Hydrogen Atom Abstraction from a Bonded Carbon Ligands

This method is often utilized for preparation of carbene compounds which do not contain heteroatoms. Trityl salts and Me3P = CH2 are utilized as hydrogen atom trapping agents  

one of the ligands may react with a hydrogen atom of another ligand leading to the formation of a carbene compound and evolution of a hydrocarbon. 

In the case of [Ta(2, 4, 6-C6H2Me3)(Me) X3(PMe3)2] (X = Br, Cl) y-elimination of hydrogen from the methylene group of mesitylene takes place to give a carbene complex and methane  

In some syntheses, the addition of a nucleophile to a carbene atom is first carried out followed by elimination of another group to regenerate carbene complex  

Many complexes with M —C bonds react with alkylating agents to give ionic carbene compounds  

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