5340-80-7Relevant articles and documents
Effets de cryptands et activation de bases. VI. Reactions d'organo-lithiens.
Perraud, Robert,Handel, Henri,Pierre, Jean-Louis
, p. 283 - 288 (2007/10/02)
Utilization of the cryptand shows the need of electrophilic catalysis by the Li(1+) ion in the nucleophilic addition of organolithium compounds to ketones, esters, or carboxylic acids.When nucleophilic addition is inhibited, organolithium reagents enolyze ketones or esters.When activated by cryptation of Li(1+), organolithium reagents attack ethers in a few minutes.With alkyl halides, only elimination takes place: exchange and nucleophilic substitution are not observed any longer in the presence of the cryptand.Generally speaking, the cryptand seems to enhance the basicity of the organolithium reagent, and nucleophilicity does not manifest itself any more.