Organolithium compounds may be made by a similar oxidative insertion reaction from lithium metal and alkyl halides. Each inserting reaction requires two atoms of lithium and generates one equivalent of lithium halide salt. As with Grignard formation, there is really very little limit on the types of organolithium that can be made this way.

You will notice secondary alkyllithium, an aryl lithium, and two vinyllithiums. The only other functional groups are alkenes and an ether. So far, that is quite like the formation of Grignard reagents. However, there are differences. Lithium goes from Li (0) to Li(I) during the reaction and there is no halide attached to the Li. Instead, a second Li atom has to be used to make the Li halide. Again, Li(I) is very much more stable than Li (0) so the reaction is irreversible. Although ether solvents are often used, there is less need for extra coordination and hydrocarbon solvents such as pentane or hexane are also good.

مواضيع ذات صلة

Organometallics as bases

Making organometallics, How to make Grignard reagents

Organometallic compounds contain a carbon–metal bond

Lewis acids and bases

pKa in action—the development of the drug cimetidine

Why do we need to compare acid strengths of O and N acids?

Carbon acids

Substituents affect the pKa

The ‘pKas’ of bases

Nitrogen compounds as acids and bases

Delocalization of the negative charge stabilizes the conjugate base

Constructing a pKa scale