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

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Answer 1 · 2017-03-21T05:40:18

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

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.