Organolithium reagents compounds

These compounds are sources of the nucleophilic anion RC=C and their reaction with primary alkyl halides provides an effective synthesis of alkynes (Section 9 6) The nucleophilicity of acetylide anions is also evident m their reactions with aldehydes and ketones which are entirely analogous to those of Grignard and organolithium reagents... 

Organolithium reagents (Section 14 3) Lithi um metal reacts with organic halides to pro duce organolithium compounds The organic halide may be alkyl alkenyl or aryl Iodides react most and fluorides least readily bro mides are used most often Suitable solvents include hexane diethyl ether and tetrahy drofuran... 

Products are contaminated with more highly alkylated compounds, but less so than without the active metal. The phosphide can be generated from a Grignard or organolithium reagent. 

R Tl compounds, eg, methyl [3003-15-4], ethyl [687-82-1], isobutyl [3016-08-8], and phenyl [3003-04-1] thaHium(III), are usuaHy prepared by the reaction between a dialkyl or diarylthaHium haHde and an organolithium reagent in ether (16) ... 

Organolithium compounds are sometimes prepared in hydrocarbon solvents such as pentane and hexane, but nonnally diethyl ether is used. It is especially important that the solvent be anhydrous. Even trace amounts of water or alcohols react with lithium to form insoluble lithium hydroxide or lithium alkoxides that coat the surface of the metal and prevent it from reacting with the alkyl halide. Furthennore, organolithium reagents are strong bases and react rapidly with even weak proton sources to fonn hydrocarbons. We shall discuss this property of organolithium reagents in Section 14.5. 

Organolithium reagents are also valuable in the synthesis of other organometallic compounds via... 

As precursors of the organocopper compounds, organolithium reagents are slightly preferable to organomagnesium halides. 

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