Wurtz reaction is used to prepare:
AAlkenes from alkyl halides
BSymmetric alkanes from alkyl halides
CAlcohols from alkanes
DCarboxylic acids from alkanes
Answer & Solution
Correct answer: B. Symmetric alkanes from alkyl halides
**Wurtz reaction**: $2 R X + 2 Na \xrightarrow{\text{dry ether}} R{-}R + 2 NaX$.
Two alkyl halide molecules combine, with sodium metal as the reducing agent, to give a higher symmetric alkane with double the carbon chain.
Example: $\mathrm{CH_3 I + CH_3 I \xrightarrow{2Na} CH_3 CH_3}$ (ethane).
Limitation: doesn't work well for asymmetric alkanes — mixing two different RX gives a statistical mixture of R-R, R'-R' and R-R', hard to separate. So Wurtz is best for symmetric products.
Related questions
Nitration of toluene (methylbenzene) on the lab gives products mostly at:Benzene satisfies Hückel's rule with $4n + 2$ pi electrons for $n =$:Adding HBr to propene CH$_3$-CH=CH$_2$ in absence of peroxide gives mainly:The general formula for alkanes is:
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When propene reacts with HBr,