The Barbier reaction involves nucleophilic addition of a carbanion equivalent to a carbonyl. The conversion is similar to the Grignard reaction. The
organozinc reagent is generated via an oxidative addition into the alkyl halide. The reaction produces a primary, secondary, or tertiary alcohol via a
1,2-addition. The Barbier reaction is advantageous because it is a one-pot process: the organozinc reagent is generated in the presence of the
carbonyl substrate. Organozinc reagents are also less water sensitive, thus this reaction can be conducted in water. Similar to the Grignard
reaction, a schlenk equilibrium applies, in which the more reactive dialkylzinc can be formed.
|