The compounds which contain bond between carbon atom and the atoms which are more electropositive than carbon are known as Organometallic compounds. An Organometallic compound contains atleast one direct metal-carbon (M-C) bond, but it is not a rigid condition. The carbon containing groups may be carbonyl, alkyl, alkene, alkyne, aryl, allyl, cyclic, or heterocyclic. This topic is essential for CSIR NET coaching in chemistry . It is also beneficial topic for IIT JAM coaching in Chenistry. Eg:- (i) Organo-magnecium compounds RMgX (Grignard Reagent) (ii) Organo-copper compounds R2CuLi (Gilmann Reagent) (iii) Organo –lithium compounds RLi (R = -Ph, -Bu…..) Some Important Exceptional Cases:- Eg:-(1) Metal carbides and cyanides are not Organometallic compounds i.e. CaC2, NaCN. Eg:-(2) Wilkinson catalyst :-It does not contain any M-C bond, even though it is a very important Organometallic compound and used for hydrogenation of alkenes and alkynes.