Organolithiums

Organolithiums

• Organolithiums are those organometallic compounds which consists of carbon lithium bond.

• General Formula R-Li or Ar-Li

• Organolithiums have more ionic character than Grignard reagent due to small size and high polarity.

• They are mostly liquids

• Readily soluble in organic solvents

• Examples: Methyllithium, Phenyllithium, Ethyllithium,etc.
  

  Nomenclature and Examples

  Alkyl Group + lithium=alkyllithium

  Methyl+lithium=Methyllithium

  Ethyl+lithium=Ethyllithium

  
  

  Aryl Group + lithium=aryllithium

  Phenyl+lithium=Phenyllithium

  
  

  Preparation of Organolithiums

  From haloalkanes:

  Organolithiums can be directly prepared by combining haloalkanes with Lithium

       

                                                                     

  

  
  

  
  

  USES OF ORGANOLITHIUMS

  • Organolithiums are mostly used in making lithium diorganocopper compounds by reacting Copper(I) Iodide or Copper(II) Iodide in ether solvents. 
    
                                                                                               
    
    
  • Also, organolithiums are used as nucleophiles to initiate polymerization reaction.
  • They are also used as bases and superbases.
  • Organolithium compounds are also commonly used for nucleophilic addition reactions to carbonyl compounds and other carbon electrophiles with deprotonation as side reaction.