Question

What are the `"Wurtz"` and `"Kolbe"` reactions?

Answer 1

The `"Wurtz reaction"` is simply radical coupling; the `"Kolbe reaction"` is simply carboxylation of phenoxide.............

Explanation:

As far as I know (and I am happy to be corrected), neither reaction is particularly useful in the laboratory:

`"Wurtz reaction:"`

`2R-X + 2Na rarr [2R* + 2NaX] rarr R-R +2NaX`

Clearly, the reaction is thermodynamically downhill, but rather unselective.

`"Kolbe Reaction:"`

`C_6H_5OH + 2NaOH stackrel("CO"_2"/"Delta)rarr 1,2-C_6H_4CO_2^(-)Na^(+)(OH)`

This uses very high carbon dioxide pressures, and the eventual products, substituted hydroxy benzoic acids are used in aspirin synthesis.