkyl halides to produce an alkane along with sodium halides as byproducts.